Avaya 8800 Planning And Engineering, Network Design page 290

QoS design guidelines
You can configure Ingress interfaces in one of two ways. In the first type of configuration, the
interface does not classify traffic, but it forwards the traffic based on the packet markings. This mode
of operation is applied to trusted interfaces (core port mode) because the DSCP or 802.1p field is
trusted to be correct, and the edge switch performs the mapping without any classification.
In the second type of configuration, the interface classifies traffic as it enters the port, and marks the
packet for further treatment as it traverses the Ethernet Routing Switch 8800/8600 network. This
mode of operation is applied to untrusted interfaces (access port mode) because the DSCP or
802.1p field is not trusted to be correct.
An internal QoS level is assigned to each packet that enters an Ethernet Routing Switch 8800/8600
port. Once the QoS level is set, the egress queue is determined and the packet is transmitted. The
mapping of QoS levels to queue is a hard-coded 1-to-1 mapping.
Table 32: ADSSC, DSCP, and 802.1p-bit mappings
configuration that a service provider should use for a packet classification scheme. Use the defaults
as a starting point because the actual traffic types and flows are unknown. You can change the
mapping scheme if the default is not optimal. However, Avaya recommends that you do not change
the mappings.
Table 32: ADSSC, DSCP, and 802.1p-bit mappings
ADSSC
Critical
Network
Premium
Platinum
Gold
Silver
Bronze
Standard
Custom/best effort
In this table, ADSSC denotes Avaya Data Solutions Service Class, CS denotes Class Selector, EF
denotes Expedited Forwarding, AF denotes Assured Forwarding, and DE denotes Default
forwarding.
Important:
If you must change the DSCP mappings, ensure that the values are consistent on all other
Ethernet Routing Switches and devices in your network. Inconsistent mappings can result in
unpredictable service.
The Avaya QoS strategy simplifies QoS implementation by providing a mapping of various traffic
types and categories to a Class of Service. These service classes are termed Avaya Data Solutions
Service Classes (ADSSC). The following table provides a summary of the mappings and their
typical traffic types.
June 2016
on page 290 shows the recommended
DSCP
CS7
CS6
EF, CS5
AF4x, CS4
AF3x, CS3
AF2x, CS2
AF1x, CS1
DE, CS0
User Defined
Planning and Engineering — Network Design
Comments on this document? infodev@avaya.com
802.1p
7
7
6
5
4
3
2
0
1
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