Avaya X330WAN - Manual (Page 70)

Chapter 4 Operational Concepts and Configuration Examples
48 Avaya X330WAN User’s Guide
Note: You must configure the Primary VC before associating a DLCI Map Class to
the priority-DLCI group VCs. Removing the Primary VC after associating a DLCI
Map Class to the priority-DLCI group VCs, removes their Map Class configuration.
Enable Traffic Shaping on a Frame Relay interface using the frame-relay
traffic-shaping command. After you enable Traffic Shaping, a default Map Class
is applied to all PVC currently configured. In this default Map Class, the BE = 0,
causing all traffic above the BC to be dropped.
Priority Queuing
Priority Queuing is designed to give all mission-critical programs higher priority
than less critical traffic. Traffic is queued as high, normal, medium, or low. Using
Priority Queuing, all high-priority traffic is serviced first, then normal, etc.
The Frame Relay ingress queuing mechanism functions the same as on PPP
interfaces, described in "QoS Implementation for PPP Encapsulation" on page 55.
The Frame Relay egress queuing mechanism also functions the same as on PPP
interfaces, serving all PVCs configured on the interface, with an additional
user-configurable DE buffer. The DE buffer contains all traffic marked as Discard
Eligible, and has the lowest priority.
When using VoIP, X330WAN enables a distinction within the High-priority queue
between priorities 6 and 7. X330WAN uses priority 6 for the voice-bearer traffic, and
priority 7 for the voice-controller traffic. These two priorities are served on a
Round-Robin basis. Within the High-priority queue the priority 6 (voice-bearer)
capacity is a maximum of 25% the size of the priority 7 (voice-controller) capacity to
reduce the delay of voice flow. The priority 6-7 distinction exists in Data mode as
well, where the queue is divided equally between both capacities.
Policy
X330WAN Policy concept allows you to:
•
Change the packet’s Layer 2 Priority, thereby affecting the traffic’s QoS.
• Perform the “drop”, “drop and notify”, and “permit” Access Control actions.
• Change the DSCP value in the IP header of the packet (DSCP coloring).
A Policy list contains:
•
A set of classification rules based on a source IP, destination IP, source port,
destination port, protocol, and TCP Established bit. The IP addresses can
include wildcards.
• A set of DSCP-802.1p mappings.
• A list of possible Policy actions arranged in a Composite Operations Table.