Avaya P333R, User Manual

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Chapter 1 Overview
Avaya P333R User’s Guide
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A P333R unit configured to back up another unit monitors the other’s status by
polling it at configured intervals, and automatically detects when the other fails and
when it becomes functional again. When detecting a failure, the backup P333R
sends a gratuitous ARP message that causes all stations to send their IP traffic to the
backup P333R MAC address instead of the failed unit MAC address. As long as it is
an active backup resulting from the failure of the main unit, the backup P333R
answers ARP requests for the main unit, providing its own MAC address.
OSPF Load Balancing
The P333R supports load balancing in Layer 3 by using OSPF Equal Cost Multipath
(ECM) and static routes multipath. OSPF and static multipath balances Layer 3 load
forwarding by splitting traffic into several possible equal-cost paths, thus freeing
additional bandwidth for traffic.
Policy – Quality of Service (QoS)
The P333R supports QoS by using multiple priority levels and IEEE 802.1p priority
tagging to ensure that data and voice receive the necessary levels of service.
The Avaya P333R can enforce policy on routed packets (per packet), according to
four criteria:
•
The IEEE 802.1p priority tag in the incoming packet.
• The Diff-Serv byte (TOS field) in the IP header of the incoming packet.
• Matching the packet’s source or destination IP address to the configured
priority policy.
• Whether the packet source or destination TCP/UDP port number falls within a
pre-defined range.
Since the P333R is a multilayer switch, it can enforce centralized network policies
using Avaya’s RealNet Rules central policy management application.
Policy – Access Control
The P333R supports Access Control policy. The P333R uses policy lists containing
both Access Control rules and QoS rules. The policy lists are ordered by rule
indexing. Access Control rules define how the P333R should handle routed packets.
There are three possible ways to handle such packets:
•
Forward the packet (Permit operation)
• Discard the packet (Deny operation)
• Discard the packet and notify the management station (Deny and Notify)
The Avaya P333R can enforce Access Control policy on each routed packet,
according to the following criteria:
•
Matching the packet's source or destination IP address to the configured Access
Control policy.