Nortel Networks Mediant TP-1610 SIP - Manual (Page 147)

Mediant 2000 SIP User’s Manual 8. Gateway Capabilities Description
Version 4.4 147 July 2005
8.6.4 Relevant Parameters
The following parameters (described in Table 6-5 ) are used to configure the Alternative Routing
mechanism:
• AltRoutingTel2IPEnable
• AltRoutingTel2IPMode
• IPConnQoSMaxAllowedPL
• IPConnQoSMaxAllowedDelay
8.7 Working with Supplementary Services
The Mediant 2000 SIP gateway supports the following supplementary services:
• Hold / Retrieve
• Transfer
• Call Forward (doesn't initiate call forward, only responds to call forward request)
• Call Waiting
Mediant 2000 SIP users are only required to enable the Hold and Transfer features. The call
forward (supporting 30x redirecting responses) and call waiting (receive of 182 response)
features are enabled by default. Note that all call participants must support the specific used
method.
Note: When working with application servers (such as BroadSoft’s BroadWorks) in
client server mode (the application server controls all supplementary services
and keypad features by itself), the gateway’s supplementary services must be
disabled.
8.7.1 Call Hold and Retrieve Features
• The party that initiates the hold is called the holding party, the other party is called the held
party. The Mediant 2000 can't initiate the hold, but it can respond to hold request, and as
such it is a held party.
• After a successful hold, the held party should hear HELD_TONE, defined in gateway's Call
Progress Tones file.
• Retrieve can be performed only by the holding party while the call is held and active.
• After a successful retrieve the voice should be connected again.
• The hold and retrieve functionalities are implemented by Reinvite messages. The IP address
0.0.0.0 as the connection IP address or the string “a=inactive” in the received Reinvite SDP
cause the gateway to enter Hold state and to play held tone (configured in the gateway) to
the PBX/PSTN. If the string “a=recvonly” is received in the SDP message, the gateway stops
sending RTP packets, but continues to listen to the incoming RTP packets. Usually, the
remote party plays, in this scenario, Music on-hold (MOH) and the Mediant 2000 forwards
the MOH to the held party.
8.7.2 Call Transfer
There are two types of call transfers:
• Consultation Transfer
• Blind Transfer
The common way to perform a consultation transfer is as follows: