AudioCodes Mediapack mp-11x, Руководство пользователя

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Version 5.2 119 August 2007
SIP User's Manual 5. Web-based Management
Table 5-15: Keypad Features Parameters
Parameter Description
Deactivate
[KeyHotLineDeact]
Keypad sequence that deactivates the delayed hotline option.
After the sequence is pressed a confirmation tone is heard.
Note:
Applicable only to FXS endpoints.
Transfer
Blind
[KeyBlindTransfer]
Keypad sequence that activates the blind transfer option. After this
sequence is dialed, the current call is put on hold, a dial tone is played to
the phone, and then phone number collection starts. After the phone
number is collected, it's sent to the transferee in a SIP REFER request
(without a Replaces header). The call is then terminated and a confirmation
tone is played to the phone. If the phone number collection fails due to a
mismatch, reorder tone is played to the phone.
Note:
Applicable only to FXS endpoints.
Call Waiting
Note that the call waiting can be viewed in the Call Waiting table (refer to 'Call Waiting' on page 359 ).
Activate
[KeyCallWaiting]
Keypad sequence that activates the Call Waiting option. After the sequence
is pressed a confirmation tone is heard.
Deactivate
[KeyCallWaitingDeact]
Keypad sequence that deactivates the Call Waiting option. After the
sequence is pressed a confirmation tone is heard.
5.5.2.5 Stand-Alone Survivability
The
Stand-Alone Survivability
option is used to configure the SAS 'survivability' feature
for Small Medium Enterprises (SME) that implement IP Centrex services. In such
environments, the enterprise's incoming and outgoing telephone calls (external and
internal) are controlled by the IP Centrex, which communicates with the enterprise through
the WAN interface. However, to ensure call service survivability in the face of a WAN / IP
or IP Centrex failure, a PSTN backup connection is provided.
This solution is provided by the gateway's integrated SAS (back-to-back User Agent) and a
dedicated connection to the PSTN network. The SAS operates in one of two modes:
„
Normal Mode:
Initially, the SAS acts as a registrar so that every IP phone or
residential gateway (CPE) within the SME registers to it, while it passes all registration
requests to the IP Centrex. In Normal mode, the SAS functions as a statefull proxy,
passing all SIP requests received from the enterprise to the IP Centrex, and vice
versa. In parallel, the SAS continuously maintains a ‘Keep-Alive’ handshake with the
IP Centrex proxy, using SIP OPTIONS or re-INVITE messages.
„
Emergency Mode:
The SAS switches to Emergency mode if it determines (from the
‘Keepalive’ responses) that connection with the IP Centrex is lost. This can occur due
to IP Centrex server failure or WAN problems. In Emergency mode, when the IP
Centrex server is down, the SAS controls all internal calls within the enterprise. In the
case of outgoing calls, the SAS forwards them to the local VoIP gateway (this can be
an analog FXO to PSTN or a gateway with digital E1/T1 trunk(s) to PSTN). In this
way, the enterprise preserves its capability for outgoing calls.
When Emergency mode is active, the SAS continuously attempts to access the IP
Centrex proxy using the regular ‘Keepalive’ method. After the connection is re-