Merge branch 'maint'

16 files changed, 1037 insertions, 431 deletions

diff --git a/lib/diameter/src/.gitignore b/lib/diameter/src/.gitignore
index feeb378fd8..cc06720fd1 100644
--- a/lib/diameter/src/.gitignore
+++ b/lib/diameter/src/.gitignore
@@ -1,2 +1,3 @@
 
 /depend.mk
+/otp.plt
diff --git a/lib/diameter/src/Makefile b/lib/diameter/src/Makefile
index de2eca0279..99c343275b 100644
--- a/lib/diameter/src/Makefile
+++ b/lib/diameter/src/Makefile
@@ -1,7 +1,7 @@
 # 
 # %CopyrightBegin%
 # 
-# Copyright Ericsson AB 2010-2011. All Rights Reserved.
+# Copyright Ericsson AB 2010-2012. All Rights Reserved.
 # 
 # The contents of this file are subject to the Erlang Public License,
 # Version 1.1, (the "License"); you may not use this file except in
@@ -181,6 +181,31 @@ clean:
 	rm -f $(TARGET_FILES) gen/*
 	rm -f depend.mk
 
+realclean: clean
+	rm -f ../ebin/*
+# Not $(EBIN) just to be a bit paranoid
+
+PLT = ./otp.plt
+
+plt:
+	dialyzer --build_plt \
+	         --apps erts stdlib kernel \
+	                xmerl ssl public_key crypto \
+	                compiler syntax_tools runtime_tools \
+	         --output_plt $(PLT) \
+	         --verbose
+
+dialyze: opt $(PLT)
+	dialyzer --plt $(PLT) \
+	         --verbose \
+	         -Wno_improper_lists \
+	         $(EBIN)/diameter_gen_base_rfc3588.$(EMULATOR) \
+	         $(patsubst %, $(EBIN)/%.$(EMULATOR), \
+                          $(notdir $(RT_MODULES) $(CT_MODULES)))
+# Omit all but the common dictionary module since these
+# (diameter_gen_relay in particular) generate warning depending on how
+# much of the included diameter_gen.hrl they use.
+
 # ----------------------------------------------------
 # Release targets
 # ----------------------------------------------------
@@ -245,10 +270,11 @@ depend.mk: depend.sed $(MODULES:%=%.erl) Makefile
 
 -include depend.mk
 
-.PHONY: app clean depend dict info release_subdir
+.PHONY: app clean realclean depend dict info release_subdir
 .PHONY: debug opt release_docs_spec release_spec
 .PHONY: $(TARGET_DIRS:%/=%) $(TARGET_DIRS:%/=release_src_%)
 .PHONY: $(EXAMPLE_DIRS:%/=release_examples_%)
+.PHONY: plt dialyze
 
 # Keep intermediate files.
 .SECONDARY: $(DICT_ERLS) $(DICT_HRLS) gen/$(DICT_YRL:%=%.erl)
diff --git a/lib/diameter/src/base/diameter.appup.src b/lib/diameter/src/base/diameter.appup.src
index 2ebdad598f..9b2a7d18ab 100644
--- a/lib/diameter/src/base/diameter.appup.src
+++ b/lib/diameter/src/base/diameter.appup.src
@@ -2,7 +2,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2011. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2012. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -22,13 +22,28 @@
  [
   {"0.9",  [{restart_application, diameter}]},
   {"0.10", [{restart_application, diameter}]},
-  {"1.0",  [{update, diameter_service},
-            {update, diameter_watchdog}]}
+  {"1.0",  [{restart_application, diameter}]},
+  {"1.1",  [%% new code
+            {add_module, diameter_transport},
+            %% modified code
+            {load, diameter_sctp},
+            {load, diameter_stats},
+            {load, diameter_service},
+            {load, diameter_config},
+            {load, diameter_codec},
+            {load, diameter_watchdog},
+            {load, diameter_peer},
+            {load, diameter_peer_fsm},
+            {load, diameter},
+            %% unmodified but including modified diameter.hrl
+            {load, diameter_callback},
+            {load, diameter_capx},
+            {load, diameter_types}]}
  ],
  [
   {"0.9",  [{restart_application, diameter}]},
   {"0.10", [{restart_application, diameter}]},
-  {"1.0",  [{update, diameter_watchdog},
-            {update, diameter_service}]}
+  {"1.0",  [{restart_application, diameter}]},
+  {"1.1",  [{restart_application, diameter}]}
  ]
 }.
diff --git a/lib/diameter/src/base/diameter.erl b/lib/diameter/src/base/diameter.erl
index 336f0c1f2d..6703841f80 100644
--- a/lib/diameter/src/base/diameter.erl
+++ b/lib/diameter/src/base/diameter.erl
@@ -312,6 +312,7 @@ call(SvcName, App, Message) ->
 -type transport_opt()
    :: {transport_module, atom()}
     | {transport_config, any()}
+    | {transport_timeout, non_neg_integer() | infinity}
     | {applications, [app_alias()]}
     | {capabilities, [capability()]}
     | {capabilities_cb, evaluable()}
diff --git a/lib/diameter/src/base/diameter_codec.erl b/lib/diameter/src/base/diameter_codec.erl
index fe1212b7e0..421e280422 100644
--- a/lib/diameter/src/base/diameter_codec.erl
+++ b/lib/diameter/src/base/diameter_codec.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2011. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2012. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -63,9 +63,9 @@ encode(Mod, #diameter_packet{} = Pkt) ->
         e(Mod, Pkt)
     catch
         error: Reason ->
-            %% Be verbose rather than letting the emulator truncate the
-            %% error report.
-            X = {Reason, ?STACK},
+            %% Be verbose since a crash report may be truncated and
+            %% encode errors are self-inflicted.
+            X = {?MODULE, encode, {Reason, ?STACK}},
             diameter_lib:error_report(X, {?MODULE, encode, [Mod, Pkt]}),
             exit(X)
     end;
@@ -91,7 +91,8 @@ e(_, #diameter_packet{msg = [#diameter_header{} = Hdr | As]} = Pkt) ->
 
     Flags = make_flags(0, Hdr),
 
-    Pkt#diameter_packet{bin = <<Vsn:8, Length:24,
+    Pkt#diameter_packet{header = Hdr,
+                        bin = <<Vsn:8, Length:24,
                                 Flags:8, Code:24,
                                 Aid:32,
                                 Hid:32,
diff --git a/lib/diameter/src/base/diameter_config.erl b/lib/diameter/src/base/diameter_config.erl
index 9253af0de2..e47f63f814 100644
--- a/lib/diameter/src/base/diameter_config.erl
+++ b/lib/diameter/src/base/diameter_config.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2011. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2012. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -519,6 +519,7 @@ rm(SvcName, L) ->
     Refs = lists:map(fun(#transport{ref = R}) -> R end, L),
     case stop_transport(SvcName, Refs) of
         ok ->
+            diameter_stats:flush(Refs),
             lists:foreach(fun delete_object/1, L);
         {error, _} = No ->
             No
@@ -600,7 +601,7 @@ app_acc({application, Opts}, Acc) ->
                    module = init_mod(Mod),
                    init_state = ModS,
                    mutable = init_mutable(M),
-                   answer_errors = init_answers(A)}
+                   options = [{answer_errors, init_answers(A)}]}
      | Acc];
 app_acc(_, Acc) ->
     Acc.
diff --git a/lib/diameter/src/base/diameter_peer.erl b/lib/diameter/src/base/diameter_peer.erl
index 3e78c4caef..a2a1c567d8 100644
--- a/lib/diameter/src/base/diameter_peer.erl
+++ b/lib/diameter/src/base/diameter_peer.erl
@@ -27,12 +27,15 @@
          up/2]).
 
 %% ... and the stack.
--export([start/3,
+-export([start/1,
          send/2,
          close/1,
          abort/1,
          notify/2]).
 
+%% Old interface only called from old code.
+-export([start/3]).  %% < diameter-1.2 (R15B02)
+
 %% Server start.
 -export([start_link/0]).
 
@@ -57,6 +60,11 @@
 %% Server state.
 -record(state, {id = now()}).
 
+%% Default transport_module/config.
+-define(DEFAULT_TMOD, diameter_tcp).
+-define(DEFAULT_TCFG, []).
+-define(DEFAULT_TTMO, infinity).
+
 %%% ---------------------------------------------------------------------------
 %%% # notify/2
 %%% ---------------------------------------------------------------------------
@@ -68,9 +76,108 @@ notify(SvcName, T) ->
 %%% # start/3
 %%% ---------------------------------------------------------------------------
 
-start(T, Opts, #diameter_service{} = Svc) ->
-    {Mod, Cfg} = split_transport(Opts),
-    apply(Mod, start, [T, Svc, Cfg]).
+%% From old code: make is restart.
+start(_T, _Opts, #diameter_service{}) ->
+    {error, restart}.
+
+%%% ---------------------------------------------------------------------------
+%%% # start/1
+%%% ---------------------------------------------------------------------------
+
+-spec start({T, [Opt], #diameter_service{}})
+   -> {TPid, [Addr], Tmo, Data}
+    | {error, [term()]}
+ when T    :: {connect|accept, diameter:transport_ref()},
+      Opt  :: diameter:transport_opt(),
+      TPid :: pid(),
+      Addr :: inet:ip_address(),
+      Tmo  :: non_neg_integer(),
+      Data :: {{T, Mod, Cfg}, [Mod], [{T, [Mod], Cfg}], [Err]},
+      Mod  :: module(),
+      Cfg  :: term(),
+      Err  :: term().
+
+%% Initial start.
+start({T, Opts, #diameter_service{} = Svc}) ->
+    start(T, Svc, pair(Opts, [], []), []);
+
+%% Subsequent start.
+start({#diameter_service{} = Svc, Tmo, {{T, _, Cfg}, Ms, Rest, Errs}}) ->
+    start(T, Ms, Cfg, Svc, Tmo, Rest, Errs).
+
+%% pair/3
+%%
+%% Pair transport modules with config.
+
+%% Another transport_module: accumulate it.
+pair([{transport_module, M} | Rest], Mods, Acc) ->
+    pair(Rest, [M|Mods], Acc);
+
+%% Another transport_config: accumulate another tuple.
+pair([{transport_config = T, C} | Rest], Mods, Acc) ->
+    pair([{T, C, ?DEFAULT_TTMO} | Rest], Mods, Acc);
+pair([{transport_config, C, Tmo} | Rest], Mods, Acc) ->
+    pair(Rest, [], acc({Mods, C, Tmo}, Acc));
+
+pair([_ | Rest], Mods, Acc) ->
+    pair(Rest, Mods, Acc);
+
+%% No transport_module or transport_config: defaults.
+pair([], [], []) ->  
+    [{[?DEFAULT_TMOD], ?DEFAULT_TCFG, ?DEFAULT_TTMO}];
+
+%% One transport_module, one transport_config.
+pair([], [M], [{[], Cfg, Tmo}]) ->
+    [{[M], Cfg, Tmo}];
+
+%% Trailing transport_module: default transport_config.
+pair([], [_|_] = Mods, Acc) ->
+    lists:reverse(acc({Mods, ?DEFAULT_TCFG, ?DEFAULT_TTMO}, Acc));
+
+pair([], [], Acc) ->
+    lists:reverse(def(Acc)).
+
+%% acc/2
+
+acc(T, Acc) ->
+    [T | def(Acc)].
+
+%% def/1
+%%
+%% Default module of previous pair if none were specified.
+
+def([{[], Cfg, Tmo} | Acc]) ->
+    [{[?DEFAULT_TMOD], Cfg, Tmo} | Acc];
+def(Acc) ->
+    Acc.
+
+%% start/4
+
+start(T, Svc, [{Ms, Cfg, Tmo} | Rest], Errs) ->
+    start(T, Ms, Cfg, Svc, Tmo, Rest, Errs);
+
+start(_, _, [], Errs) ->
+    {error, Errs}.
+
+%% start/7
+
+start(T, [], _, Svc, _, Rest, Errs) ->
+    start(T, Svc, Rest, Errs);
+
+start(T, [M|Ms], Cfg, Svc, Tmo, Rest, Errs) ->
+    case start(M, [T, Svc, Cfg]) of
+        {ok, TPid} ->
+            {TPid, [], Tmo, {{T, M, Cfg}, Ms, Rest, Errs}};
+        {ok, TPid, [_|_] = Addrs} ->
+            {TPid, Addrs, Tmo, {{T, M, Cfg}, Ms, Rest, Errs}};
+        E ->
+            start(T, Ms, Cfg, Svc, Tmo, Rest, [E|Errs])
+    end.
+
+%% start/2
+
+start(Mod, Args) ->
+    apply(Mod, start, Args).
 
