In: Computer Science
What is BGP? Explain how a network administrator of an upper-tier ISP can implement policy when configuring BGP.
First Question:
BGP stands for Border Gateway Protocol. It can be defined as a standardized exterior gateway protocol which is developed to interchange routing information and reachability information between various autonomous systems (AS) on the Internet. It is classified as a path vector protocol as well as a distance-vector routing protocol.
Second Question:
A tier-1 ISP B may not to carry transport traffic in the middle
of two other tier-1 ISPs (for example, A and C), with which B has
peering agreements. To develop this policy, ISP B would not display
to A paths those pass-through C, and would not show to C routes
those pass-through A.
Policy Based Routing can be composed by an administrator through
route maps on routers for:
(i) Modifying the following hop address.
(ii) Delivering traffic to a nearby router to revolution of the way.
(iii) By source or destination address, the directional flow of the traffic can be managed.
(iv) To modify the way traffic is delivered to a nearby router.
Please comment in case of any doubt.
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