User's Manual

Connecting the Router to a Blacker Front End

308625-14.00 Rev 00

4-3

BFE Addressing

You can enable BFE support on individual IP interfaces. Once enabled, the router

uses the BFE address-resolution algorithm to map IP addresses to corresponding

X.121 addresses.

BFE IP-to-X.121 address translation differs from standard DDN address

translation. Each physical router-to-BFE connection is identified by a BFE X.121

network address and a BFE IP address. The format of a BFE X.121 address is:

zzzzzpdddbbb

All BFE hosts are members of Class A IP networks. The format of a BFE IP

address is as follows:

nnnnnnnn.Zpppdddd.ddddddbb.bbbbbbbb

BFE supports only physical addressing. It does not support logical addresses or

subaddresses.

zzzzz

is 0

is the BCD encoding of the port ID

ddd

is the BCD encoding of the domain ID

bbb

is the BCD encoding of the BFE ID

nnnnnnnn

identifies the network ID in bits

is 0

ppp

is the port ID in bits

dddd.dddddd

is the domain ID in bits

bb.bbbbbbbb

is the BFE ID in bits