[Lsr] Flexible Algorithm - TE or not TE

Robert Raszuk <robert@raszuk.net> Fri, 04 December 2020 07:36 UTC

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From: Robert Raszuk <robert@raszuk.net>
Date: Fri, 4 Dec 2020 08:36:38 +0100
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To: lsr <lsr@ietf.org>, Tony Li <tony1athome@gmail.com>
Cc: Jeff Tantsura <jefftant.ietf@gmail.com>, "Acee Lindem (acee)" <acee=40cisco.com@dmarc.ietf.org>, Aijun Wang <wangaijun@tsinghua.org.cn>, Gyan Mishra <hayabusagsm@gmail.com>
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Subject: [Lsr] Flexible Algorithm - TE or not TE
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Hi,

Adjusting subject to reflect topic.

Wow .. I did not think this will start such a debate :)

To me this is actually very simple. Flex Algo is still IMO an SPF with
additional two new factors:

* You have ability to exclude links or nodes from your computation
* You run traditional SPF based on any metric (static or dynamic) you can
imagine

Did I miss something?

Yes the above will allow you to steer traffic other then based on the IGP
metric, but as you all recall when we started to deploy MPLS-TE Cariden was
claiming that they can accomplish TE without MPLS too by properly adjusting
IGP metrics while observing traffic demands.

Cheers,
Robert