The MPLS WG Archive

[Abhijit <gabhijit@ee.iitb.ernet.in>]

>-- Since you are assuming Ru is ReqWhenNeeded, does this mean that a MPLS
>scheme is possible with Ru being RequestWhenNeeded and Rd1 being
>PushUnconditional?? If yes this scheme is not mentioned in 5.2.1 Schemes for
>LSRs that Support Label Merging...
>If no it implies that Ru can be in RequestWhenNeeded only when Rd1 is
>PushConditional and inorder to determine if Rd1 is in PushConditonal its
>control mode is to be known by Ru.
>Hope I have made it clear.

Yes I certainly have missed this point. But i don't understand what
precludes Upstream LSR for requesting a Label from Downstream when
downstream is distributing it unslolcited with independent control. 


Consider e.g. 

Ru1
  \
    \
     Rd1 - - Rd2 - - Rd3 - - D
    /
  /
Ru2 

Let Rd1 be merge capable.. 

Why can Rd1 not send a request to Rd2 for some FEC F for packets destined
for D and coming from Both Ru1 and Ru2.. The fact that Rd2 distributes the
label bindings unsolicitedly won't require Rd1 to send the request. But in
any case it shouldn't prevent Rd1 from asking for it. How will it matter
if Rd2 distributes binding labels for FEC independent control or Ordered
control? So in any case Rd1 need not know Control mode of Rd2.. Is it
consisitent with architecture? 

And if Rd1 is also distributing bindings independently.. It will
distribute same binding to Ru1 and Ru2. Again why shd it stop Ru1 and Ru2
from requesting it anyways? Is this also consistent with architecture?
Again Ru1 and Ru2 need not know the control mode of Rd1 

am i missing something?

-abhijit