4 files changed, 9 insertions, 8 deletions
diff --git a/lib/ssl/src/dtls_connection.erl b/lib/ssl/src/dtls_connection.erl
index 78662e0ea2..153d3fef48 100644
--- a/lib/ssl/src/dtls_connection.erl
+++ b/lib/ssl/src/dtls_connection.erl
@@ -145,7 +145,7 @@ init([Role, Host, Port, Socket, {SSLOpts0, _} = Options,  User, CbInfo]) ->
     process_flag(trap_exit, true),
     State0 =  initial_state(Role, Host, Port, Socket, Options, User, CbInfo),
     Handshake = ssl_handshake:init_handshake_history(),
-    TimeStamp = calendar:datetime_to_gregorian_seconds({date(), time()}),
+    TimeStamp = erlang:monotonic_time(),
     try ssl_config:init(SSLOpts0, Role) of
 	{ok, Ref, CertDbHandle, FileRefHandle, CacheHandle,  CRLDbInfo, OwnCert, Key, DHParams} ->
 	    Session = State0#state.session,
diff --git a/lib/ssl/src/ssl_connection.erl b/lib/ssl/src/ssl_connection.erl
index 12a56df69f..241871dc38 100644
--- a/lib/ssl/src/ssl_connection.erl
+++ b/lib/ssl/src/ssl_connection.erl
@@ -974,7 +974,7 @@ ssl_config(Opts, Role, State) ->
     {ok, Ref, CertDbHandle, FileRefHandle, CacheHandle, CRLDbInfo, OwnCert, Key, DHParams} = 
 	ssl_config:init(Opts, Role), 
     Handshake = ssl_handshake:init_handshake_history(),
-    TimeStamp = calendar:datetime_to_gregorian_seconds({date(), time()}),
+    TimeStamp = erlang:monotonic_time(),
     Session = State#state.session,
     State#state{tls_handshake_history = Handshake,
 		session = Session#session{own_certificate = OwnCert,
diff --git a/lib/ssl/src/ssl_manager.erl b/lib/ssl/src/ssl_manager.erl
index cc15678f23..9e535104f7 100644
--- a/lib/ssl/src/ssl_manager.erl
+++ b/lib/ssl/src/ssl_manager.erl
@@ -320,7 +320,7 @@ handle_call({unconditionally_clear_pem_cache, _},_, #state{certificate_db = [_,_
 handle_cast({register_session, Host, Port, Session}, 
 	    #state{session_cache_client = Cache,
 		   session_cache_cb = CacheCb} = State) ->
-    TimeStamp = calendar:datetime_to_gregorian_seconds({date(), time()}),
+    TimeStamp = erlang:monotonic_time(),
     NewSession = Session#session{time_stamp = TimeStamp},
     
     case CacheCb:select_session(Cache, {Host, Port}) of
@@ -335,7 +335,7 @@ handle_cast({register_session, Host, Port, Session},
 handle_cast({register_session, Port, Session},  
 	    #state{session_cache_server = Cache,
 		   session_cache_cb = CacheCb} = State) ->    
-    TimeStamp = calendar:datetime_to_gregorian_seconds({date(), time()}),
+    TimeStamp =  erlang:monotonic_time(),
     NewSession = Session#session{time_stamp = TimeStamp},
     CacheCb:update(Cache, {Port, NewSession#session.session_id}, NewSession),
     {noreply, State};
@@ -502,7 +502,7 @@ invalidate_session(Cache, CacheCb, Key, Session, #state{last_delay_timer = LastT
 	#session{is_resumable = new} ->
 	    CacheCb:delete(Cache, Key),
 	    {noreply, State};
-	_ ->
+	_ -> 
 	    %% When a registered session is invalidated we need to wait a while before deleting
 	    %% it as there might be pending connections that rightfully needs to look
 	    %% up the session data but new connections should not get to use this session.
@@ -530,7 +530,7 @@ new_id(Port, Tries, Cache, CacheCb) ->
     Id = crypto:rand_bytes(?NUM_OF_SESSION_ID_BYTES),
     case CacheCb:lookup(Cache, {Port, Id}) of
 	undefined ->
-	    Now =  calendar:datetime_to_gregorian_seconds({date(), time()}),
+	    Now = erlang:monotonic_time(),
 	    %% New sessions can not be set to resumable
 	    %% until handshake is compleate and the
 	    %% other session values are set.
diff --git a/lib/ssl/src/ssl_session.erl b/lib/ssl/src/ssl_session.erl
index 1849a05314..0ee8a096e9 100644
--- a/lib/ssl/src/ssl_session.erl
+++ b/lib/ssl/src/ssl_session.erl
@@ -66,8 +66,9 @@ client_id(ClientInfo, Cache, CacheCb, OwnCert) ->
 %% Description: Check that the session has not expired
 %%--------------------------------------------------------------------
 valid_session(#session{time_stamp = TimeStamp}, LifeTime) ->
-    Now =  calendar:datetime_to_gregorian_seconds({date(), time()}),
-    Now - TimeStamp < LifeTime.
+    Now = erlang:monotonic_time(),
+    Lived = erlang:convert_time_unit(Now-TimeStamp, native, seconds),
+    Lived < LifeTime.
 
 server_id(Port, <<>>, _SslOpts, _Cert, _, _) ->
     {ssl_manager:new_session_id(Port), undefined};