Re: [RPRWG] A question on IP over RPR
Precisely because RPR is a MAC-layer protocol that makes the
dual-ring(lets) appear as one LAN medium, default normal ARP should not
change, i.e. current IP-MAC binding would work just as it is. Normal
"ping" operations would (and should) work unchanged. The RPR MAC would
choose the proper ringlet to use based on its topology discovery and
ringlet determination. The operation is transparent to upper layer, just
like a MAC should do.
The RPR MAC _additionally_ provides a way for the client to specify
which ringlet (inner or outer) to use, so clients can override RPR
topology information. The client specifies it using the MAC data
services API, and it has nothing to do with an ARP operation per se.
For purposes of client choosing which ringlet to use - as Vinay
(Luminous) pointed out the client treats the ring as two ringlets and
decides which of the two is a better choice. Once it decides the ringlet
it uses RPR MAC services to select the ringlet.
Regards,
Pankaj
Jim Forster wrote:
Briefly, the L3 (IP) to L2 (RPR) binding is very similar to that on
Ethernet, with an extension. IP on Ethernet uses ARP to determine the
MAC address corresponding to
the next-hop IP address. On RPR we need this but we also need a
direction bit, or Ring ID -- which Ring, Inner or Outer to use. So ARP
proceeds pretty much like on
Ethernet to determine the next-hop MAC address. Then RPR topology
information is consulted to determine which ring to use, and the result
stored along with the
IP-MAC address binding information.
-- Jim
-----Original Message-----
From: owner-stds-802-17@xxxxxxxxxxxxxxxxxx
[mailto:owner-stds-802-17@xxxxxxxxxxxxxxxxxx]On Behalf Of lcwang@xxxxxxx
Sent: Thursday, January 31, 2002 1:12 AM
To: stds-802-17@xxxxxxxx
Subject: [RPRWG] A question on IP over RPR
Importance: High
A question of IP over RPR.
According to IP address, using routing protocol, a data
forwarding route can be selected. On the other hand, RPR may transfer
data through
its ring on both direction. How can consistency of L3 and L2 data
transfer be guaranteed?