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Call Detail Recording
R2-MFC (Multifrequency-Signaling) trunks
Multi-location functionality is subject to the following limitations:
25 Countries
R2-MFC: 8 signaling sets
Additional Tone Generators (TN 2182 in Port Networks, built-in tone generators in Media
Gateways) are required to support country-specific tones
No per-country alarms or traffic reports are available
LSPs must be set to the same time zone as the server
This feature is intended for IP-remoted gateways, not DS1-remoted Port Networks.
Modem/Fax/TTY over IP
In the past, many organizations have experienced problems transporting modem, fax, and TTY
tones over an IP Telephony network, regardless of vendor. Modems, faxes, and TTYs are very
sensitive to latency and jitter, and do not tolerate distortion induced through compression,
expansion, and transcoding. In order to overcome these difficulties, Avaya has enhanced its
modem, fax, and TTY-over-IP support in release 2.2.
There are two enhanced modes for supporting Modem-over-IP (MoIP): pass-through and relay.
Pass-through is essentially a best-effort transmission, and works by forcing the use of the G.711
(uncompressed) codec for the call. Re-transmission is governed by the application.
Pass-through mode is suited to LAN environments where both ends of a call are synchronized
using a common clock source. Relay, on the other hand, uses redundant packet transmission to
protect against packet loss. Because relay mode does not force the use of G.711, it requires
less bandwidth than pass-through, however requires more DSP resources. Relay is more
effective than pass-through across a WAN.
Avaya's TTYoIP support works by identifying TTY Baudot tones at the near-end Media
Processor, removing them from the voice path, and transporting them across the network in
RFC 2833 messages. The far-end Media Processor receives the RFC 2833 messages and
regenerates them for the far-end station. This feature is enabled by default on IP trunks and
inter-gateway calls, and is capable of toggling between text and voice modes.
Avaya's support for modem, fax, and TTY over IP can be summarized as follows:
TTY over IP continues to be supported
Modem Pass-through is supported between Avaya gateways
Modem Relay at 9.6K is supported between Avaya gateways
Avaya supports sending multiple instances of the same packet
Redundant transmission mitigates the effects of packet loss, but requires additional bandwidth.
Call Processing
Issue 3.4.1 June 2005
97
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