Border Gateway Protocol - Avaya 8800 Planning And Engineering

For the direct connections, protocol-based VLANs (IP and PPPoE) are required to achieve
traffic separation. The disabling of routing on each port is not required because routed IP
VLANs are not configured on port 2 (they are for indirect connections).
Figure 48: Direct PPPoE and IP configuration

Border Gateway Protocol

Use Border Gateway Protocol (BGP) to ensure that the switch can communicate with other
BGP-speaking routers on the Internet backbone. BGP is an exterior gateway protocol designed
to exchange network reachability information with other BGP systems in the same or other
autonomous systems (AS). This network reachability information includes information about
the AS list that the reachability information traverses. By using this information, you can prune
routing loops and enforce policy decisions at the AS level.
BGP performs routing between two sets of routers operating in different autonomous systems
(AS). An AS can use two kinds of BGP: Interior BGP (IBGP), which refers to the protocol that
BGP routers use within an autonomous system, and Exterior BGP (EBGP), which refers to the
protocol that BGP routers use across two different autonomous systems. BGP information is
redistributed to Interior Gateway Protocols (IGP) running in the autonomous system.
BGPv4 supports classless inter-domain routing. BGPv4 advertises the IP prefix and eliminates
the concept of network class within BGP. BGP4 can aggregate routes and AS paths. BGP
aggregation does not occur when routes have different multiexit discs or next-hops.
Planning and Engineering — Network Design

Border Gateway Protocol

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