Re: Fwd: Re: SE style in optical networks

[Suresh Katukam <skatukam@cisco.com>]

Zhi, Sudheer and others,

Looks like this was lost in all other mails.. So please take a look
at this..

At 03:03 PM 4/12/2002 -0700, Suresh Katukam wrote:


>>Tom and all,
>>
>>I think everyone seemed to pick on my terminology or misinterpreted
>>what I said.
>>
>>Here is an example:
>>
>>          1+1                        1+1
>>A ----------------B --------- C ------------D
>>                      \          /
>>                        \       /
>>                           E
>>
>>
>>A - B & C - D 1+1 line protected
>>B - C, C - E, B - E are all unprotected links.
>>
>>Say, one wants to create a protected LSP from A to D.
>>then, you would create one primary LSP from A to D via
>>A - B - C - D, and then you would create another LSP
>>from A to D using SE style ( to indicate that this is an
>>alternate path for same Tunnel ) via A - B - E - C - D.
>>This way B - C is protected by B - E - C.
>>
>>B - C - E is not configured as a UPSR. All unprotected links.
>>Virtual UPSR can be created such a way that B has a bridge
>>and C has a selector. Ofcourse, for bidirectional LSP, you need
>>the same thing in the opposite direction too.
>>
>>Now, what do you call this kind of protection? Protected LSP?
>>But not 1+1 path protected  - since it is not end-to-end path
>>protected.
>>
>>To clarify again, this is when you would use SE style.
>>
>>Thanks
>>Suresh
>>
>>
>>At 01:17 PM 4/12/2002 -0400, Thomas D. Nadeau wrote:
>>
>>
>>>>This can be used to set up Protected circuits which may contain
>>>>1+1 lines and 1+1 path protected segments. So on 1+1 line
>>>>protected segments, you Share the bandwidth among primary
>>>>and alternate paths.
>>>
>>>         You do not share the bandwidth across 1+1 circuits. You
>>>double-book the bandwidth because the same packets are
>>>sent twice: once over each LSP.  You only share bandwidth
>>>with 1:N.
>>>
>>>         --Tom
>>>
>>>
>>>>Setting up protected circuits is not considered
>>>>in detail so far. Hopefully, P&R design team will consider this..
>>>>
>>>>Thanks,
>>>>Suresh
>>>>
>>>>At 04:32 PM 4/12/2002 +0530, Khuzema Pithewan wrote:
>>>>>Hi,
>>>>>
>>>>>How does SE style of RSVP signalling fits in the optical nature of network
>>>>>i.e. in wavelength, TDM switching etc.
>>>>>
>>>>>  In other words, How two lsp can share resource in optical networks??
>>>>>
>>>>>Regards,
>>>>>Khuzema.
>>>
>>>
>>>
>>>------------------------------------------------------------------------
>>>Mathematics is the supreme nostalgia of our time.
>