 %%% ---------------------------------------------------------------------------
 %%% # up/[12]
@@ -204,21 +311,6 @@ bang(undefined = No, _) ->
 bang(Pid, T) ->
     Pid ! T.
 
-%% split_transport/1
-%%
-%% Split options into transport module, transport config and
-%% remaining options.
-
-split_transport(Opts) ->
-    {[M,C], _} = proplists:split(Opts, [transport_module,
-                                        transport_config]),
-    {value(M, diameter_tcp), value(C, [])}.
-
-value([{_,V}], _) ->
-    V;
-value([], V) ->
-    V.
-
 %% call/1
 
 call(Request) ->
diff --git a/lib/diameter/src/base/diameter_peer_fsm.erl b/lib/diameter/src/base/diameter_peer_fsm.erl
index 99644814d2..302540e76b 100644
--- a/lib/diameter/src/base/diameter_peer_fsm.erl
+++ b/lib/diameter/src/base/diameter_peer_fsm.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2011. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2012. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -54,6 +54,12 @@
 -define(NO_INBAND_SECURITY, 0).
 -define(TLS, 1).
 
+%% Keys in process dictionary.
+-define(CB_KEY, cb).       %% capabilities callback
+-define(DWA_KEY, dwa).     %% outgoing DWA
+-define(Q_KEY, q).         %% transport start queue
+-define(START_KEY, start). %% start of connected transport
+
 %% A 2xxx series Result-Code. Not necessarily 2001.
 -define(IS_SUCCESS(N), 2 == (N) div 1000).
 
@@ -115,16 +121,20 @@
 %%% Output: Pid
 %%% ---------------------------------------------------------------------------
 
+-spec start(T, [Opt], #diameter_service{})
+   -> pid()
+ when T   :: {connect|accept, diameter:transport_ref()},
+      Opt :: diameter:transport_opt().
+
 %% diameter_config requires a non-empty list of applications on the
 %% service but diameter_service then constrains the list to any
 %% specified on the transport in question. Check here that the list is
 %% still non-empty.
 
-start({_, Ref} = Type, Opts, #diameter_service{applications = Apps} = Svc) ->
+start({_,_} = Type, Opts, #diameter_service{applications = Apps} = Svc) ->
     [] /= Apps orelse ?ERROR({no_apps, Type, Opts}),
     T = {self(), Type, Opts, Svc},
     {ok, Pid} = diameter_peer_fsm_sup:start_child(T),
-    diameter_stats:reg(Pid, Ref),
     Pid.
 
 start_link(T) ->
@@ -143,18 +153,18 @@ init(T) ->
     proc_lib:init_ack({ok, self()}),
     gen_server:enter_loop(?MODULE, [], i(T)).
 
-i({WPid, T, Opts, #diameter_service{capabilities = Caps} = Svc0}) ->
-    putr(dwa, dwa(Caps)),
+i({WPid, T, Opts, #diameter_service{capabilities = Caps} = Svc}) ->
+    putr(?DWA_KEY, dwa(Caps)),
     {M, Ref} = T,
+    diameter_stats:reg(Ref),
     {[Ts], Rest} = proplists:split(Opts, [capabilities_cb]),
-    putr(capabilities_cb, {Ref, [F || {_,F} <- Ts]}),
-    {ok, TPid, Svc} = start_transport(T, Rest, Svc0),
-    erlang:monitor(process, TPid),
+    putr(?CB_KEY, {Ref, [F || {_,F} <- Ts]}),
     erlang:monitor(process, WPid),
+    {TPid, Addrs} = start_transport(T, Rest, Svc),
     #state{parent = WPid,
            transport = TPid,
            mode = M,
-           service = Svc}.
+           service = svc(Svc, Addrs)}.
 %% The transport returns its local ip addresses so that different
 %% transports on the same service can use different local addresses.
 %% The local addresses are put into Host-IP-Address avps here when
@@ -164,18 +174,56 @@ i({WPid, T, Opts, #diameter_service{capabilities = Caps} = Svc0}) ->
 %% watchdog start (start/2) succeeds regardless so as not to crash the
 %% service.
 
-start_transport(T, Opts, Svc) ->
-    case diameter_peer:start(T, Opts, Svc) of
-        {ok, TPid} ->
-            {ok, TPid, Svc};
-        {ok, TPid, [_|_] = Addrs} ->
-            #diameter_service{capabilities = Caps0} = Svc,
-            Caps = Caps0#diameter_caps{host_ip_address = Addrs},
-            {ok, TPid, Svc#diameter_service{capabilities = Caps}};
+start_transport(T, Opts, #diameter_service{capabilities = Caps} = Svc) ->
+    Addrs0 = Caps#diameter_caps.host_ip_address,
+    start_transport(Addrs0, {T, Opts, Svc}).
+
+start_transport(Addrs0, T) ->
+    case diameter_peer:start(T) of
+        {TPid, Addrs, Tmo, Data} ->
+            erlang:monitor(process, TPid),
+            q_next(TPid, Addrs0, Tmo, Data),
+            {TPid, addrs(Addrs, Addrs0)};
         No ->
             exit({shutdown, No})
     end.
 
+addrs([], Addrs0) ->
+    Addrs0;
+addrs(Addrs, _) ->
+    Addrs.
+
+svc(Svc, []) ->
+    Svc;
+svc(Svc, Addrs) ->
+    readdr(Svc, Addrs).
+
+readdr(#diameter_service{capabilities = Caps0} = Svc, Addrs) ->
+    Caps = Caps0#diameter_caps{host_ip_address = Addrs},
+    Svc#diameter_service{capabilities = Caps}.
+
+%% The 4-tuple Data returned from diameter_peer:start/1 identifies the
+%% transport module/config use to start the transport process in
+%% question as well as any alternates to try if a connection isn't
+%% established within Tmo.
+q_next(TPid, Addrs0, Tmo, {_,_,_,_} = Data) ->
+    send_after(Tmo, {connection_timeout, TPid}),
+    putr(?Q_KEY, {Addrs0, Tmo, Data}).
+
+%% Connection has been established: retain the started
+%% pid/module/config in the process dictionary. This is a part of the
+%% interface defined by this module, so that the transport pid can be
+%% found when constructing service_info (in order to extract further
+%% information from it).
+keep_transport(TPid) ->
+    {_, _, {{_,_,_} = T, _, _, _}} = eraser(?Q_KEY),
+    putr(?START_KEY, {TPid, T}).
+
+send_after(infinity, _) ->
+    ok;
+send_after(Tmo, T) ->
+    erlang:send_after(Tmo, self(), T).
+
 %% handle_call/3
 
 handle_call(_, _, State) ->
@@ -202,14 +250,27 @@ handle_info(T, #state{} = State) ->
             ?LOG(stop, T),
             x(T, State)
     catch
+        exit: {diameter_codec, encode, _} = Reason ->
+            close_wd(Reason, State#state.parent),
+            ?LOG(stop, Reason),
+            %% diameter_codec:encode/2 emits an error report. Only
+            %% indicate the probable reason here.
+            diameter_lib:info_report(probable_configuration_error,
+                                     insufficient_capabilities),
+            {stop, {shutdown, Reason}, State};
         {?MODULE, Tag, Reason}  ->
             ?LOG(Tag, {Reason, T}),
             {stop, {shutdown, Reason}, State}
     end.
-%% The form of the exception caught here is historical. It's
+%% The form of the throw caught here is historical. It's
 %% significant that it's not a 2-tuple, as in ?FAILURE(Reason),
 %% since these are caught elsewhere.
 
+%% Note that there's no guarantee that the service and transport
+%% capabilities are good enough to build a CER/CEA that can be
+%% succesfully encoded. It's not checked at diameter:add_transport/2
+%% since this can be called before creating the service.
+
 x(Reason, #state{} = S) ->
     close_wd(Reason, S),
     {stop, {shutdown, Reason}, S}.
@@ -240,25 +301,48 @@ eraser(Key) ->
 
 %% Connection to peer.
 transition({diameter, {TPid, connected, Remote}},
-           #state{state = PS,
+           #state{transport = TPid,
+                  state = PS,
                   mode = M}
            = S) ->
     'Wait-Conn-Ack' = PS,  %% assert
     connect = M,           %%
-    send_CER(S#state{mode = {M, Remote},
-                     transport = TPid});
+    keep_transport(TPid),
+    send_CER(S#state{mode = {M, Remote}});
 
 %% Connection from peer.
 transition({diameter, {TPid, connected}},
-           #state{state = PS,
+           #state{transport = TPid,
+                  state = PS,
                   mode = M,
                   parent = Pid}
            = S) ->
     'Wait-Conn-Ack' = PS,  %% assert
     accept = M,            %%
+    keep_transport(TPid),
     Pid ! {accepted, self()},
-    start_timer(S#state{state = recv_CER,
-                        transport = TPid});
+    start_timer(S#state{state = recv_CER});
+
+%% Connection established after receiving a connection_timeout
+%% message. This may be followed by an incoming message which arrived
+%% before the transport was killed and this can't be distinguished
+%% from one from the transport that's been started to replace it.
+transition({diameter, {_, connected}}, _) ->
+    {stop, connection_timeout};
+transition({diameter, {_, connected, _}}, _) ->
+    {stop, connection_timeout};
+
+%% Connection has timed out: start an alternate.
+transition({connection_timeout = T, TPid},
+           #state{transport = TPid,
+                  state = 'Wait-Conn-Ack'}
+           = S) ->
+    exit(TPid, {shutdown, T}),
+    start_next(S);
+
+%% Connect timeout after connection or alternate start: ignore.
+transition({connection_timeout, _}, _) ->
+    ok;
 
 %% Incoming message from the transport.
 transition({diameter, {recv, Pkt}}, S) ->
@@ -305,14 +389,21 @@ transition({resolve_port, _Pid} = T, #state{transport = TPid}) ->
     TPid ! T,
     ok;
 
-%% Parent or transport has died.
-transition({'DOWN', _, process, P, _},
-           #state{parent = Pid,
-                  transport = TPid})
-  when P == Pid;
-       P == TPid ->
+%% Parent has died.
+transition({'DOWN', _, process, WPid, _},
+           #state{parent = WPid}) ->
     stop;
 
+%% Transport has died before connection timeout.
+transition({'DOWN', _, process, TPid, _},
+           #state{transport = TPid}
+           = S) ->
+    start_next(S);
+
+%% Transport has died after connection timeout.
+transition({'DOWN', _, process, _, _}, _) ->
+    ok;
+
 %% State query.
 transition({state, Pid}, #state{state = S, transport = TPid}) ->
     Pid ! {self(), [S, TPid]},
@@ -320,6 +411,19 @@ transition({state, Pid}, #state{state = S, transport = TPid}) ->
 
 %% Crash on anything unexpected.
 
