From: ccie2be (ccie2be@nyc.rr.com)
Date: Wed Apr 27 2005 - 19:32:15 GMT-3
Hi guys,
Now that I understand how 6to4 tunnels work thanks to Simon Hart, I'm going
to try to understand how ISATAP works as well.
I know how to configure it - that's clear enough from the Doc-CD but I'd
like to understand how the destination ipv4 is derived for the encap ipv6
packet.
Consider this example:
|----------- ipv6 --------- | ---- ipv4 --- | -- ipv6 --- |
host A ------ rtr-A ------- rtr-B ------ rtr-C --- host C
Assume that host A knows host C's ipv6 address and wants to send traffic to
host C. Also, assume the following:
rtr-A is the default gateway for host A.
rtr-B and rtr-C are configured for isatap.
rtr-A and rtr-B are running an ipv6 IGP, so rtr-A knows how to reach rtr-B.
How does rtr-A know to send packets to rtr-B for delivery to rtr-C?
How does rtr-B know what ipv4 destination address to use to get packets to
rtr-C?
In this example, there are only 2 "border" routers, rtr-B and rtr-C
surrounding a "core" ipv4 network, but I imagine there could be any number
of border routers. Is that true?
TIA, Tim
This archive was generated by hypermail 2.1.4 : Tue May 03 2005 - 07:55:09 GMT-3