BGP is the basic protocol on the Internet, and due to it ISPs in the whole world are available. One day any serious ISP faces the protocol configuring. We hope that the material, given in this article, will become a good help for networking professionals on configuring dynamic routing via BGP.
In the article mechanisms of functioning of the dynamic routing protocol "BGP" are examined in details. Guides for configuring Cisco routers and Quagga package on basis of Gentoo Linux are given. A stand in which coherence between networks is realized due to routes promoted via BGP was assembled. On this stand a reconnection to a reserve channel on failure of the primary line has been tested.
Border Gateway Protocol (BGP, RFC-1265-1268,1467,1655,1771,1772) was developed by companies IBM and CISCO. A pair of BGP neighbors establishes a connection via TCP, port 179. Neighbors that belong to different autonomous systems should be available for each other directly; for neighbors from the same AS there is no such restriction because the internal routing protocol provides all necessary routes between nodes of the autonomous system. BGP routers exchange messages on changing routes. The maximal length of such a message is 4096 octets, the minimal is 19 octets. Each message has a header of a fixed size. The volume of an information field depends on the message type. Read more"