+%% start_next/1
+
+start_next(#state{service = Svc0} = S) ->
+    case getr(?Q_KEY) of
+        {Addrs0, Tmo, Data} ->
+            Svc = readdr(Svc0, Addrs0),
+            {TPid, Addrs} = start_transport(Addrs0, {Svc, Tmo, Data}),
+            S#state{transport = TPid,
+                    service = svc(Svc, Addrs)};
+        undefined ->
+            stop
+    end.
+
 %% send_CER/1
 
 send_CER(#state{mode = {connect, Remote},
@@ -649,7 +753,7 @@ rc([RC|_]) ->
 %% answer/2
 
 answer('DWR', _) ->
-    getr(dwa);
+    getr(?DWA_KEY);
 
 answer(Name, #state{service = #diameter_service{capabilities = Caps}}) ->
     a(Name, Caps).
@@ -749,15 +853,15 @@ caps(#state{service = Svc}) ->
 %% caps_cb/1
 
 caps_cb(Caps) ->
-    {Ref, Ts} = eraser(capabilities_cb),
-    ccb(Ts, [Ref, Caps]).
+    {Ref, Ts} = eraser(?CB_KEY),
+    caps_cb(Ts, [Ref, Caps]).
 
-ccb([], _) ->
+caps_cb([], _) ->
     ok;
-ccb([F | Rest], T) ->
+caps_cb([F | Rest], T) ->
     case diameter_lib:eval([F|T]) of
         ok ->
-            ccb(Rest, T);
+            caps_cb(Rest, T);
         N when ?IS_SUCCESS(N) ->  %% 2xxx result code: accept immediately
             N;
         Res ->
diff --git a/lib/diameter/src/base/diameter_service.erl b/lib/diameter/src/base/diameter_service.erl
index 3dfdcee2b2..5b8a399758 100644
--- a/lib/diameter/src/base/diameter_service.erl
+++ b/lib/diameter/src/base/diameter_service.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2011. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2012. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -43,8 +43,7 @@
          subscriptions/0,
          services/0,
          services/1,
-         whois/1,
-         flush_stats/1]).
+         whois/1]).
 
 %% test/debug
 -export([call_module/3,
@@ -65,13 +64,33 @@
 -include_lib("diameter/include/diameter.hrl").
 -include("diameter_internal.hrl").
 
+%% The "old" states maintained in this module historically.
 -define(STATE_UP,   up).
 -define(STATE_DOWN, down).
 
+-type op_state() :: ?STATE_UP
+                  | ?STATE_DOWN.
+
+%% The RFC 3539 watchdog states that are now maintained, albeit
+%% along with the old up/down. okay = up, else down.
+-define(WD_INITIAL, initial).
+-define(WD_OKAY,    okay).
+-define(WD_SUSPECT, suspect).
+-define(WD_DOWN,    down).
+-define(WD_REOPEN,  reopen).
+
+-type wd_state() :: ?WD_INITIAL
+                  | ?WD_OKAY
+                  | ?WD_SUSPECT
+                  | ?WD_DOWN
+                  | ?WD_REOPEN.
+
 -define(DEFAULT_TC,     30000).  %% RFC 3588 ch 2.1
 -define(DEFAULT_TIMEOUT, 5000).  %% for outgoing requests
 -define(RESTART_TC,      1000).  %% if restart was this recent
 
+-define(RELAY, ?DIAMETER_DICT_RELAY).
+
 %% Used to be able to swap this with anything else dict-like but now
 %% rely on the fact that a service's #state{} record does not change
 %% in storing in it ?STATE table and not always going through the
@@ -117,7 +136,8 @@
          type :: match(connect | accept),
          ref  :: match(reference()),  %% key into diameter_config
          options :: match([diameter:transport_opt()]),%% from start_transport
-         op_state = ?STATE_DOWN :: match(?STATE_DOWN | ?STATE_UP),
+         op_state = {?STATE_DOWN, ?WD_INITIAL}
+                 :: match(op_state() | {op_state(), wd_state()}),
          started = now(),      %% at process start
          conn = false :: match(boolean() | pid())}).
                       %% true at accept, pid() at connection_up (connT key)
@@ -388,15 +408,6 @@ whois(SvcName) ->
             undefined
     end.
 
-%%% ---------------------------------------------------------------------------
-%%% # flush_stats/1
-%%%
-%%% Output: list of {{SvcName, Alias, Counter}, Value}
-%%% ---------------------------------------------------------------------------
-
-flush_stats(TPid) ->
-    diameter_stats:flush(TPid).
-
 %% ===========================================================================
 %% ===========================================================================
 
@@ -516,6 +527,34 @@ transition({reconnect, Pid}, S) ->
     reconnect(Pid, S),
     ok;
 
+%% Watchdog is sending notification of a state transition. Note that
+%% the connection_up/down messages are pre-date this message and are
+%% still used. A 'watchdog' message will follow these and communicate
+%% the same state as was set in handling connection_up/down.
+transition({watchdog, Pid, {TPid, From, To}}, #state{service_name = SvcName,
+                                                     peerT = PeerT}) ->
+    #peer{ref = Ref, type = T, options = Opts, op_state = {OS,_}}
+        = P
+        = fetch(PeerT, Pid),
+    insert(PeerT, P#peer{op_state = {OS, To}}),
+    send_event(SvcName, {watchdog, Ref, TPid, {From, To}, {T, Opts}}),
+    ok;
+%% Death of a peer process results in the removal of it's peer and any
+%% associated conn record when 'DOWN' is received (after this) but the
+%% states will be {?STATE_UP, ?WD_DOWN} for a short time. (No real
+%% problem since ?WD_* is only used in service_info.) We set ?WD_OKAY
+%% as a consequence of connection_up since we know a watchdog is
+%% coming. We can't set anything at connection_down since we don't
+%% know if the subsequent watchdog message will be ?WD_DOWN or
+%% ?WD_SUSPECT. We don't (yet) set ?STATE_* as a consequence of a
+%% watchdog message since this requires changing some of the matching
+%% on ?STATE_*.
+%%
+%% Death of a conn process results in connection_down followed by
+%% watchdog ?WD_DOWN. The latter doesn't result in the conn record
+%% being deleted since 'DOWN' from death of its peer doesn't (yet)
+%% deal with the record having been removed.
+
 %% Monitor process has died. Just die with a reason that tells
 %% diameter_config about the happening. If a cleaner shutdown is
 %% required then someone should stop us.
@@ -879,7 +918,14 @@ accepted(Pid, _TPid, #state{peerT = PeerT} = S) ->
 
 fetch(Tid, Key) ->
     [T] = ets:lookup(Tid, Key),
-    T.
+    case T of
+        #peer{op_state = ?STATE_UP} = P ->
+            P#peer{op_state = {?STATE_UP, ?WD_OKAY}};
+        #peer{op_state = ?STATE_DOWN} = P ->
+            P#peer{op_state = {?STATE_DOWN, ?WD_DOWN}};
+        _ ->
+            T
+    end.
 
 %%% ---------------------------------------------------------------------------
 %%% # connection_up/3
@@ -925,12 +971,12 @@ connection_up(T, P, C, #state{peerT = PeerT,
                               service
                               = #diameter_service{applications = Apps}}
                        = S) ->
-    #peer{conn = TPid, op_state = ?STATE_DOWN}
+    #peer{conn = TPid, op_state = {?STATE_DOWN, _}}
         = P,
     #conn{apps = SApps, caps = Caps}
         = C,
 
-    insert(PeerT, P#peer{op_state = ?STATE_UP}),
+    insert(PeerT, P#peer{op_state = {?STATE_UP, ?WD_OKAY}}),
 
     request_peer_up(TPid),
     report_status(up, P, C, S, T),
@@ -945,27 +991,35 @@ ilp({Id, Alias}, {TC, SA}, LDict) ->
     init_conn(Id, Alias, TC, SA),
     ?Dict:append(Alias, TC, LDict).
 
-init_conn(Id, Alias, TC, {SvcName, Apps}) ->
+init_conn(Id, Alias, {TPid, _} = TC, {SvcName, Apps}) ->
     #diameter_app{module = ModX,
                   id = Id}  %% assert
         = find_app(Alias, Apps),
 
-    peer_cb({ModX, peer_up, [SvcName, TC]}, Alias).
+    peer_cb({ModX, peer_up, [SvcName, TC]}, Alias)
+        orelse exit(TPid, kill).  %% fake transport failure
+
+%% find_app/2
 
 find_app(Alias, Apps) ->
-    lists:keyfind(Alias, #diameter_app.alias, Apps).
+    case lists:keyfind(Alias, #diameter_app.alias, Apps) of
+        #diameter_app{options = E} = A when is_atom(E) ->  %% upgrade
+            A#diameter_app{options = [{answer_errors, E}]};
+        A ->
+            A
+    end.
 
-%% A failing peer callback brings down the service. In the case of
-%% peer_up we could just kill the transport and emit an error but for
-%% peer_down we have no way to cleanup any state change that peer_up
-%% may have introduced.
+%% Don't bring down the service (and all associated connections)
+%% regardless of what happens.
 peer_cb(MFA, Alias) ->
     try state_cb(MFA, Alias) of
         ModS ->
-            mod_state(Alias, ModS)
+            mod_state(Alias, ModS),
+            true
     catch
-        E: Reason ->
-            ?ERROR({E, Reason, MFA, ?STACK})
+        E:R ->
+            diameter_lib:error_report({failure, {E, R, Alias, ?STACK}}, MFA),
+            false
     end.
 
 %%% ---------------------------------------------------------------------------
@@ -979,22 +1033,22 @@ peer_cb(MFA, Alias) ->
 connection_down(Pid, #state{peerT = PeerT,
                             connT = ConnT}
                      = S) ->
-    #peer{op_state = ?STATE_UP,  %% assert
+    #peer{op_state = {?STATE_UP, WS},  %% assert
           conn = TPid}
         = P
         = fetch(PeerT, Pid),
 
     C = fetch(ConnT, TPid),
-    insert(PeerT, P#peer{op_state = ?STATE_DOWN}),
+    insert(PeerT, P#peer{op_state = {?STATE_DOWN, WS}}),
     connection_down(P,C,S).
 
 %% connection_down/3
 
-connection_down(#peer{op_state = ?STATE_DOWN}, _, S) ->
+connection_down(#peer{op_state = {?STATE_DOWN, _}}, _, S) ->
     S;
 
 connection_down(#peer{conn = TPid,
-                      op_state = ?STATE_UP}
+                      op_state = {?STATE_UP, _}}
                 = P,
                 #conn{caps = Caps,
                       apps = SApps}
@@ -1043,7 +1097,7 @@ peer_down(Pid, Reason, #state{peerT = PeerT} = S) ->
 
 %% Send an event at connection establishment failure.
 closed({shutdown, {close, _TPid, Reason}},
-       #peer{op_state = ?STATE_DOWN,
+       #peer{op_state = {?STATE_DOWN, _},
              ref = Ref,
              type = Type,
              options = Opts},
@@ -1352,7 +1406,7 @@ send_request(Pkt, TPid, Caps, App, Opts, Caller, SvcName) ->
     #diameter_app{alias = Alias,
                   dictionary = Dict,
                   module = ModX,
-                  answer_errors = AE}
+                  options = [{answer_errors, AE} | _]}
         = App,
 
     EPkt = encode(Dict, Pkt),
@@ -1935,6 +1989,12 @@ is_loop(Code, Vid, OH, Avps) ->
 %%
 %% Send a locally originating reply.
 
