Which two statements about the BGP community attribute are true? (Choose two.)
A.
Routers send the community attribute to all BGP neighbors automatically.
B.
A router can change a received community attribute before advertising it to peers.
C.
It is a well-known, discretionary BGP attribute.
D.
It is an optional transitive BGP attribute.
E.
A prefix can support only one community attribute.
A community is a group of prefixes that share some common property and can be configured with
the BGP community attribute. The BGP Community attribute is an optional transitive attribute of
variable length. The attribute consists of a set of four octet values that specify a community. The
community attribute values are encoded with an Autonomous System (AS) number in the first two
octets, with the remaining two octets defined by the AS. A prefix can have more than one
community attribute. A BGP speaker that sees multiple community attributes in a prefix can act
based on one, some or all the attributes. A router has the option to add or modify a community
attribute before the router passes the attribute on to other peers.
Reference:
http://www.cisco.com/