The MPLS WG Archive

[Snigdho Bardalai <sbardalai@yahoo.com>]

Hi,

Could you please help me understand how the NNHOP
Bypass tunnel works as described in Secion 6.5.

Consider the network below (from Section 1.2):

                [R8]
                    \
              [R1]---[R2]----[R3]----[R4]---[R5]
                         \\          //   \
                          [R6]===[R7]     [R9]

Say, labels available at R2 are L1 for the working
tunnel from R3 and L2 for the bypass tunnel from R6.

Again, labels available at R3 are L3 for the working
tunnel from R4.

Now when a packet is switched from the working tunnel
onto the bypass tunnel at R2 the label stack (as
described) will be L2->L1.

When the packet leaves R7 (the penultimate hop) the
label stack is L1.

At R4 it is expecting to L3, whereas it sees L1, won't
that be an error ?

Would appreciate a reply,
Thanks,
Snigdho

__________________________________________________
Do You Yahoo!?
Yahoo! Greetings - Send FREE e-cards for every occasion!
http://greetings.yahoo.com