+%% Skip the setting of Result-Code and Failed-AVP's below.
+reply([Msg], Dict, TPid, Pkt)
+  when is_list(Msg);
+       is_tuple(Msg) ->
+    reply(Msg, Dict, TPid, Pkt#diameter_packet{errors = []});
+
 %% No errors or a diameter_header/avp list.
 reply(Msg, Dict, TPid, #diameter_packet{errors = Es,
                                         transport_data = TD}
@@ -1942,7 +2002,7 @@ reply(Msg, Dict, TPid, #diameter_packet{errors = Es,
   when [] == Es;
        is_record(hd(Msg), diameter_header) ->
     Pkt = diameter_codec:encode(Dict, make_answer_packet(Msg, ReqPkt)),
-    incr(send, Pkt, TPid),  %% count result codes in sent answers
+    incr(send, Pkt, Dict, TPid),  %% count result codes in sent answers
     send(TPid, Pkt#diameter_packet{transport_data = TD});
 
 %% Or not: set Result-Code and Failed-AVP AVP's.
@@ -1983,7 +2043,10 @@ rc(RC) ->
 
 rc(Rec, RC, Failed, Dict)
   when is_integer(RC) ->
-    set(Rec, [{'Result-Code', RC} | failed_avp(Rec, Failed, Dict)], Dict).
+    set(Rec,
+        lists:append([rc(Rec, {'Result-Code', RC}, Dict),
+                      failed_avp(Rec, Failed, Dict)]),
+        Dict).
 
 %% Reply as name and tuple list ...
 set([_|_] = Ans, Avps, _) ->
@@ -1993,6 +2056,22 @@ set([_|_] = Ans, Avps, _) ->
 set(Rec, Avps, Dict) ->
     Dict:'#set-'(Avps, Rec).
 
+%% rc/3
+%%
+%% Turn the result code into a list if its optional and only set it if
+%% the arity is 1 or {0,1}. In other cases (which probably shouldn't
+%% exist in practise) we can't know what's appropriate.
+
+rc([MsgName | _], {'Result-Code' = K, RC} = T, Dict) ->
+    case Dict:avp_arity(MsgName, 'Result-Code') of
+        1     -> [T];
+        {0,1} -> [{K, [RC]}];
+        _     -> []
+    end;
+
+rc(Rec, T, Dict) ->
+    rc([Dict:rec2msg(element(1, Rec))], T, Dict).
+    
 %% failed_avp/3
 
 failed_avp(_, [] = No, _) ->
@@ -2200,44 +2279,39 @@ handle_answer(SvcName, _, {error, Req, Reason}) ->
 handle_answer(SvcName,
               AnswerErrors,
               {answer, #request{dictionary = Dict} = Req, Pkt}) ->
-    a(examine(diameter_codec:decode(Dict, Pkt)),
-      SvcName,
-      AnswerErrors,
-      Req).
+    answer(examine(diameter_codec:decode(Dict, Pkt)),
+           SvcName,
+           AnswerErrors,
+           Req).
 
 %% We don't really need to do a full decode if we're a relay and will
 %% just resend with a new hop by hop identifier, but might a proxy
 %% want to examine the answer?
 
-a(#diameter_packet{errors = []}
-  = Pkt,
-  SvcName,
-  AE,
-  #request{transport = TPid,
-           caps = Caps,
-           packet = P}
-  = Req) ->
+answer(Pkt, SvcName, AE, #request{transport = TPid,
+                                  dictionary = Dict}
+                         = Req) ->
     try
-        incr(in, Pkt, TPid)
+        incr(recv, Pkt, Dict, TPid)
     of
-        _ ->
-            cb(Req, handle_answer, [Pkt, msg(P), SvcName, {TPid, Caps}])
+        _ -> a(Pkt, SvcName, AE, Req)
     catch
         exit: {invalid_error_bit, _} = E ->
-            e(Pkt#diameter_packet{errors = [E]}, SvcName, AE, Req)
-    end;
-
-a(#diameter_packet{} = Pkt, SvcName, AE, Req) ->
-    e(Pkt, SvcName, AE, Req).
+            a(Pkt#diameter_packet{errors = [E]}, SvcName, AE, Req)
+    end.
 
-e(Pkt, SvcName, callback, #request{transport = TPid,
-                                   caps = Caps,
-                                   packet = Pkt}
-                          = Req) ->
-    cb(Req, handle_answer, [Pkt, msg(Pkt), SvcName, {TPid, Caps}]);
-e(Pkt, SvcName, report, Req) ->
+a(#diameter_packet{errors = Es} = Pkt, SvcName, AE, #request{transport = TPid,
+                                                             caps = Caps,
+                                                             packet = P}
+                                                    = Req)
+  when [] == Es;
+       callback == AE ->
+    cb(Req, handle_answer, [Pkt, msg(P), SvcName, {TPid, Caps}]);
+    
+a(Pkt, SvcName, report, Req) ->
     x(errors, handle_answer, [SvcName, Req, Pkt]);
-e(Pkt, SvcName, discard, Req) ->
+
+a(Pkt, SvcName, discard, Req) ->
     x({errors, handle_answer, [SvcName, Req, Pkt]}).
 
 %% Note that we don't check that the application id in the answer's
@@ -2249,17 +2323,19 @@ e(Pkt, SvcName, discard, Req) ->
 %% Increment a stats counter for an incoming or outgoing message.
 
 %% TODO: fix
-incr(_, #diameter_packet{msg = undefined}, _) ->
+incr(_, #diameter_packet{msg = undefined}, _, _) ->
     ok;
 
-incr(Dir, Pkt, TPid)
-  when is_pid(TPid) ->
+incr(recv = D, #diameter_packet{header = H, errors = [_|_]}, _, TPid) ->
+    incr(TPid, {diameter_codec:msg_id(H), D, error});
+
+incr(Dir, Pkt, Dict, TPid) ->
     #diameter_packet{header = #diameter_header{is_error = E}
                             = Hdr,
                      msg = Rec}
         = Pkt,
 
-    RC = int(get_avp_value(?BASE, 'Result-Code', Rec)),
+    RC = int(get_avp_value(Dict, 'Result-Code', Rec)),
     PE = is_protocol_error(RC),
 
     %% Check that the E bit is set only for 3xxx result codes.
@@ -2267,15 +2343,21 @@ incr(Dir, Pkt, TPid)
         orelse (E andalso PE)
         orelse x({invalid_error_bit, RC}, answer, [Dir, Pkt]),
 
-    Ctr = rc_counter(Rec, RC),
-    is_tuple(Ctr)
-        andalso incr(TPid, {diameter_codec:msg_id(Hdr), Dir, Ctr}).
+    irc(TPid, Hdr, Dir, rc_counter(Dict, Rec, RC)).
+
+irc(_, _, _, undefined) ->
+    false;
+
+irc(TPid, Hdr, Dir, Ctr) ->
+    incr(TPid, {diameter_codec:msg_id(Hdr), Dir, Ctr}).
 
 %% incr/2
 
 incr(TPid, Counter) ->
     diameter_stats:incr(Counter, TPid, 1).
 
+%% error_counter/2
+
 %% RFC 3588, 7.6:
 %%
 %%   All Diameter answer messages defined in vendor-specific
@@ -2285,26 +2367,27 @@ incr(TPid, Counter) ->
 %% Maintain statistics assuming one or the other, not both, which is
 %% surely the intent of the RFC.
 
-rc_counter(_, RC)
-  when is_integer(RC) ->
-    {'Result-Code', RC};
-rc_counter(Rec, _) ->
-    rcc(get_avp_value(?BASE, 'Experimental-Result', Rec)).
+rc_counter(Dict, Rec, undefined) ->
+    er(get_avp_value(Dict, 'Experimental-Result', Rec));
+rc_counter(_, _, RC) ->
+    {'Result-Code', RC}.
 
 %% Outgoing answers may be in any of the forms messages can be sent
 %% in. Incoming messages will be records. We're assuming here that the
 %% arity of the result code AVP's is 0 or 1.
 
-rcc([{_,_,RC} = T])
-  when is_integer(RC) ->
+er([{_,_,N} = T | _])
+  when is_integer(N) ->
     T;
-rcc({_,_,RC} = T)
-  when is_integer(RC) ->
+er({_,_,N} = T)
+  when is_integer(N) ->
     T;
-rcc(_) ->
+er(_) ->
     undefined.
 
-int([N])
+%% Extract the first good looking integer. There's no guarantee
+%% that what we're looking for has arity 1.
+int([N|_])
   when is_integer(N) ->
     N;
 int(N)
@@ -2349,8 +2432,11 @@ rt(#request{packet = #diameter_packet{msg = undefined}}, _) ->
     false;  %% TODO: Not what we should do.
 
 %% ... or not.
-rt(#request{packet = #diameter_packet{msg = Msg}} = Req, S) ->
-    find_transport(get_destination(Msg), Req, S).
+rt(#request{packet = #diameter_packet{msg = Msg},
+            dictionary = Dict}
+   = Req,
+   S) ->
+    find_transport(get_destination(Dict, Msg), Req, S).
 
 %%% ---------------------------------------------------------------------------
 %%% # report_status/5
@@ -2462,12 +2548,12 @@ find_transport({alias, Alias}, Msg, Opts, #state{service = Svc} = S) ->
 find_transport(#diameter_app{} = App, Msg, Opts, S) ->
     ft(App, Msg, Opts, S).
 
-ft(#diameter_app{module = Mod} = App, Msg, Opts, S) ->
+ft(#diameter_app{module = Mod, dictionary = Dict} = App, Msg, Opts, S) ->
     #options{filter = Filter,
              extra = Xtra}
         = Opts,
     pick_peer(App#diameter_app{module = Mod ++ Xtra},
-              get_destination(Msg),
+              get_destination(Dict, Msg),
               Filter,
               S);
 ft(false = No, _, _, _) ->
@@ -2503,11 +2589,11 @@ find_transport([_,_] = RH,
               Filter,
               S).
 
-%% get_destination/1
+%% get_destination/2
 
-get_destination(Msg) ->
-    [str(get_avp_value(?BASE, 'Destination-Realm', Msg)),
-     str(get_avp_value(?BASE, 'Destination-Host', Msg))].
+get_destination(Dict, Msg) ->
+    [str(get_avp_value(Dict, 'Destination-Realm', Msg)),
+     str(get_avp_value(Dict, 'Destination-Host', Msg))].
 
 %% This is not entirely correct. The avp could have an arity 1, in
 %% which case an empty list is a DiameterIdentity of length 0 rather
@@ -2531,6 +2617,9 @@ str(T) ->
 %% question. The third form allows messages to be sent as is, without
 %% a dictionary, which is needed in the case of relay agents, for one.
 
+get_avp_value(?RELAY, Name, Msg) ->
+    get_avp_value(?BASE, Name, Msg);
+
 get_avp_value(Dict, Name, [#diameter_header{} | Avps]) ->
     try
         {Code, _, VId} = Dict:avp_header(Name),
@@ -2746,20 +2835,45 @@ transports(#state{peerT = PeerT}) ->
                    'Vendor-Specific-Application-Id',
                    'Firmware-Revision']).
 
+%% The config returned by diameter:service_info(SvcName, all).
 -define(ALL_INFO, [capabilities,
                    applications,
                    transport,
-                   pending,
-                   statistics]).
+                   pending]).
+
+%% The rest.
+-define(OTHER_INFO, [connections,
+                     name,
+                     peers,
+                     statistics]).
 
