AudioCodes Mediant 8000, Инструкция по установке, эксплуатации и обслуживанию

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Version 6.6 685 October 2014
Installation & Operation Manual 41. PSTN Gateway and IP-to-IP Applications
Parameter
Name
Type Provisioning
Type
Description
Is Fax Used Enum
NoFax, T38,
G711, FallBack Instant Determines the SIP signaling method used to
establish and convey a fax session after a fax
is detected.
NoFax = No fax negotiation using SIP
signaling (default).
T38 = Initiates T.38 fax relay.
G711 = Initiates fax using the coder G.711 A-
law/m-law with adaptations (see note).
FallBack = Initiates T.38 fax relay. If the T.38
negotiation fails, the gateway re-initiates a fax
session using the coder G.711 A-Law/m-Law
with adaptations (see note).
Notes

Fax adaptations:

-Echo Canceller = On

-Silence Compression = Off

-Echo Canceler Non-Linear Processor
Mode = Off

-Dynamic Jitter Buffer Minimum Delay
= 40

-Dynamic Jitter Buffer Optimization
Factor = 13

If the gateway initiates a fax session using
G.711 , a 'gpmd' attribute is added to the
SDP in the following format:

-For A-law: 'a=gpmd:0
vbd=yes;ecan=on'.

-For m-law: 'a=gpmd:8
vbd=yes;ecan=on'.

When 'IsFaxUsed' is set to any value
besided NoFax the parameter
'FaxTransportMode' is ignored.

When the value of IsFaxUsed is other than
T38, T.38 might still be used without the
control protocol's involvement. To
completely disable T.38, set
FaxTransportMode to a value other than 1.
DJ Buf Min
Delay Integer
0-150 Instant Dynamic jitter buffer minimum delay in msec.
DJ Buf Opt
Factor Integer
0-13 Instant Dynamic Jitter Buffer frame error / delay
optimization factor.
Note: Set to 13 for data (fax & modem) calls.