Refer to the exhibit. QPPB is being used by the service provider (AS30). The table-map and route-map called “important” are implemented on router POP A. The command bgp-policy destination ip-prec-map is applied to the interface between POP A in AS30 and NAP (AS40).
Which QoS action would have to be applied on POP B in AS30 to ensure that the traffic from the NAP (AS40) to the customer (AS20) will be marked with an IP precedence of flash?
A.
Traffic from AS20 must have the community attribute set to 10:50 in a route-map, and send-community must be specified.
B.
No actions are needed. Traffic must be marked in AS20 by the customer as 10:50 before it arrives at the service provider.
C.
Traffic from AS20 must have the extended community attribute set to 10:50 in a route-map, and send-community extended (or send-community both) must be specified.
D.
Traffic from AS20 must be automatically marked via an inbound QoS map on POP B, resulting in the community attribute set to 10:50.
Explanation:
BGP is an inter-domain routing protocol that exchanges reachability information with other BGP systems. The QoS policy propagation via the BGP feature allows classifying packets based on access lists, BGP community lists, and BGP AS paths.
QPPB uses BGP attributes to advertise CoS to other Routers BGP communities are usually used Domain.com
to propagate CoS information bound to IP networks Packet classification policy can be propagated via BGP without having to use complex access lists at each of a large number of border routers A route map is used to translate BGP information into IP precendence or QoS roup QPPB can only classify and mark inbound packets Propagate the CoS by encoding it into BGP attributes BGP Communities AS Paths IP prefixes Any other BGP attribute Translate the selected BGP attribute into either: IP Precedence QoS group Enable CEF and packet marking on interfaces