-service_info(Items, S)
-  when is_list(Items) ->
-    [{complete(I), service_info(I,S)} || I <- Items];
 service_info(Item, S)
   when is_atom(Item) ->
-    service_info(Item, S, true).
+    case tagged_info(Item, S) of
+        {_, T} -> T;
+        undefined = No -> No
+    end;
+
+service_info(Items, S) ->
+    tagged_info(Items, S).
 
-service_info(Item, #state{service = Svc} = S, Complete) ->
+tagged_info(Item, S)
+  when is_atom(Item) ->
+    case complete(Item) of
+        {value, I} ->
+            {I, complete_info(I,S)};
+        false ->
+            undefined
+    end;
+
+tagged_info(Items, S)
+  when is_list(Items) ->
+    [T || I <- Items, T <- [tagged_info(I,S)], T /= undefined, T /= []];
+
+tagged_info(_, _) ->
+    undefined.
+
+complete_info(Item, #state{service = Svc} = S) ->
     case Item of
         name ->
             S#state.service_name;
@@ -2803,70 +2917,119 @@ service_info(Item, #state{service = Svc} = S, Complete) ->
         applications -> info_apps(S);
         transport    -> info_transport(S);
         pending      -> info_pending(S);
-        statistics   -> info_stats(S);
-        keys         -> ?ALL_INFO ++ ?CAP_INFO;  %% mostly for test
+        keys         -> ?ALL_INFO ++ ?CAP_INFO ++ ?OTHER_INFO;
         all          -> service_info(?ALL_INFO, S);
-        _ when Complete   -> service_info(complete(Item), S, false);
-        _            -> undefined
+        statistics   -> info_stats(S);
+        connections  -> info_connections(S);
+        peers        -> info_peers(S)
     end.
 
+complete(I)
+  when I == keys;
+       I == all ->
+    {value, I};
 complete(Pre) ->
     P = atom_to_list(Pre),
-    case [I || I <- [name | ?ALL_INFO] ++ ?CAP_INFO,
+    case [I || I <- ?ALL_INFO ++ ?CAP_INFO ++ ?OTHER_INFO,
                lists:prefix(P, atom_to_list(I))]
     of
-        [I] -> I;
-        _   -> Pre
+        [I] -> {value, I};
+        _   -> false
     end.
 
+%% info_stats/1
+
 info_stats(#state{peerT = PeerT}) ->
-    Peers = ets:select(PeerT, [{#peer{ref = '$1', conn = '$2', _ = '_'},
-                                [{'is_pid', '$2'}],
-                                [['$1', '$2']]}]),
-    diameter_stats:read(lists:append(Peers)).
-%% TODO: include peer identities in return value
-
-info_transport(#state{peerT = PeerT, connT = ConnT}) ->
-    dict:fold(fun it/3,
+    MatchSpec = [{#peer{ref = '$1', conn = '$2', _ = '_'},
+                  [{'is_pid', '$2'}],
+                  [['$1', '$2']]}],
+    diameter_stats:read(lists:append(ets:select(PeerT, MatchSpec))).
+
+%% info_transport/1
+%%
+%% One entry per configured transport. Statistics for each entry are
+%% the accumulated values for the ref and associated peer pids.
+
+info_transport(S) ->
+    PeerD = peer_dict(S),
+    RefsD = dict:map(fun(_, Ls) -> [P || L <- Ls, {peer, {P,_}} <- L] end,
+                     PeerD),
+    Refs = lists:append(dict:fold(fun(R, Ps, A) -> [[R|Ps] | A] end,
+                                  [],
+                                  RefsD)),
+    Stats = diameter_stats:read(Refs),
+    dict:fold(fun(R, Ls, A) ->
+                      Ps = dict:fetch(R, RefsD),
+                      [[{ref, R} | transport(Ls)] ++ [stats([R|Ps], Stats)]
+                       | A]
+              end,
               [],
-              ets:foldl(fun(T,A) -> it_acc(ConnT, A, T) end,
-                        dict:new(),
-                        PeerT)).
-
-it(Ref, [[{type, connect} | _] = L], Acc) ->
-    [[{ref, Ref} | L] | Acc];
-it(Ref, [[{type, accept}, {options, Opts} | _] | _] = L, Acc) ->
-    [[{ref, Ref},
-      {type, listen},
-      {options, Opts},
-      {accept, [lists:nthtail(2,A) || A <- L]}]
-     | Acc].
-%% Each entry has the same Opts. (TODO)
-
-it_acc(ConnT, Acc, #peer{pid = Pid,
-                         type = Type,
-                         ref = Ref,
-                         options = Opts,
-                         op_state = OS,
-                         started = T,
-                         conn = TPid}) ->
+              PeerD).
+
+transport([[{type, connect} | _] = L]) ->
+    L;
+
+transport([[{type, accept}, {options, Opts} | _] | _] = Ls) ->
+    [{type, listen},
+     {options, Opts},
+     {accept, [lists:nthtail(2,L) || L <- Ls]}].
+%% Note that all peer records for a listening transport (ie. same Ref)
+%% have the same options. (TODO)
+
+peer_dict(#state{peerT = PeerT, connT = ConnT}) ->
+    ets:foldl(fun(T,A) -> peer_acc(ConnT, A, T) end, dict:new(), PeerT).
+
+peer_acc(ConnT, Acc, #peer{pid = Pid,
+                           type = Type,
+                           ref = Ref,
+                           options = Opts,
+                           op_state = OS,
+                           started = T,
+                           conn = TPid}) ->
+    WS = wd_state(OS),
     dict:append(Ref,
                 [{type, Type},
                  {options, Opts},
-                 {watchdog, {Pid, T, OS}}
-                 | info_conn(ConnT, TPid)],
+                 {watchdog, {Pid, T, WS}}
+                 | info_conn(ConnT, TPid, WS /= ?WD_DOWN)],
                 Acc).
 
-info_conn(ConnT, TPid) ->
-    info_conn(ets:lookup(ConnT, TPid)).
+info_conn(ConnT, TPid, true)
+  when is_pid(TPid) ->
+    info_conn(ets:lookup(ConnT, TPid));
+info_conn(_, _, _) ->
+    [].
+
+wd_state({_,S}) ->
+    S;
+wd_state(?STATE_UP) ->
+    ?WD_OKAY;
+wd_state(?STATE_DOWN) ->
+    ?WD_DOWN.
 
 info_conn([#conn{pid = Pid, apps = SApps, caps = Caps, started = T}]) ->
     [{peer, {Pid, T}},
      {apps, SApps},
-     {caps, info_caps(Caps)}];
+     {caps, info_caps(Caps)}
+     | try [{port, info_port(Pid)}] catch _:_ -> [] end];
 info_conn([] = No) ->
     No.
 
+%% Extract information that the processes involved are expected to
+%% "publish" in their process dictionaries. Simple but backhanded.
+info_port(Pid) ->
+    {_, PD} = process_info(Pid, dictionary),
+    {_, T} = lists:keyfind({diameter_peer_fsm, start}, 1, PD),
+    {TPid, {_Type, TMod, _Cfg}} = T,
+    {_, TD} = process_info(TPid, dictionary),
+    {_, Data} = lists:keyfind({TMod, info}, 1, TD),
+    [{owner, TPid}, {module, TMod} | [_|_] = TMod:info(Data)].
+
+%% Use the fields names from diameter_caps instead of
+%% diameter_base_CER to distinguish between the 2-tuple values
+%% compared to the single capabilities values. Note also that the
+%% returned list is tagged 'caps' rather than 'capabilities' to
+%% emphasize the difference.
 info_caps(#diameter_caps{} = C) ->
     lists:zip(record_info(fields, diameter_caps), tl(tuple_to_list(C))).
 
@@ -2882,6 +3045,10 @@ mk_app(#diameter_app{alias = Alias,
      {module, ModX},
      {id, Id}].
 
+%% info_pending/1
+%%
+%% One entry for each outgoing request whose answer is outstanding.
+
 info_pending(#state{} = S) ->
     MatchSpec = [{{'$1',
                    #request{transport = '$2',
@@ -2895,3 +3062,59 @@ info_pending(#state{} = S) ->
                             {{from, '$3'}}]}}]}],
 
     ets:select(?REQUEST_TABLE, MatchSpec).
+
+%% info_connections/1
+%%
+%% One entry per transport connection. Statistics for each entry are
+%% for the peer pid only.
+
+info_connections(S) ->
+    ConnL = conn_list(S),
+    Stats = diameter_stats:read([P || L <- ConnL, {peer, {P,_}} <- L]),
+    [L ++ [stats([P], Stats)] || L <- ConnL, {peer, {P,_}} <- L].
+
+conn_list(S) ->
+    lists:append(dict:fold(fun conn_acc/3, [], peer_dict(S))).
+
+conn_acc(Ref, Peers, Acc) ->
+    [[[{ref, Ref} | L] || L <- Peers, lists:keymember(peer, 1, L)]
+     | Acc].
+
+stats(Refs, Stats) ->
+    {statistics, dict:to_list(lists:foldl(fun(R,D) ->
+                                                  stats_acc(R, D, Stats)
+                                          end,
+                                          dict:new(),
+                                          Refs))}.
+
+stats_acc(Ref, Dict, Stats) ->
+    lists:foldl(fun({C,N}, D) -> dict:update_counter(C, N, D) end,
+                Dict,
+                proplists:get_value(Ref, Stats, [])).
+
+%% info_peers/1
+%%
+%% One entry per peer Origin-Host. Statistics for each entry are
+%% accumulated values for all associated transport refs and peer pids.
+
+info_peers(S) ->
+    ConnL = conn_list(S),
+    {PeerD, RefD} = lists:foldl(fun peer_acc/2,
+                                {dict:new(), dict:new()},
+                                ConnL),
+    Refs = lists:append(dict:fold(fun(_, Rs, A) -> [lists:append(Rs) | A] end,
+                                  [],
+                                  RefD)),
+    Stats = diameter_stats:read(Refs),
+    dict:fold(fun(OH, Cs, A) ->
+                      Rs = lists:append(dict:fetch(OH, RefD)),
+                      [{OH, [{connections, Cs}, stats(Rs, Stats)]}
+                       | A]
+              end,
+              [],
+              PeerD).
+
+peer_acc(Peer, {PeerD, RefD}) ->
+    [Ref, {TPid, _}, [{origin_host, {_, OH}} | _]]
+        = [proplists:get_value(K, Peer) || K <- [ref, peer, caps]],
+    {dict:append(OH, Peer, PeerD), dict:append(OH, [Ref, TPid], RefD)}.
diff --git a/lib/diameter/src/base/diameter_stats.erl b/lib/diameter/src/base/diameter_stats.erl
index 71479afa95..70727d068e 100644
--- a/lib/diameter/src/base/diameter_stats.erl
+++ b/lib/diameter/src/base/diameter_stats.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2011. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2012. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -22,14 +22,13 @@
 %%
 
 -module(diameter_stats).
--compile({no_auto_import, [monitor/2]}).
 
 -behaviour(gen_server).
 
--export([reg/1, reg/2,
-         incr/1, incr/2, incr/3,
+-export([reg/2, reg/1,
+         incr/3, incr/1,
          read/1,
-         flush/0, flush/1]).
+         flush/1]).
 
 %% supervisor callback
 -export([start_link/0]).
@@ -48,123 +47,105 @@
 
 -include("diameter_internal.hrl").
 
-%% ets table containing stats. reg(Pid, Ref) inserts a {Pid, Ref},
-%% incr(Counter, X, N) updates the counter keyed at {Counter, X}, and
-%% Pid death causes counters keyed on {Counter, Pid} to be deleted and
-%% added to those keyed on {Counter, Ref}.
+%% ets table containing 2-tuple stats. reg(Pid, Ref) inserts a {Pid,
+%% Ref}, incr(Counter, X, N) updates the counter keyed at {Counter,
+%% X}, and Pid death causes counters keyed on {Counter, Pid} to be
+%% deleted and added to those keyed on {Counter, Ref}.
 -define(TABLE, ?MODULE).
 
