Administrator Guide

Layer 2 Switching Commands 680
Diffserv
Standard IP-based networks are designed to provide “best effort” data delivery
service. Best effort service implies that the network delivers the data in a
timely fashion, although there is no guarantee that it will meet the latency or
bandwidth requirements. During times of congestion, packets may be
delayed, sent sporadically, or dropped. For typical Internet applications, such
as email and file transfer, a slight degradation in service is acceptable and in
many cases unnoticeable. Conversely, any
degradation of service has undesirable effects on applications with strict
timing requirements, such as voice or multimedia.
Diffserv allows the network operator to classify and apply a distinguished
service to traffic based on a number of criteria. The distinguished service can
meter traffic and apply per hop behavior based upon the bandwidth
utilization and burstiness of traffic. In addition, preferential drop
characteristics can be configured in support of an assured forwarding
capability such that TCP clients are informed if they exceed the switch
buffering limits.
Commands in this Section
This section explains the following commands:
assign-queue mark ip-dscp match source-
address mac
show class-map
class mark ip-precedence match srcip show classofservice
dot1p-mapping
class-map match class-map match srcip6 show classofservice ip-
dscp-mapping
class-map rename match cos match srcl4port show classofservice
trust
classofservice
dot1p-mapping
match destination-
address mac
match vlan show diffserv
classofservice ip-
dscp-mapping
match dstip mirror show diffserv service
interface
2CSNXXX_SWUM204.book Page 680 Monday, January 25, 2016 1:25 PM