[j-nsp] MPLS transport / 1GE-LH

Cody Lerum clerum at transaria.com
Thu Oct 21 14:22:12 EDT 2004

This brings up an issue that I have been playing with. IF you are
running mpls lsps over an Ethernet network. What should the media MTU be
set to in order to make things as transparent as possible. The config
below has 1568, and I'm curious how you came to that number.

Ethernet	= 1514
MPLS Shim	= 4
VLAN-CCC	= 21	(Largest according to Juniper)
Total		= 1539


-----Original Message-----
From: juniper-nsp-bounces at puck.nether.net
[mailto:juniper-nsp-bounces at puck.nether.net] On Behalf Of
sthaug at nethelp.no
Sent: Thursday, October 21, 2004 2:58 AM
To: jf at probe-networks.de
Cc: juniper-nsp at puck.nether.net
Subject: Re: [j-nsp] MPLS transport / 1GE-LH

> i am working on setting up MPLS here and am wondering if someone has a

> small code sniplet/example of the following:
> FE port on M20 -> STM16 -> FE port on M20 I basically need to 
> transport FE over the existing link.

Basic port mode Martini tunnel, one end (we have several of these):

interfaces {
    fe-0/3/0 {
        mtu 1568;
        encapsulation ethernet-ccc;
        unit 0;

protocols {
    ldp {
        interface lo0.0;
    l2circuit {
        neighbor a.b.c.d {
            interface fe-0/3/0.0 {
                virtual-circuit-id 42;

Also, you need LSPs between the routers - these can be setup using
either LDP or TE/RSVP.

> Also i wonder if the Px-1GE-LH interfaces support CCC/MPLS vlans as 
> there is no -B version of these. Anyone knows?

Given that there is both PB-1GE-LH and PB-1GE-LX-B in the price list,
and the latter specifically mentions "supports CCC-for-VLANs" while the
former does not (and correspondingly for the PE- PICS), I would
definitely check with JTAC if you have the PB-1GE-LH or the PE-1GE-LH.

Steinar Haug, Nethelp consulting, sthaug at nethelp.no
juniper-nsp mailing list juniper-nsp at puck.nether.net

More information about the juniper-nsp mailing list