Extreme Networks BlackDiamond 6800 Installation And User Manual page 77

One potential use of the DSCP mapping capability is to reconcile varying DiffServ
policies at the boundary between autonomous systems, such as at the boundary
between two ISPs. The availability of different tables for the congested and
noncongested states is useful in marking operations that increase the probability of
packets being dropped during times of congestion, as discussed in the DiffServ Assured
Forwarding RFC (RFC 2597).
This command applies only to ATM ports with IP frames that are encapsulated
for bridged or routed protocols. You should also be aware that DSCP mapping is
performed even when the
port.
To configure the mapping between an input DSCP and an associated output DSCP, use
the following command:
config diffserv dscp-mapping <input_codepoint>/<output_codepoint>
ports <portlist> {egress {no-congestion | congestion} | ingress}
where:
input_codepoint
output_codepoint
egress
no-congestion
congestion
ingress
If you omit the
mapping to the tables for both states.
If you omit the
the egress direction, and automatically configures a symmetrical mapping (with the
input_codepoint
By default, all the tables are initialized such that DSCPs are not altered by the mapping
operations. For example, an input DSCP value of n is always mapped to an output
DSCP value of n.
Asynchronous Transfer Mode (ATM) Module Installation and User Guide
diffserv examination
Specifies one of the 64 possible DiffServ code point values as the
input code point.
Specifies one of the 64 possible DiffServ code point values as the
output code point.
Applies the DSCP mapping to the egress direction.
Applies the DSCP mapping to the egress mapping table for the
non-congested state.
Applies the DSCP mapping to the egress mapping table for the
congested state.
Applies the DSCP mapping to the ingress direction.
and
no-congestion congestion
and
egress ingress
and
output_codepoint
function is disabled on the
keywords, the command applies the
keywords, the command applies the mapping to
values reversed) in the ingress direction.
Configuring QoS Functions
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