Multihoming

Multihoming is a technique to improve the reliability of Internet connections of the IP network. To this end, the connection to the Internet via at least two ISP (Internet Service Provider, ISP). Turns out one of the internet provider, the router automatically switches off all routes that previously ran through this to get to the other provider.

A multihoming is realized mostly through a BGP router ( eg Cisco router or Linux server with quagga). Due to the different AS path lengths decides that which ISP connection is best suited for a particular connection. By using different tuning parameters (MED, Precedence ) certain ISPs can be individually preferred.

Multihoming requires usefully that the network with PI addresses ( Provider Independent) being worked on. Under these conditions, other traffic shaping mechanisms may be used to run any incoming data packets through an ISP, for example, and the outgoing of a second. Another (not really used ) is variant to divide the individual Internet services such as Web, FTP, database, etc. on the two internet lines.

• Internet