The MPLS WG Archive

["Qureshi, Muhammad A (Akber)" <mqureshi@lucent.com>]

Hi Defeng,

See my comments inline:

Regards,
Akber.

-----Original Message-----
From: lidefeng [mailto:lidefeng@huawei.com]
Sent: Tuesday, August 26, 2003 3:48 AM
To: mqureshi@lucent.com
Cc: mpls@UU.NET
Subject: Re: About "extra traffic" and "seperate LSP" in Y.1720


What traffic belongs to "extra traffic"?
[Akber] Extra traffic can be any traffic with the understanding
that it is using the capacity reserved for protection and in case 
of protection switching will be preempted.


----- Original Message -----
From: "lidefeng" <lidefeng@huawei.com>
To: <mqureshi@lucent.com>
Cc: <mpls@UU.NET>
Sent: Tuesday, August 26, 2003 3:44 PM
Subject: About "extra traffic" and "seperate LSP" in Y.1720


> I have some confusion about Y.1720,
>
> 1. What's the relation between "working traffic" and "extra traffic"?
[Akber] In context of 1:1 protection, extra traffic is utilizing the
capacity reserved for protection of the working traffic and in case 
of a failure along the working path will be preempted.
>
> 2. There is a concept "seperate LSP" in Y.1720,is it another LSP different
> from "working LSP" and "protection LSP",as shown in Figure5 and Figure6,if
> that is true,why the extra traffic need to be disconnected to make way for
> the protected traffic from the failed working connection when the working
> traffic is switched over to the protection LSP, as it is stated in section
> 7.1.1.2("Extra traffic" part)?
[Akber] Extra traffic is being carried on a separate LSP as you stated and
is using the reserved protection capacity. After the failure, working traffic
gets switched onto the protection LSP. If extra traffic is not disconnected
then the switched traffic on the protection LSP and the extra traffic on the
separate LSP will compete for the same resources. Therefore, it is recommended 
to disconnect the extra traffic.
>
> Could you please clarify it for me?
>
> Thanks
>
> Defeng Li
> Huawei Technologies
>