Digits Collection Support - AudioCodes Mediant 1000 User Manual

User's Manual
v=0
c= IN IP4 $
m=audio $ RTP/AVP 0
m=image $ udptl t38
The first three lines describe the voice stream, and can differ according to the user's
requirements. Attributes to the voice ('a' lines) should be added after the first 'm' line. The
'm=image' line, however, is mandatory, and should appear in the identical format to the
above.
The Mediant 1000 returns a fully specified line with the local port used for the T.38.
Fax redundancy can be requested by including the following attribute line after the
'm=image' line:
a=T38FaxUdpEC:T38UdpRedundancy
This parameter is only applicable for non-V21 packets. For V21 packets, the redundancy is
hard coded 4.
Two modes of fax support are available. The modes are chosen by the value of bit 2 (value
4) of the MEGACO profiling parameter MGCPCompatibilityProfile. If this bit is not set, the
Mediant 1000 uses a positive negotiation:
If the 'm=image' line is not received both in local AND in remote descriptors, the
Mediant 1000 works with the defaults defined in the Mediant 1000. For example, if the
Mediant 1000 is configured to work with T.38 (default setting) and the 'm=image' line is
received in the local description only, the Mediant 1000 still works with T.38.
If the fax redundancy attribute line does not appear both in local and remote
descriptors, the Mediant 1000 uses the default value.
However, if bit 2 is set, the negotiation rules are as follows:
If the 'm=image' line is not received both in local AND remote descriptors, T.38 is NOT
used. In this case, if the local SDP "m=audio" line contains the G.711 coder, the fax
and modem mode is Bypass (VBD), and the G.711 payload type is used for the fax.
The modem payload type is still according to the ini file. If the G.711 coder is not
offered in the local SDP, the Fax and modem Transport Type is Transparent.
If the fax redundancy attribute line does not appear both in local and remote
descriptors, redundancy for non-V21 packets is NOT used.

7.2.2.13 Digits Collection Support

The following methods for digit collection are supported:
One by one collection using the single events in the 'dd' package (e.g., dd/d3).
Collection according to digit map. This includes the basic collection 'dd/ce' event
defined in the basic package and the 'xdd/xce' and 'edd/mce', both defined it
H.248.16. The maximal pattern length is 150 bytes, and the maximal collected number
is 30 digits. For the extended digit collection, the buffering of type ahead digits
continues up to the limit of 30 digits. New digits after that are lost.
Version 4.6 89
7. Standard Control Protocols
August 2005