 %% Name of registered server.
 -define(SERVER, ?MODULE).
 
-%% Entries in the table.
--define(REC(Key, Value), {Key, Value}).
-
 %% Server state.
 -record(state, {id = now()}).
 
 -type counter() :: any().
--type contrib() :: any().
-
-%%% ---------------------------------------------------------------------------
-%%% # reg(Pid, Contrib)
-%%%
-%%% Description: Register a process as a contributor of statistics
-%%%              associated with a specified term. Statistics can be
-%%%              contributed by specifying either Pid or Contrib as
-%%%              the second argument to incr/3. Statistics contributed
-%%%              by Pid are folded into the corresponding entry for
-%%%              Contrib when the process dies.
-%%%
-%%%              Contrib can be any term but should not be a pid
-%%%              passed as the first argument to reg/2. Subsequent
-%%%              registrations for the same Pid overwrite the association
-%%% ---------------------------------------------------------------------------
-
--spec reg(pid(), contrib())
-   -> true.
+-type ref() :: any().
+
+%% ---------------------------------------------------------------------------
+%% # reg(Pid, Ref)
+%%
+%% Register a process as a contributor of statistics associated with a
+%% specified term. Statistics can be contributed by specifying either
+%% Pid or Ref as the second argument to incr/3. Statistics contributed
+%% by Pid are folded into the corresponding entry for Ref when the
+%% process dies.
+%% ---------------------------------------------------------------------------
+
+-spec reg(pid(), ref())
+   -> boolean().
 
-reg(Pid, Contrib)
+reg(Pid, Ref)
   when is_pid(Pid) ->
-    call({reg, Pid, Contrib}).
+    call({reg, Pid, Ref}).
 
--spec reg(contrib())
+-spec reg(ref())
    -> true.
 
 reg(Ref) ->
     reg(self(), Ref).
 
-%%% ---------------------------------------------------------------------------
-%%% # incr(Counter, Contrib, N)
-%%%
-%%% Description: Increment a counter for the specified contributor.
-%%%
-%%%              Contrib will typically be an argument passed to reg/2
-%%%              but there's nothing that requires this. In particular,
-%%%              if Contrib is a pid that hasn't been registered then
-%%%              counters are unaffected by the death of the process.
-%%% ---------------------------------------------------------------------------
-
--spec incr(counter(), contrib(), integer())
-   -> integer().
+%% ---------------------------------------------------------------------------
+%% # incr(Counter, Ref, N)
+%%
+%% Increment a counter for the specified contributor.
+%%
+%% Ref will typically be an argument passed to reg/2 but there's
+%% nothing that requires this. Only registered pids can contribute
+%% counters however, otherwise incr/3 is a no-op.
+%% ---------------------------------------------------------------------------
 
-incr(Ctr, Contrib, N) ->
-    update_counter({Ctr, Contrib}, N).
+-spec incr(counter(), ref(), integer())
+   -> integer() | false.
 
-incr(Ctr, N)
+incr(Ctr, Ref, N)
   when is_integer(N) ->
-    incr(Ctr, self(), N);
-
-incr(Ctr, Contrib) ->
-    incr(Ctr, Contrib, 1).
+    update_counter({Ctr, Ref}, N).
 
 incr(Ctr) ->
     incr(Ctr, self(), 1).
 
-%%% ---------------------------------------------------------------------------
-%%% # read(Contribs)
-%%%
-%%% Description: Retrieve counters for the specified contributors.
-%%% ---------------------------------------------------------------------------
+%% ---------------------------------------------------------------------------
+%% # read(Refs)
+%%
+%% Retrieve counters for the specified contributors.
+%% ---------------------------------------------------------------------------
 
--spec read([contrib()])
-   -> [{contrib(), [{counter(), integer()}]}].
+-spec read([ref()])
+   -> [{ref(), [{counter(), integer()}]}].
 
-read(Contribs) ->
-    lists:foldl(fun(?REC({T,C}, N), D) -> orddict:append(C, {T,N}, D) end,
+read(Refs) ->
+    read(Refs, false).
+
+read(Refs, B) ->
+    MatchSpec = [{{{'_', '$1'}, '_'},
+                  [?ORCOND([{'=:=', '$1', {const, R}}
+                            || R <- Refs])],
+                  ['$_']}],
+    L = ets:select(?TABLE, MatchSpec),
+    B andalso delete(L),
+    lists:foldl(fun({{C,R}, N}, D) -> orddict:append(R, {C,N}, D) end,
                 orddict:new(),
-                ets:select(?TABLE, [{?REC({'_', '$1'}, '_'),
-                                     [?ORCOND([{'=:=', '$1', {const, C}}
-                                               || C <- Contribs])],
-                                     ['$_']}])).
-
-%%% ---------------------------------------------------------------------------
-%%% # flush(Contrib)
-%%%
-%%% Description: Retrieve and delete statistics for the specified
-%%%              contributor.
-%%%
-%%%              If Contrib is a pid registered with reg/2 then statistics
-%%%              for both and its associated contributor are retrieved.
-%%% ---------------------------------------------------------------------------
-
--spec flush(contrib())
-   -> [{counter(), integer()}].
+                L).
+
+%% ---------------------------------------------------------------------------
+%% # flush(Refs)
+%%
+%% Retrieve and delete statistics for the specified contributors.
+%% ---------------------------------------------------------------------------
+
+-spec flush([ref()])
+   -> [{ref(), {counter(), integer()}}].
                    
-flush(Contrib) ->
+flush(Refs) ->
     try
-        call({flush, Contrib})
+        call({flush, Refs})
     catch
         exit: _ ->
             []
     end.
 
-flush() ->
-    flush(self()).
-
-%%% ---------------------------------------------------------
-%%% EXPORTED INTERNAL FUNCTIONS
-%%% ---------------------------------------------------------
+%% ===========================================================================
 
 start_link() ->
     ServerName = {local, ?SERVER},
@@ -179,18 +160,16 @@ state() ->
 uptime() ->
     call(uptime).
 
-%%% ----------------------------------------------------------
-%%% # init(_)
-%%%
-%%% Output: {ok, State}
-%%% ----------------------------------------------------------
+%% ----------------------------------------------------------
+%% # init/1
+%% ----------------------------------------------------------
 
 init([]) ->
     ets:new(?TABLE, [named_table, ordered_set, public]),
     {ok, #state{}}.
 
 %% ----------------------------------------------------------
-%% handle_call(Request, From, State)
+%% # handle_call/3
 %% ----------------------------------------------------------
 
 handle_call(state, _, State) ->
@@ -199,31 +178,31 @@ handle_call(state, _, State) ->
 handle_call(uptime, _, #state{id = Time} = State) ->
     {reply, diameter_lib:now_diff(Time), State};
 
-handle_call({reg, Pid, Contrib}, _From, State) ->
-    monitor(not ets:member(?TABLE, Pid), Pid),
-    {reply, insert(?REC(Pid, Contrib)), State};
+handle_call({incr, T}, _, State) ->
+    {reply, update_counter(T), State};
 
-handle_call({flush, Contrib}, _From, State) ->
-    {reply, fetch(Contrib), State};
+handle_call({reg, Pid, Ref}, _From, State) ->
+    B = ets:insert_new(?TABLE, {Pid, Ref}),
+    B andalso erlang:monitor(process, Pid),
+    {reply, B, State};
+
+handle_call({flush, Refs}, _From, State) ->
+    {reply, read(Refs, true), State};
 
 handle_call(Req, From, State) ->
     ?UNEXPECTED([Req, From]),
     {reply, nok, State}.
 
 %% ----------------------------------------------------------
-%% handle_cast(Request, State)
+%% # handle_cast/2
 %% ----------------------------------------------------------
 
-handle_cast({incr, Rec}, State) ->
-    update_counter(Rec),
-    {noreply, State};
-
 handle_cast(Msg, State) ->
     ?UNEXPECTED([Msg]),
     {noreply, State}.
 
 %% ----------------------------------------------------------
-%% handle_info(Request, State)
+%% # handle_info/2
 %% ----------------------------------------------------------
 
 handle_info({'DOWN', _MRef, process, Pid, _}, State) ->
@@ -235,91 +214,62 @@ handle_info(Info, State) ->
     {noreply, State}.
 
 %% ----------------------------------------------------------
-%% terminate(Reason, State)
+%% # terminate/2
 %% ----------------------------------------------------------
 
 terminate(_Reason, _State) ->
     ok.
 
 %% ----------------------------------------------------------
-%% code_change(OldVsn, State, Extra)
+%% # code_change/3
 %% ----------------------------------------------------------
 
 code_change(_OldVsn, State, _Extra) ->
     {ok, State}.
 
-%%% ---------------------------------------------------------
-%%% INTERNAL FUNCTIONS
-%%% ---------------------------------------------------------
-
-%% monitor/2
-
-monitor(true, Pid) ->
-    erlang:monitor(process, Pid);
-monitor(false = No, _) ->
-    No.
+%% ===========================================================================
 
 %% down/1
 
 down(Pid) ->
-    L = ets:match_object(?TABLE, ?REC({'_', Pid}, '_')),
-    [?REC(_, Ref) = T] = lookup(Pid),
+    down(lookup(Pid), ets:match_object(?TABLE, {{'_', Pid}, '_'})).
+
+down([{_, Ref} = T], L) ->
     fold(Ref, L),
-    delete_object(T),
+    delete([T|L]);
+down([], L) -> %% flushed
     delete(L).
 
-%% Fold Pid-based entries into Ref-based ones.
+%% Fold pid-based entries into ref-based ones.
 fold(Ref, L) ->
-    lists:foreach(fun(?REC({K, _}, V)) -> update_counter({{K, Ref}, V}) end,
-                  L).
-
-delete(Objs) ->
-    lists:foreach(fun delete_object/1, Objs).
-
-%% fetch/1
-
-fetch(X) ->
-    MatchSpec = [{?REC({'_', '$1'}, '_'),
-                  [?ORCOND([{'==', '$1', {const, T}} || T <- [X | ref(X)]])],
-                  ['$_']}],
-    L = ets:select(?TABLE, MatchSpec),
-    delete(L),
-    D = lists:foldl(fun sum/2, dict:new(), L),
-    dict:to_list(D).
-
-sum({{Ctr, _}, N}, Dict) ->
-    dict:update(Ctr, fun(V) -> V+N end, N, Dict).
-
-ref(Pid)
-  when is_pid(Pid) ->
-    ets:select(?TABLE, [{?REC(Pid, '$1'), [], ['$1']}]);
-ref(_) ->
-    [].
+    lists:foreach(fun({{K, _}, V}) -> update_counter({{K, Ref}, V}) end, L).
 
 %% update_counter/2
 %%
-%% From an arbitrary request process. Cast to the server process to
-%% insert a new element if the counter doesn't exists so that two
-%% processes don't do so simultaneously.
+%% From an arbitrary process. Call to the server process to insert a
+%% new element if the counter doesn't exists so that two processes
+%% don't insert simultaneously.
 
 update_counter(Key, N) ->
     try
         ets:update_counter(?TABLE, Key, N)
     catch
         error: badarg ->
-            cast({incr, ?REC(Key, N)})
+            call({incr, {Key, N}})
     end.
 
 %% update_counter/1
 %%
-%% From the server process.
+%% From the server process, when update_counter/2 failed due to a
+%% non-existent entry.
 
