Re: [Lsr] Flexible Algorithm - TE or not TE

"Acee Lindem (acee)" <acee@cisco.com> Fri, 04 December 2020 12:23 UTC

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From: "Acee Lindem (acee)" <acee@cisco.com>
To: Robert Raszuk <robert@raszuk.net>, lsr <lsr@ietf.org>, Tony Li <tony1athome@gmail.com>
CC: Jeff Tantsura <jefftant.ietf@gmail.com>, Gyan Mishra <hayabusagsm@gmail.com>, Aijun Wang <wangaijun@tsinghua.org.cn>, "Acee Lindem (acee)" <acee=40cisco.com@dmarc.ietf.org>
Thread-Topic: [Lsr] Flexible Algorithm - TE or not TE
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Date: Fri, 4 Dec 2020 12:23:22 +0000
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Subject: Re: [Lsr] Flexible Algorithm - TE or not TE
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From: Lsr <lsr-bounces@ietf.org> on behalf of Robert Raszuk <robert@raszuk.net>
Date: Friday, December 4, 2020 at 2:37 AM
To: lsr <lsr@ietf.org>rg>, Tony Li <tony1athome@gmail.com>
Cc: Jeff Tantsura <jefftant.ietf@gmail.com>om>, Gyan Mishra <hayabusagsm@gmail.com>om>, Aijun Wang <wangaijun@tsinghua.org.cn>cn>, "Acee Lindem (acee)" <acee=40cisco.com@dmarc.ietf.org>
Subject: [Lsr] Flexible Algorithm - TE or not TE

Hi,

Adjusting subject to reflect topic.

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

To TE or not to TE – that is the question…

You guys obviously have more time on your hands than myself but feel free to continue 😉

Thanks,
Acee

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