The MPLS WG Archive

[Ajay Simha <asimha@cisco.com>]

On Wed, 3 Oct 2001, krishnakanth.rao wrote:

k>1. How are label switch paths created

They are created using control protocols like LDP/RSVP.

k>2. Are they created before traffic starts flowing in an MPLS network or
k>can they be created once packets starts flowing.

They are typically created when LSRs' routing protocols converge.  But they
could be created after packtes are being forwarded using hop-by-hop forwarding
(IP).

k>3. How do individual routers (LSR) know which label to distribute to its
k>peer for different LSP's since the label value has a ditect bearing to the

They are generated randomly by each LSR on a per-fec basis and the LSR then
tracks which labels are assigned to which FEC.  It could also keep track of
this on a per-interface/per-fec basis.

k>LSP's. 4. Are the LSP's created by the network administrators

Could be for TE....

You should read the RFCs/Drafts they explain most of this.

-ajay
k>
k>Krishnakanth
k>

-- 
Ajay Simha
MPLS Deployment Engineer
IOS Technology Division
(919) 392-3141

"Study as if you were to live forever
 Live as if you were to die tomorrow"

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