their own independent connections to the global Internet. You could use internal BGP to move routing information between the individual networks that make up your enterprise network. An example of the group statement for such a configuration is group type igp peeras 64550 proto ospf This says that BGP will run as an internal gateway protocol, the ASN 64550 will be used within your enterprise network, and the routers you are exchanging updates with learn their routes through OSPF. The sample configuration concludes with two control statements: the export statements that define the routing policy. The first statement defines which internal routes are advertised to the external world. It tells gated to export to the autonomous system identified by ASN 164 all direct routes and all routes that the local router learns from OSPF. The final export statement defines the routes that gated accepts from the external world and advertises on the internal network. The first line of this statement is export proto ospfase type 2 This tells gated to advertise the routes via the OSPF protocol as autonomous system external (ASE) routes, which means the routes are clearly marked as routes learned from an external source. The type 2 parameter indicates that the routes come from a protocol that does not use a metric that is directly comparable to the OSPF metric. The alternative is type 1, which means that the metrics are directly comparable. However, BGP is a path-vector protocol, not a link-state protocol, and its metrics are not directly comparable to those used by OSPF. You know the routes were learned from BGP by looking at the rest of the export statement: proto bgp as 164 { all ; } This says that the routes being exported were received via BGP and that they come from the autonomous routing domain identified by ASN 164. Furthermore, the keyword all in this clause says that gated should accept all routes from that autonomous system. Instead of the keyword all, you can use specific addresses to accept only specific routes or the keyword restrict to block all routes. Note These discussions of OSPF and BGP show that routing can be a very complex topic. If you need to use a routing protocol that is more complicated than RIPv2, read more about it, and design your routing architecture before you try to configure a system. See Internet Routing Architectures by Bassam Halabi (Cisco, 1999) and IP Routing Fundamentals by Mark Sportack (Cisco, 1999) for additional information about routing protocols. Network Address Translation Network Address Translation (NAT) is an extension of routing that allows the router to modify the addresses in the packets it forwards. Traditional routers examine addresses, but they don’t change them. NAT boxes convert the IP addresses used on the local network to “official” IP addresses. This allows you to use a private network number and still have Internet access. The private network numbers defined in RFC 1918 are 225

Hint: If you are looking for very good and affordable webspace to host and run your tomcat hosting application check Virtualwebstudio tomcat web hosting provider