![]() ![]() However, things do get more complex in networks that span multiple locations and have routers that communicate with other networks over eBGP in more than one location. Adding a third and maybe even a fourth router in the same location doesn’t change that picture very much. ![]() This makes for a very simple BGP setup, where each router has the requisite filters to make sure only the network’s own IP address block(s) are advertised to the outside world over eBGP (external BGP), an all of one iBGP (internal BGP) session between the two BGP routers. The existing internal network is usually left running as before, typically using OSPF routing. Of course just one BGP router would also work, but the second one is required in case the first one fails. Usually, when an organization implements its first BGP configuration, they do this by putting two BGP routers at the edge of their network. And if an ISP doesn’t deliver the desired performance, connecting to another one is just a matter of getting the physical connection in place and a few lines in a router configuration-no renumbering of servers and other systems necessary. ![]() If, when using multiple ISPs, one ISP goes down, most of the time BGP automatically reroutes traffic over the other ISP(s). Implementing BGP has many benefits: it becomes possible to use multiple ISPs at the same time, augment transit service from an ISP with peering with other networks and isolation from problems in ISP networks. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |