diameter_sctp(3erl) Erlang Module Definition diameter_sctp(3erl)
NAME
diameter_sctp - Diameter transport over SCTP.
DESCRIPTION
This module implements diameter transport over SCTP using
gen_sctp(3erl). It can be specified as the value of a transport_module
option to diameter:add_transport/2 and implements the behaviour docu-
mented in diameter_transport(3erl).
EXPORTS
start({Type, Ref}, Svc, [Opt]) -> {ok, Pid, [LAddr]} | {error, Reason}
Types:
Type = connect | accept
Ref = diameter:transport_ref()
Svc = #diameter_service{}
Opt = OwnOpt | SctpOpt
Pid = pid()
LAddr = inet:ip_address()
Reason = term()
OwnOpt = {raddr, inet:ip_address()} | {rport, integer()} |
{accept, Match} | {unordered, boolean() | pos_integer()} |
{packet, boolean() | raw} | {message_cb, diameter:eval()} |
{sender, boolean()}
SctpOpt = term()
Match = inet:ip_address() | string() | [Match]
The start function required by diameter_transport(3erl).
Options raddr and rport 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 unspeci-
fied. Multiple raddr options can be specified, in which case the
connecting transport in question attempts each in sequence until
an association is established.
Option accept specifies remote addresses for a listening trans-
port and is not valid for a connecting transport. If specified,
a remote address that does not match one of the specified ad-
dresses causes the association to be aborted. Multiple accept
options can be specified. A string-valued Match that does not
parse as an address is interpreted as a regular expression.
Option unordered specifies whether or not to use unordered de-
livery, integer N being equivalent to N =< OS, where OS is the
number of outbound streams negotiated on the association in
question. Regardless of configuration, sending is ordered on
stream 0 until reception of a second incoming message, to ensure
that a peer receives capabilities exchange messages before any
other. Defaults to false.
Option packet determines how/if an incoming message is packaged
into a diameter_packet record. If false then messages are re-
ceived as binary(). If true then as a record with the binary()
message in the bin field and a {stream, Id} tuple in the trans-
port_data field, where Id is the identifier of the inbound
stream the message was received on. If raw then as a record with
the received ancillary sctp_sndrcvinfo record in the trans-
port_data field. Defaults to true.
Options message_cb and sender have semantics identical to those
documented in diameter_tcp(3erl), but with the message argument
to a recv callback being as directed by the packet option.
An {outstream, Id} tuple in the transport_data field of a outgo-
ing diameter_packet record sets the outbound stream on which the
message is sent, modulo the negotiated number of outbound
streams. Any other value causes successive such sends to cycle
though all outbound streams.
Remaining options are any accepted by gen_sctp:open/1, with the
exception of options mode, binary, list, active and sctp_events.
Note that options ip and port specify the local address and port
respectively.
Multiple ip options can be specified for a multihomed peer. If
none are specified then the values of Host-IP-Address in the di-
ameter_service record are used. Option port defaults to 3868 for
a listening transport and 0 for a connecting transport.
Warning:
An small receive buffer may result in a peer having to resend
incoming messages: set the inet(3erl) option recbuf to increase
the buffer size.
An small send buffer may result in outgoing messages being dis-
carded: set the inet(3erl) option sndbuf to increase the buffer
size.
SEE ALSO
diameter(3erl), diameter_transport(3erl), gen_sctp(3erl), inet(3erl)
Ericsson AB diameter 2.2.3 diameter_sctp(3erl)