24 Dec
2000
24 Dec
'00
11:28 a.m.
At 09:01 AM 12/24/00 -0800, Bruce wrote:
Not to my mind. My router, having two Ethernet
ports, must have an IP
address for each of those ports. In order to be a part of the subnet on the
Cisco side, the port attached to it must have an IP address out of the
63.226 block I've been assigned. Ergo, that address is not available for a
machine.
But the router actually can use the *same* IP address on both sides. This
is running in what is known as 'unnumbered' mode. Since the diagram looks
like this:
+-------------+
| |
ISP +----------+ A Router B +-------> LAN
| |
+-------------+
Both interfaces A and B do not need unique IP addresses. They need only
one, since everything coming in port B that isn't for the local subnet goes
out port A and everything from the ISP is logically appearing at port B.
The the router to ISP path is a point-to-point link this works great.
--Chuck