-update_counter(?REC(Key, N) = T) ->
+update_counter({{_Ctr, Ref} = Key, N} = T) ->
     try
         ets:update_counter(?TABLE, Key, N)
     catch
         error: badarg ->
-            insert(T)
+            (not is_pid(Ref) orelse ets:member(?TABLE, Ref))
+                andalso begin insert(T), N end
     end.
 
 insert(T) ->
@@ -328,13 +278,8 @@ insert(T) ->
 lookup(Key) ->
     ets:lookup(?TABLE, Key).
 
-delete_object(T) ->
-    ets:delete_object(?TABLE, T).
-
-%% cast/1
-
-cast(Msg) ->
-    gen_server:cast(?SERVER, Msg).
+delete(Objs) ->
+    lists:foreach(fun({K,_}) -> ets:delete(?TABLE, K) end, Objs).
 
 %% call/1
 
diff --git a/lib/diameter/src/base/diameter_watchdog.erl b/lib/diameter/src/base/diameter_watchdog.erl
index fb22fd8275..d7474e5c56 100644
--- a/lib/diameter/src/base/diameter_watchdog.erl
+++ b/lib/diameter/src/base/diameter_watchdog.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2011. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2012. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -54,7 +54,7 @@
                      %% number of DWAs received during reopen
          %% end PCB
          parent = self() :: pid(),
-         transport       :: pid(),
+         transport       :: pid() | undefined,
          tref :: reference(), %% reference for current watchdog timer
          message_data}).   %% term passed into diameter_service with message
 
@@ -64,6 +64,13 @@
 %% that a failed capabilities exchange produces the desired exit
 %% reason.
 
+-spec start(Type, {RecvData, [Opt], SvcName, #diameter_service{}})
+   -> {reference(), pid()}
+ when Type :: {connect|accept, diameter:transport_ref()},
+      RecvData :: term(),
+      Opt :: diameter:transport_opt(),
+      SvcName :: diameter:service_name().
+
 start({_,_} = Type, T) ->
     Ref = make_ref(),
     {ok, Pid} = diameter_watchdog_sup:start_child({Ref, {Type, self(), T}}),
@@ -102,7 +109,7 @@ i({_, Pid, _} = T) ->  %% from old code
     erlang:monitor(process, Pid),
     make_state(T).
 
-make_state({T, Pid, {ConnT,
+make_state({T, Pid, {RecvData,
                      Opts,
                      SvcName,
                      #diameter_service{applications = Apps,
@@ -116,7 +123,7 @@ make_state({T, Pid, {ConnT,
               tw = proplists:get_value(watchdog_timer,
                                        Opts,
                                        ?DEFAULT_TW_INIT),
-              message_data = {ConnT, SvcName, Apps}}.
+              message_data = {RecvData, SvcName, Apps}}.
 
 %% handle_call/3
 
@@ -134,14 +141,36 @@ handle_info(T, State) ->
     case transition(T, State) of
         ok ->
             {noreply, State};
-        #watchdog{status = X} = S ->
-            ?LOGC(X =/= State#watchdog.status, transition, X),
+        #watchdog{} = S ->
+            event(State, S),
             {noreply, S};
         stop ->
             ?LOG(stop, T),
+            event(State, State#watchdog{status = down}),
             {stop, {shutdown, T}, State}
     end.
 
+event(#watchdog{status = T}, #watchdog{status = T}) ->
+    ok;
+
+event(#watchdog{transport = undefined}, #watchdog{transport = undefined}) ->
+    ok;
+
+event(#watchdog{status = From, transport = F, parent = Pid},
+      #watchdog{status = To, transport = T}) ->
+    E = {tpid(F,T), From, To},
+    notify(Pid, E),
+    ?LOG(transition, {self(), E}).
+
+tpid(_, Pid)
+  when is_pid(Pid) ->
+    Pid;
+tpid(Pid, _) ->
+    Pid.
+
+notify(Pid, E) ->
+    Pid ! {watchdog, self(), E}.
+
 %% terminate/2
 
 terminate(_, _) ->
@@ -251,8 +280,8 @@ transition({'DOWN', _, process, TPid, _},
                      status = initial}) ->
     stop;
 
-transition({'DOWN', _, process, Pid, _},
-           #watchdog{transport = Pid}
+transition({'DOWN', _, process, TPid, _},
+           #watchdog{transport = TPid}
            = S) ->
     failover(S),
     close(S),
@@ -385,7 +414,7 @@ recv(Name, Pkt, S) ->
             rcv(Name, Pkt, S),
             NS
     catch
-        throw: {?MODULE, throwaway, #watchdog{} = NS} ->
+        {?MODULE, throwaway, #watchdog{} = NS} ->
             NS
     end.
 
diff --git a/lib/diameter/src/modules.mk b/lib/diameter/src/modules.mk
index 7a700a6d53..5d3c4157ae 100644
--- a/lib/diameter/src/modules.mk
+++ b/lib/diameter/src/modules.mk
@@ -58,6 +58,7 @@ RT_MODULES = \
 	transport/diameter_tcp_sup \
 	transport/diameter_sctp \
 	transport/diameter_sctp_sup \
+	transport/diameter_transport \
 	transport/diameter_transport_sup
 
 # Handwritten (compile time) modules not included in the app file.
diff --git a/lib/diameter/src/transport/diameter_etcp.erl b/lib/diameter/src/transport/diameter_etcp.erl
index d925d62545..cd62cf34fa 100644
--- a/lib/diameter/src/transport/diameter_etcp.erl
+++ b/lib/diameter/src/transport/diameter_etcp.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2011. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2012. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -36,7 +36,9 @@
          send/2,
          close/1,
          setopts/2,
-         port/1]).
+         sockname/1,
+         peername/1,
+         getstat/1]).
 
 %% child start
 -export([start_link/1]).
@@ -113,10 +115,20 @@ close(Pid) ->
 setopts(_, _) ->
     ok.
 
-%% port/1
+%% sockname/1
 
-port(_) ->
-    3868.  %% We have no local port: fake it.
+sockname(_) ->
+    {error, ?MODULE}.
+
+%% peername/1
+
+peername(_) ->
+    {error, ?MODULE}.
+
+%% getstat/1
+
+getstat(_) ->
+    {error, ?MODULE}.
 
 %% start_link/1
 
diff --git a/lib/diameter/src/transport/diameter_sctp.erl b/lib/diameter/src/transport/diameter_sctp.erl
index 68b0342cd5..79b8b851fb 100644
--- a/lib/diameter/src/transport/diameter_sctp.erl
+++ b/lib/diameter/src/transport/diameter_sctp.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2011. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2012. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -37,12 +37,18 @@
          code_change/3,
          terminate/2]).
 
+-export([info/1]).  %% service_info callback
+
 -export([ports/0,
          ports/1]).
 
 -include_lib("kernel/include/inet_sctp.hrl").
 -include_lib("diameter/include/diameter.hrl").
 
+%% Keys into process dictionary.
+-define(INFO_KEY, info).
+-define(REF_KEY,  ref).
+
 -define(ERROR(T), erlang:error({T, ?MODULE, ?LINE})).
 
 %% The default port for a listener.
@@ -62,6 +68,7 @@
 -record(transport,
         {parent  :: pid(),
          mode :: {accept, pid()}
+               | accept
                | {connect, {list(inet:ip_address()), uint(), list()}}
                         %% {RAs, RP, Errors}
                | connect,
@@ -134,6 +141,24 @@ start_link(T) ->
                         diameter_lib:spawn_opts(server, [])).
 
 %% ---------------------------------------------------------------------------
+%% # info/1
+%% ---------------------------------------------------------------------------
+
+info({gen_sctp, Sock}) ->
+    lists:flatmap(fun(K) -> info(K, Sock) end,
+                  [{socket, sockname},
+                   {peer, peername},
+                   {statistics, getstat}]).
+
+info({K,F}, Sock) ->
+    case inet:F(Sock) of
+        {ok, V} ->
+            [{K,V}];
+        _ ->
+            []
+    end.
+
+%% ---------------------------------------------------------------------------
 %% # init/1
 %% ---------------------------------------------------------------------------
 
@@ -157,7 +182,7 @@ i({connect, Pid, Opts, Addrs, Ref}) ->
     RAs  = [diameter_lib:ipaddr(A) || {raddr, A} <- As],
     [RP] = [P || {rport, P} <- Ps] ++ [P || P <- [?DEFAULT_PORT], [] == Ps],
     {LAs, Sock} = open(Addrs, Rest, 0),
-    putr(ref, Ref),
+    putr(?REF_KEY, Ref),
     proc_lib:init_ack({ok, self(), LAs}),
     erlang:monitor(process, Pid),
     #transport{parent = Pid,
@@ -169,7 +194,7 @@ i({connect, _, _, _} = T) ->  %% from old code
 %% An accepting transport spawned by diameter.
 i({accept, Pid, LPid, Sock, Ref})
   when is_pid(Pid) ->
-    putr(ref, Ref),
+    putr(?REF_KEY, Ref),
     proc_lib:init_ack({ok, self()}),
     erlang:monitor(process, Pid),
     erlang:monitor(process, LPid),
@@ -181,7 +206,7 @@ i({accept, _, _, _} = T) ->  %% from old code
 
 %% An accepting transport spawned at association establishment.
 i({accept, Ref, LPid, Sock, Id}) ->
-    putr(ref, Ref),
+    putr(?REF_KEY, Ref),
     proc_lib:init_ack({ok, self()}),
     MRef = erlang:monitor(process, LPid),
     %% Wait for a signal that the transport has been started before
@@ -325,6 +350,11 @@ terminate(_, #transport{assoc_id = undefined}) ->
     ok;
 
 terminate(_, #transport{socket = Sock,
+                        mode = accept,
+                        assoc_id = Id}) ->
+    close(Sock, Id);
+
+terminate(_, #transport{socket = Sock,
                         mode = {accept, _},
                         assoc_id = Id}) ->
     close(Sock, Id);
@@ -356,13 +386,16 @@ start_timer(S) ->
 
 %% Incoming message from SCTP.
 l({sctp, Sock, _RA, _RP, Data} = Msg, #listener{socket = Sock} = S) ->
-    setopts(Sock),
-    case find(Data, S) of
+    Id = assoc_id(Data),
+
+    try find(Id, Data, S) of
         {TPid, NewS} ->
-            TPid ! Msg,
+            TPid ! {peeloff, peeloff(Sock, Id, TPid), Msg},
             NewS;
         false ->
             S
+    after
+        setopts(Sock)
     end;
 
 %% Transport is asking message to be sent. See send/3 for why the send
@@ -430,15 +463,19 @@ t(T,S) ->
 
 %% transition/2
 
-%% Incoming message.
-transition({sctp, Sock, _RA, _RP, Data}, #transport{socket = Sock,
-                                                    mode = {accept, _}}
-                                         = S) ->
-    recv(Data, S);
+%% Listening process is transfering ownership of an association.
+transition({peeloff, Sock, {sctp, LSock, _RA, _RP, _Data} = Msg},
+           #transport{mode = {accept, _},
+                      socket = LSock}
+           = S) ->
+    transition(Msg, S#transport{socket = Sock});
 
-transition({sctp, Sock, _RA, _RP, Data}, #transport{socket = Sock} = S) ->
+%% Incoming message.
+transition({sctp, _Sock, _RA, _RP, Data}, #transport{socket = Sock} = S) ->
     setopts(Sock),
     recv(Data, S);
+%% Don't match on Sock since in R15B01 it can be the listening socket
+%% in the (peeled-off) accept case, which is likely a bug.
 
