<?xml version="1.0" encoding="latin1" ?> <!DOCTYPE erlref SYSTEM "erlref.dtd" [ <!ENTITY gen_sctp '<seealso marker="kernel:gen_sctp">gen_sctp(3)</seealso>'> <!ENTITY gen_sctp_open1 '<seealso marker="kernel:gen_sctp#open-1">gen_sctp:open/1</seealso>'> <!ENTITY ip_address '<seealso marker="kernel:inet#type-ip_address">inet:ip_address()</seealso>'> <!ENTITY inet '<seealso marker="kernel:inet">inet(3)</seealso>'> <!ENTITY % also SYSTEM "seealso.ent" > <!ENTITY % here SYSTEM "seehere.ent" > %also; %here; ]> <erlref> <header> <copyright> <year>2011</year><year>2013</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> 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. </legalnotice> <title>diameter_sctp(3)</title> <prepared>Anders Svensson</prepared> <responsible></responsible> <docno></docno> <approved></approved> <checked></checked> <date></date> <rev></rev> <file>diameter_sctp.xml</file> </header> <module>diameter_sctp</module> <modulesummary>Diameter transport over SCTP.</modulesummary> <description> <p> This module implements diameter transport over SCTP using &gen_sctp;. It can be specified as the value of a transport_module option to &mod_add_transport; and implements the behaviour documented in &man_transport;.</p> <marker id="start"/> </description> <!-- ===================================================================== --> <funcs> <func> <name>start({Type, Ref}, Svc, [Opt]) -> {ok, Pid, [LAddr]} | {error, Reason}</name> <fsummary>Start a transport process.</fsummary> <type> <v>Type = connect | accept</v> <v>Ref = &mod_transport_ref;</v> <v>Svc = #diameter_service{}</v> <v>Opt = OwnOpt | SctpOpt</v> <v>Pid = pid()</v> <v>LAddr = &ip_address;</v> <v>Reason = term()</v> <v>OwnOpt = {raddr, &ip_address;} | {rport, integer()} | {accept, Match}</v> <v>SctpOpt = term()</v> <v>Match = &ip_address; | string() | [Match]</v> </type> <desc> <p> The start function required by &man_transport;.</p> <p> Options <c>raddr</c> and <c>rport</c> specify the remote address and port for a connecting transport and not valid for a listening transport: the former is required while latter defaults to 3868 if unspecified. Multiple <c>raddr</c> options can be specified, in which case the connecting transport in question attempts each in sequence until an association is established.</p> <p> Option <c>accept</c> specifies remote addresses for a listening transport and is not valid for a connecting transport. If specified, a remote address that does not match one of the specified addresses causes the association to be aborted. Multiple <c>accept</c> options can be specified. A string-valued <c>Match</c> that does not parse as an address is interpreted as a regular expression.</p> <p> Remaining options are any accepted by &gen_sctp_open1;, with the exception of options <c>mode</c>, <c>binary</c>, <c>list</c>, <c>active</c> and <c>sctp_events</c>. Note that options <c>ip</c> and <c>port</c> specify the local address and port respectively.</p> <p> Multiple <c>ip</c> options can be specified for a multihomed peer. If none are specified then the values of <c>Host-IP-Address</c> in the <c>#diameter_service{}</c> record are used. (In particular, one of these must be specified.) Option <c>port</c> defaults to 3868 for a listening transport and 0 for a connecting transport.</p> <warning> <p> An insufficiently large receive buffer may result in a peer having to resend incoming messages: set the &inet; option <c>recbuf</c> to increase the buffer size.</p> <p> An insufficiently large send buffer may result in outgoing messages being discarded: set the &inet; option <c>sndbuf</c> to increase the buffer size.</p> </warning> <p> diameter_sctp uses the <c>transport_data</c> field of the <c>#diameter_packet{}</c> record to communicate the stream on which an inbound message has been received, or on which an outbound message should be sent: the value will be of the form <c>{stream, Id}</c> on an inbound message passed to a &app_handle_request; or &app_handle_answer; callback. For an outbound message, either <c>undefined</c> (explicitly or by receiving the outbound message as a <c>binary()</c>) or a tuple should be set in the return value of &app_handle_request; (typically by retaining the value passed into this function) or &app_prepare_request;. The value <c>undefined</c> uses a "next outbound stream" id and increments this modulo the total number outbound streams. That is, successive values of <c>undefined</c> cycle through all outbound streams.</p> <!-- TODO: Some way of getting at the number of available outbound --> <!-- streams. --> </desc> </func> </funcs> <!-- ===================================================================== --> <!-- ===================================================================== --> <section> <title>SEE ALSO</title> <p> &man_main;, &man_transport;, &gen_sctp;, &inet;</p> </section> </erlref>