Avaya Voice Priority Processor Overview; Multiple Avaya Voice Priority Processors - Avaya AVPP Installation Manual

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2. Avaya Voice Priority Processor Overview

Avaya Voice Priority Processor (AVPP) utilizes SpectraLink Voice Priority (SVP) as the
quality of service (QoS) mechanism that is implemented in the Wireless Telephone and
access point (AP) to enhance voice quality over the wireless network. SVP gives
preference to voice packets over data packets on the wireless medium, increasing the
probability that all voice packets are transmitted efficiently and with minimum delay.
SVP is fully compliant with the IEEE 802.11 and 802.11b standards.
The AVPP is an Ethernet LAN device that works with the AP to provide QoS on the
wireless LAN. Voice packets to and from the Avaya Wireless Telephones are intercepted
by the AVPP and encapsulated for prioritization as they are routed to and from an IP
telephony server or gateway.
SVP is required for QoS because the current IEEE 802.11b wireless LAN standard
provides no mechanism for differentiating audio packets from data packets. This standard
is undergoing revision to version 802.11e to provide functionality similar to SVP in an
industry standard thus ensuring high-quality voice in a mixed client environment. Once
802.11e is ratified, Avaya and its 802.11 technology partners will adopt the new
specification.
IP multicast addresses are used by the Avaya 3626 Wireless Telephone.
This requires that multicasting be enabled on the subnet used for the
Wireless Telephones, AVPP, and Telephony Gateways.
Routers are typically configured with filters to prevent multicast traffic
from flowing outside of specific domains. The wireless LAN can be
placed on a separate VLAN or subnet to reduce the effects of broadcast
and multicast traffic from devices in other network segments.
2.1

Multiple Avaya Voice Priority Processors

Multiple AVPP environments are those that have more than one AVPP in the same
subnet in order to accommodate larger systems and higher call capacity.
In a system comprised of multiple Avaya Voice Priority Processors using an IP protocol,
a master AVPP must be identified. The master SVP Server must have a static IP address.
The Wireless Telephones and the other AVPP's locate the master by using a static IP
address, DHCP, or DNS. The loss of a non-master AVPP does not significantly affect the
operation of the remaining Avaya Voice Priority Processors. However, the loss of the
master AVPP results in a loss of all communication between all of the Avaya Voice
Priority Processors. This also means that the loss of the master AVPP results in the loss
of all active calls and Wireless Telephones cannot check-in until communication with the
master is reestablished.
In a Gateway system using multiple Avaya Voice Priority Processors, there is no
"master" server.
555-301-102, Issue 4, May 2004
Installation
Avaya Voice Priority Processor
Page 7