The MPLS WG Archive

Cell Relay Retreat>MPLS WG Archive>month:2001-Jul> msg00411



[Date Prev][Date Next][Thread Prev][Thread Next]  
  [Date Index][Thread Index][Author Index][Subject Index]

Transport address --- TCP SESSIONS

  • From: Abhijit Gadgil <gabhijit@ee.iitb.ac.in>
  • Date: Tue, 24 Jul 2001 10:30:41 +0530 (IST)
  • cc: LDP Hello <ldp_hello@yahoo.com>, <mpls@UU.NET>

cks>>
cks>> Hi ; My question is regarding the Transport address in the LDP hello
cks>> ...
cks>>
cks>> Is it reasonable for a router to add its ROUTER ID into the Transport
cks>> TLV of hello...
cks>> consider
cks>>                        b1 > a1, b2 > a2, b3 > a3
cks>>
cks>>       _______                       ________
cks>>      |LSR A  |a1 <---L1-------> b1 |LSR B   |
cks>>      |ID:a1  |a2 <---L2-------> b2 |  ID:b1 |
cks>>      |_______|a3 <---L3-------> b3 |________|
cks>>
cks>>
cks>> Say LSR A always send ITS routerID (a1)  as the transport TLV in Hello
cks>> instead of its Interface IP addresses... TCP session will be
cks>> established properly on LINK L1
cks>>
cks>> Now trasport Address in Hellos on L2 & L3 is a1 and LSR B will try to
cks>> establish TCP session with address a1 for interfaces b2 & b3 and that
cks>> will be through link L1 again ...   LINKS L2 & L3 will never be
cks>> utilized ...

Not necessarily they should go out of link L1. They may go out of link L2,
L3 (Perhaps what u r refering here is loopback router address - which
typically would be router id, but not necessarily.)  And it depends more
upon the implementation of the TCP/IP stack in Box A.

So the answer to the question below is Yes!

cks>> So my question is IS IT VALID/ACCEPTABLE to use ROUTER ID as the
cks>> TRANSPORT ADDRESS INSTEAD of INterface address ...???


-abhijit