Siemens 420 S, 410 S manual Music on Hold MOH, SdpLineNumiteratorinit&iterator

Music on Hold (MOH)

Execution of Call Pickup

8 Music on Hold (MOH)

The RFC 3261 offers several options for indicating " On Hold". In case of an optiPoint tele- phone, a method "INACTIVE" is added to the session description if the other party is put on hold. Asterisk, however, only recognizes "SENDONLY".

There is a workaround to make sure that Asterisk plays the MOH (Music on Hold) in spite of that. You have to modify the file chan_sip.c which by default is stored in the folder /usr/src/as- terisk/channels.

In line 3552 the RTP MAP is assigned.

This is the original source code:

sdpLineNum_iterator_init(&iterator);

while ((a = get_sdp_iterate(&iterator, req, "a"))[0] != '\0') { char* mimeSubtype = ast_strdupa(a); /* ensures we have enough

space */

if (!strcasecmp(a, "sendonly")) { sendonly=1;

continue;

}

if (!strcasecmp(a, "sendrecv")) { sendonly=0;

}

if (sscanf(a, "rtpmap: %u %[^/]/", &codec, mimeSubtype) != 2) continue;

if (debug)

ast_verbose("Found description format %s\n", mimeSubtype);

/* Note: should really look at the 'freq' and '#chans' params

too */

ast_rtp_set_rtpmap_type(p->rtp, codec, "audio", mimeSubtype);

if (p->vrtp) ast_rtp_set_rtpmap_type(p->vrtp, codec, "video",

mimeSubtype);

}

For evaluating the INACTIVE of the optiPoint telephones, the If loop has to be adjusted in a cer- tain way so that the INACTIVE is interpreted as SENDONLY.

24	30. June 2006
	optiPoint 410/420 - Using with Asterisk, Configuration Guide