IP Address Allocation
5-5
8000-A2-GB21-30
April 1998
In the previous illustration:
H Each of the four DSL ports is on a different subnetwork of size 16, and the
subnet mask for the four ports is 255.255.255.240.
H The LAN port (10BaseT port) IP address is 200.200.200.
n
(where
n
can be
any valid IP address, but cannot be an IP address within the other subnets),
and its subnet mask is 255.255.255.0.
The illustration on page 5-6 shows one NSP connected to one DSL card, while
the illustration on page 5-7 shows 16 NSPs connected to one DSL card. On
page 5-7, the NSP router is multihomed to support all 16 NSPs. Also, each RTU
has 32 end-user systems (ES).
In summary, if 32 end-user systems are connected to the DSL card’s port 1 (s1c)
and all are using host addressing, then 32 host routes must be configured on the
RTU. If they are using structured subnet addressing, then only one route is
configured on the 5446 RTU or the router attached to a 5546 RTU. Remember
that structured subnet addressing applies only to the 5446 and the 5546 RTUs.
