AudioCodes Mediant 8000, Инструкция по установке, эксплуатации и обслуживанию

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Version 6.6 691 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 1).
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.