Avaya Configuring BFE Services Manual do Utilizador descarregar pdf (Página 22)

Configuring GRE, NAT, RIPSO, and BFE Services

1-2

305753-A Rev 00

A tunnel is a virtual point-to-point connection. It has as its end points the IP

addresses of two router IP interfaces, one serving as the source, the other serving

as the destination. When using GRE, remember that:

• This protocol is slower than native routing because packets require additional

processing.

• IP fragmentation of the packet can occur due to extra bytes introduced by

encapsulation.

• Troubleshooting the physical link when problems occur is difficult.

GRE tunnels support encapsulation of both the IP and IPX protocols.

For information about configuring and customizing GRE tunnels, see Chapter 2,

“Configuring GRE Tunnels.”

Network Address Translation (NAT)

Network Address Translation (NAT) allows private networks with unregistered

addresses to access the global Internet. As corporate networks grow, they often

use the Internet Protocol (IP) without acquiring registered network addresses. This

practice is acceptable as long as the network remains private. However, when

access to the global Internet is required, conflicts often arise between private local

addresses and global addresses registered to other users. Although it is possible to

restructure the local network, the task is difficult and costly, especially if there are

“well-known” servers with links or references to each other.

Using NAT, you can create a pool of registered IP network addresses. The router

remaps your unregistered current addresses to addresses allocated from this pool

when establishing a connection outside your company’s private or local network.

The connection appears to the host or server on the Internet as if it is from the

registered address space.

NAT routers can run in standalone or synchronized configurations.

Synchronization allows NAT routers to share address translation information. If a

NAT router fails, other NAT routers in a synchronized group can accommodate the

rerouted traffic.

For information about configuring and customizing NAT, see Chapter 3,

“Configuring Network Address Translation.”

1 2 ... 17 18 19 20 21 22 23 24 25 26 27 ... 179 180

Sem comentários

Avaya Configuring BFE Services Manual do Utilizador Página 22