L2VPN and MTU issue

Hi all

I know the break up of the MTU when doing a L2VPN setup. This was my break
up

Here is my breakdown of the MPLS MTU:

Ethernet Payload - 1500

802.1q header - 18

AToM Header - 4 (Required for ATM and FR only )

AToM Label - 4

LDP Label - 4

TE Label - 4

MPLS Fast Reroute - 4

Total = 1538

So If i have a MTU of 1500 on the core, whether the L2VPN packet will be
fragmented r else it will be dropped , I mean the L2VPN data as well as the
control pLane traffic.

WHen targeted LDP exchange control plane messages to bring up the T-LDP
session, they negotiate the Attachment circuit MTUs and not the Core side
MTUs .

But when the MTU is lesser on the core side, what problems will happen.
Will it fragment the packet or else it will attach any Header to find the
correct sequence of packets

Or else Control Word is used when fragmentation happens on the core.

Anyone came across this issue ?

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Received on Mon Oct 22 2012 - 19:33:38 ART