 %% Outgoing message.
 transition({diameter, {send, Msg}}, S) ->
@@ -456,13 +493,18 @@ transition({diameter, {close, Pid}}, #transport{parent = Pid}) ->
 transition({diameter, {tls, _Ref, _Type, _Bool}}, _) ->
     stop;
 
+%% Parent process has died.
+transition({'DOWN', _, process, Pid, _}, #transport{parent = Pid}) ->
+    stop;
+
 %% Listener process has died.
 transition({'DOWN', _, process, Pid, _}, #transport{mode = {accept, Pid}}) ->
     stop;
 
-%% Parent process has died.
-transition({'DOWN', _, process, Pid, _}, #transport{parent = Pid}) ->
-    stop;
+%% Ditto but we have ownership of the association. It might be that
+%% we'll go down anyway though.
+transition({'DOWN', _, process, _Pid, _}, #transport{mode = accept}) ->
+    ok;
 
 %% Request for the local port number.
 transition({resolve_port, Pid}, #transport{socket = Sock})
@@ -521,14 +563,6 @@ send(Bin, #transport{streams = {_, OS},
 
 %% send/3
 
-%% Messages have to be sent from the controlling process, which is
-%% probably a bug. Sending from here causes an inet_reply, Sock,
-%% Status} message to be sent to the controlling process while
-%% gen_sctp:send/4 here hangs.
-send(StreamId, Bin, #transport{assoc_id = AId,
-                               mode = {accept, LPid}}) ->
-    LPid ! {send, AId, StreamId, Bin};
-
 send(StreamId, Bin, #transport{socket = Sock,
                                assoc_id = AId}) ->
     send(Sock, AId, StreamId, Bin).
@@ -554,10 +588,9 @@ recv({_, #sctp_assoc_change{state = comm_up,
                 mode = {T, _},
                 socket = Sock}
      = S) ->
-    Ref = getr(ref),
+    Ref = getr(?REF_KEY),
     is_reference(Ref)  %% started in new code
-        andalso
-        (true = diameter_reg:add_new({?MODULE, T, {Ref, {Id, Sock}}})),
+        andalso publish(T, Ref, Id, Sock),
     up(S#transport{assoc_id = Id,
                    streams = {IS, OS}});
 
@@ -599,6 +632,10 @@ recv({_, #sctp_paddr_change{}}, _) ->
 recv({_, #sctp_pdapi_event{}}, _) ->
     ok.
 
+publish(T, Ref, Id, Sock) ->
+    true = diameter_reg:add_new({?MODULE, T, {Ref, {Id, Sock}}}),
+    putr(?INFO_KEY, {gen_sctp, Sock}).  %% for info/1
+
 %% up/1
 
 up(#transport{parent = Pid,
@@ -608,21 +645,15 @@ up(#transport{parent = Pid,
     S#transport{mode = C};
 
 up(#transport{parent = Pid,
-              mode = {accept, _}}
+              mode = {accept = A, _}}
    = S) ->
     diameter_peer:up(Pid),
-    S.
+    S#transport{mode = A}.
 
-%% find/2
-
-find({[#sctp_sndrcvinfo{assoc_id = Id}], _}
-     = Data,
-     #listener{tmap = T}
-     = S) ->
-    f(ets:lookup(T, Id), Data, S);
+%% find/3
 
-find({_, Rec} = Data, #listener{tmap = T} = S) ->
-    f(ets:lookup(T, assoc_id(Rec)), Data, S).
+find(Id, Data, #listener{tmap = T} = S) ->
+    f(ets:lookup(T, Id), Data, S).
 
 %% New association and a transport waiting for one: use it.
 f([],
@@ -663,17 +694,29 @@ f([], _, _) ->
 
 %% assoc_id/1
 
-assoc_id(#sctp_shutdown_event{assoc_id = Id}) ->
+assoc_id({[#sctp_sndrcvinfo{assoc_id = Id}], _}) ->
     Id;
-assoc_id(#sctp_assoc_change{assoc_id = Id}) ->
+assoc_id({_, Rec}) ->
+    id(Rec).
+
+id(#sctp_shutdown_event{assoc_id = Id}) ->
+    Id;
+id(#sctp_assoc_change{assoc_id = Id}) ->
     Id;
-assoc_id(#sctp_sndrcvinfo{assoc_id = Id}) ->
+id(#sctp_sndrcvinfo{assoc_id = Id}) ->
     Id;
-assoc_id(#sctp_paddr_change{assoc_id = Id}) ->
+id(#sctp_paddr_change{assoc_id = Id}) ->
     Id;
-assoc_id(#sctp_adaptation_event{assoc_id = Id}) ->
+id(#sctp_adaptation_event{assoc_id = Id}) ->
     Id.
 
+%% peeloff/3
+
+peeloff(LSock, Id, TPid) ->
+    {ok, Sock} = gen_sctp:peeloff(LSock, Id),
+    ok = gen_sctp:controlling_process(Sock, TPid),
+    Sock.
+
 %% connect/4
 
 connect(_, [], _, Reasons) ->
diff --git a/lib/diameter/src/transport/diameter_tcp.erl b/lib/diameter/src/transport/diameter_tcp.erl
index 78dbda6888..597f2f14d7 100644
--- a/lib/diameter/src/transport/diameter_tcp.erl
+++ b/lib/diameter/src/transport/diameter_tcp.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2011. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2012. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -37,11 +37,17 @@
          code_change/3,
          terminate/2]).
 
+-export([info/1]).  %% service_info callback
+
 -export([ports/0,
          ports/1]).
 
 -include_lib("diameter/include/diameter.hrl").
 
+%% Keys into process dictionary.
+-define(INFO_KEY, info).
+-define(REF_KEY,  ref).
+
 -define(ERROR(T), erlang:error({T, ?MODULE, ?LINE})).
 
 -define(DEFAULT_PORT, 3868).  %% RFC 3588, ch 2.1
@@ -111,6 +117,33 @@ start_link(T) ->
                         diameter_lib:spawn_opts(server, [])).
 
 %% ---------------------------------------------------------------------------
+%% # info/1
+%% ---------------------------------------------------------------------------
+
+info({Mod, Sock}) ->
+    lists:flatmap(fun(K) -> info(Mod, K, Sock) end,
+                  [{socket, fun sockname/2},
+                   {peer, fun peername/2},
+                   {statistics, fun getstat/2}
+                   | ssl_info(Mod, Sock)]).
+
+info(Mod, {K,F}, Sock) ->
+    case F(Mod, Sock) of
+        {ok, V} ->
+            [{K,V}];
+        _ ->
+            []
+    end.
+
+ssl_info(ssl = M, Sock) ->
+    [{M, ssl_info(Sock)}];
+ssl_info(_, _) ->
+    [].
+
+ssl_info(Sock) ->
+    [{peercert, C} || {ok, C} <- [ssl:peercert(Sock)]].
+
+%% ---------------------------------------------------------------------------
 %% # init/1
 %% ---------------------------------------------------------------------------
 
@@ -133,7 +166,7 @@ i({T, Ref, Mod, Pid, Opts, Addrs})
     MPid ! {stop, self()},  %% tell the monitor to die
     M = if SslOpts -> ssl; true -> Mod end,
     setopts(M, Sock),
-    putr(ref, Ref),
+    putr(?REF_KEY, Ref),
     #transport{parent = Pid,
                module = M,
                socket = Sock,
@@ -191,7 +224,7 @@ i(accept = T, Ref, Mod, Pid, Opts, Addrs) ->
     {LAddr, LSock} = listener(Ref, {Mod, Opts, Addrs}),
     proc_lib:init_ack({ok, self(), [LAddr]}),
     Sock = ok(accept(Mod, LSock)),
-    true = diameter_reg:add_new({?MODULE, T, {Ref, Sock}}),
+    publish(Mod, T, Ref, Sock),
     diameter_peer:up(Pid),
     Sock;
 
@@ -202,10 +235,14 @@ i(connect = T, Ref, Mod, Pid, Opts, Addrs) ->
     RPort = get_port(RP),
     proc_lib:init_ack({ok, self(), [LAddr]}),
     Sock = ok(connect(Mod, RAddr, RPort, gen_opts(LAddr, Rest))),
-    true = diameter_reg:add_new({?MODULE, T, {Ref, Sock}}),
+    publish(Mod, T, Ref, Sock),
     diameter_peer:up(Pid, {RAddr, RPort}),
     Sock.
 
+publish(Mod, T, Ref, Sock) ->
+    true = diameter_reg:add_new({?MODULE, T, {Ref, Sock}}),
+    putr(?INFO_KEY, {Mod, Sock}).  %% for info/1
+
 ok({ok, T}) ->
     T;
 ok(No) ->
@@ -521,7 +558,7 @@ tls_handshake(Type, true, #transport{socket = Sock,
                                      ssl = Opts}
                           = S) ->
     {ok, SSock} = tls(Type, Sock, [{cb_info, ?TCP_CB(M)} | Opts]),
-    Ref = getr(ref),
+    Ref = getr(?REF_KEY),
     is_reference(Ref)  %% started in new code
         andalso
         (true = diameter_reg:add_new({?MODULE, Type, {Ref, SSock}})),
@@ -696,12 +733,32 @@ setopts(M, Sock) ->
 
 portnr(gen_tcp, Sock) ->
     inet:port(Sock);
-portnr(ssl, Sock) ->
-    case ssl:sockname(Sock) of
+portnr(M, Sock) ->
+    case M:sockname(Sock) of
         {ok, {_Addr, PortNr}} ->
             {ok, PortNr};
         {error, _} = No ->
             No
-    end;
-portnr(M, Sock) ->
-    M:port(Sock).
+    end.
+
+%% sockname/2
+
+sockname(gen_tcp, Sock) ->
+    inet:sockname(Sock);
+sockname(M, Sock) ->
+    M:sockname(Sock).
+
+%% peername/2
+
+peername(gen_tcp, Sock) ->
+    inet:peername(Sock);
+peername(M, Sock) ->
+    M:peername(Sock).
+
+%% getstat/2
+
+getstat(gen_tcp, Sock) ->
+    inet:getstat(Sock);
+getstat(M, Sock) ->
+    M:getstat(Sock).
+%% Note that ssl:getstat/1 doesn't yet exist in R15B01.
diff --git a/lib/diameter/src/transport/diameter_transport.erl b/lib/diameter/src/transport/diameter_transport.erl
new file mode 100644
index 0000000000..ff4b6bbc6d
--- /dev/null
+++ b/lib/diameter/src/transport/diameter_transport.erl
@@ -0,0 +1,55 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2012. All Rights Reserved.
+%%
+%% The contents of this file are subject to the Erlang Public License,
+%% Version 1.1, (the "License"); you may not use this file except in
+%% compliance with the License. You should have received a copy of the
+%% Erlang Public License along with this software. If not, it can be
+%% retrieved online at http://www.erlang.org/.
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and limitations
+%% under the License.
+%%
+%% %CopyrightEnd%
+%%
+
+-module(diameter_transport).
+
+%%
+%% This module implements a transport start function that
+%% evaluates its config argument.
+%%
+
+%% Transport start functions
+-export([start/3,
+         select/3,
+         eval/3]).
+
+%% start/3
+
+%% Call a start function in this module ...
+start(T, Svc, {F,A}) ->
+    start(T, Svc, {?MODULE, F, [A]});
+
+%% ... or some other.
+start(T, Svc, F) ->
+    diameter_lib:eval([F, T, Svc]).
+
+%% select/3
+%%
+%% A start function that whose config argument is expected to return a
+%% new start function.
+
+select(T, Svc, F) ->
+    start(T, Svc, diameter_lib:eval([F, T, Svc])).
+
+%% eval/3
+%%
+%% A start function that simply evaluates its config argument.
+
+eval(_, _, F) ->
+    diameter_lib:eval(F).