The example in Tables 1 and 2 is another scenario where fax support is required. In this example we assume that Carrier 1 can support G.729A encoding as well as G.711. In the packet-to-packet control fields of the two PSPs we have selected "conditional" transcoding with no explicit conditions selected. This causes
Table 1: G.729 Pass Through with G.711 to T.38 Fallback for Fax PSPs
Configuration | Value | |
---|---|---|
Carrier 1 Media G.711 (or G.729A) w/ Fax | Carrier 2 Media G.729A w/Fax | |
PSP | PSP-Carrier1 | PSP-to-Peer |
Silence Factor | 40 | 40 |
Voice Initial Playout Buffer | 10 | 10 |
TOS | 0 | 184 |
Data Initial Playout Buffer | 50 | 50 |
Codec Entry 1 | G711-DEFAULT | G729A-DEFAULT - FaxViaT38 |
Codec Entry 2 | G729A-DEFAULT - FaxViaG711 | <none> |
Codec Entry 3 | <none> | <none> |
Codec Entry 4 | <none> | <none> |
AAL Payload Size | 47 | 47 |
T.38 No. Redundant Packets | 1 | 1 |
T.38 Low Speed No. Redundant Packets | 1 | 1 |
T.38 Max Bit Rate | 14.4 | 14.4 |
Data Rate Mgt Type | Type 2 | Type 2 |
Honor Remote Precedence | Disabled | Disabled |
P2P Transcode | Conditional | Conditional |
Conditions | <none selected> | <none selected> |
Codecs Allowed This Leg | G.711A, G.711U | G.729, T.38 |
Codecs Allowed Other Leg | <none selected> | <none selected> |
RTCP | <not selected> | <not selected> |
Silence Insertion Descriptor | Take defaults | Take defaults |
Digit Detect Send Enabled | <not selected> | <not selected> |
Table 2: G.729 Pass-Thru with G.711 to T.38 Fallback for Fax Codec Entries
Configuration | Value | ||
---|---|---|---|
G711-DEFAULT | G729A-DEFAULT FaxViaG711 | G729A-DEFAULT FaxViaT38 | |
Audio Encoding | G.711 | G.729A | G.729A |
Fax Tone Treatment | <none> | Fallback to G.711 | Fax Relay |
Packet Size | 10 ms | 10 ms | 10 ms |
Fax Treatment Failure Handling | Continue | Continue | Continue |
G.711 Law | Law from other leg | N/A | N/A |
Modem Tone Treatment | None | None | None |
Modem Treatment Failure Handling | Continue | Continue | Continue |
DTMF Relay | None | None | None |