Re: AToM (EoMPLS) label stack

Hi,

AToM generally uses 2 label stack.

Top label: Tunnel label (This label is same as the one in normal IGP setup.
Some times also called as IGP label) - This is used to carry packet to
remote PE. This label binding info you getit from 'show mpls ldp bindings'.

Bottom label: VC label/PW label - This is to identify Attachment Circuit.
This you get it from 'show mpls l2 vc binding'. You can also check label
stack with 'show mpls l2 vc detail'.

Thanks,
Srinivas

On Tue, Feb 22, 2011 at 2:52 PM, GAURAV MADAN <gauravmadan1177_at_gmail.com>wrote:

> Hi All
>
> Sorry for asking this question .. don't have a setup to try .. If
> someone could please clarify ..
>
> I am referring the AToM chapter in "MPLS config on Cisco IOS " book .
> I am referring to Ethernet as my L2 circuit (between PE and CE) .
>
> The confusion is :
>
> 1) "sh mpls forwarding-table" as well as data plane diagram for EoMPLS
> shows 2 labels . Outer will be MPLS label (used in MPLS core) and
> inner will be L2 circuit Label .
>
> 2) But when the book talks of "how AToM works" ; it talks of something
> like Tunnel Label and VC Label imposed by PE .
>
> Tunnel label : To propagate from PE-ingress to PE-egress
> VC Label : Used by PE-Egress to get where to send frame (out which
> interface) ::::: Just like your MPLS VPN label in L3....
>
> Now my query is regarding the label stack .. Can someone please tell
> me if its a 2 label stack or a 3 label stack .
> Can someone please tell me exact inner / outer labels .
>
> I will simulate this as soon as i have access to devices ,.... But if
> someone can answer ; it will be great .
>
> Thanks
> Gaurav Madan
>
>
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Received on Tue Feb 22 2011 - 16:01:15 ART