What is dynamic BGP?

BGP dynamic routing enables advertisement of self-service (private) network prefixes to physical network devices that support BGP such as routers, thus removing the conventional dependency on static routes. The feature relies on address scopes and requires knowledge of their operation for proper deployment.

What is BGP unnumbered?

Using the IPv6 link-local address as a next hop instead of an IPv4 unicast address, BGP unnumbered saves you from having to configure IPv4 addresses on each interface. When you use BGP unnumbered, BGP learns the prefixes, calculates the routes and installs them in IPv4 AFI to IPv6 AFI format.

What is keepalive BGP?

Keepalive timer BGP systems exchange keepalive messages to determine whether a link or host has failed or is no longer available. In conjunction with the hold timer, the keepalive timer indicates whether a router is reachable to its BGP peer.

Does BGP authenticate path information?

All BGP protocol exchanges can be authenticated to guarantee that only trusted routing devices participate in autonomous system (AS) routing updates. By default, authentication is disabled.

What is peer group in BGP?

A peer-group is a set of BGP neighbors that shares the same outbound policy, where the inbound policies might be different. In general iBGP peers receive the same updates all the time, making them ideal for arrangement for a peer group.

What are the four types of BGP messages?

BGP runs by sending five types of messages: Open, Update, Notification, Keepalive, and Route-refresh. These messages use the same header format.

What is route refresh in BGP?

The BGP Enhanced Route Refresh feature provides a way for Border Gateway Protocol (BGP) to find route inconsistencies, and in that unlikely event, to synchronize BGP peers without a hard reset. The feature is enabled by default; there are two optional timers.

How does BGP authentication work?

BGP authentication enables the routers to share information only if they can verify that they are talking to a trusted source, based on a password (key). TCP MD5 authentication between BGP peers verifies each transmitted message sent via the BGP session.

What is MD5 in BGP?

BGP peers can be configured with an MD5 algorithm (introduced in RFC 2385) which support routing authentication. When MD5 authentication is enabled, it computes an MD5 cryptographic hash over the TCP “pseudo header”, which includes the IP addresses used, the BGP packet carried in the TCP segment and a secret password.

What is remote as in BGP?

To identify a neighbor as internal to the local autonomous system, use the neighbor remote-as command to specify the same autonomous system number as specified by the router bgp command. Otherwise, the neighbor is external. Use the neighbor remote-as command to create a peer entry in the BGP neighbor table.