EW50 Industrial LTE Cellular Gateway
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BGP Scenario
Border Gateway Protocol (BGP) is a standard exterior
gateway protocol designed to exchange routing and
reachability information between autonomous systems
(AS) on the Internet. It usually makes routing decisions
based on paths, network policies, or rule-sets.
Most ISPs use BGP to establish routing between one
another (especially for multihomed networks). Very
large private IP networks also use BGP internally. The
major BGP gateway within one AS will link with other
border gateways for exchanging routing information. It
will distribute the collected data in AS to all routers in
other AS.
As shown in the diagram, BGP 0 is gateway to dominate
AS0 (self IP is 10.100.0.1 and self ID is 100). It links with other BGP gateways in the Internet. The
scenario is like a subnet in one ISP being linked with ones in other ISPs. By operating with BGP
protocol, BGP 0 can gather routing information from other BGP gateways in the Internet. It then
forwards the routing data to the routers in its dominated AS. Finally, the routers resided in AS 0
know how to route packets to other AS.