Subject: Re: [babel] Rtgdir early review of draft-ietf-babel-source-specific-01

From: Juliusz Chroboczek <[email-masked]>
Date: Sat, 20 Jan 2018 21:38:33 +0100

> Reviewer: Joel Halpern
> Review result: Not Ready

Dear Joel,

I have just submitted -02.  We would be grateful for a new review.

Thanks,

-- Juliusz

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From: Joel Halpern Direct <[email-masked]>
Date: Sat, 20 Jan 2018 16:16:01 -0500

You have nicely addressed all of my concerns.  Thank you.
Joel

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From: Toke Høiland-Jørgensen <[email-masked]>
Date: Sun, 21 Jan 2018 00:10:56 +0100

> I have just submitted -02.  We would be grateful for a new review.

Browsed through -02 and came across this somewhat puzzling sentence (at
the beginning of the third paragraph in section 1):

> The main application of source-specific routing is multihoming with
> multiple addresses, a technique for multihoming which, unlike
> multihoming, does not require the use of provider-independent
> addresses and does not cause excessive growth of the global routing
> table.

-Toke

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From: Juliusz Chroboczek <[email-masked]>
Date: Sun, 21 Jan 2018 18:35:48 +0100

>> addresses and does not cause excessive growth of the global routing

Good catch.  That's supposed to say "unlike classical multihoming".

-- Juliusz

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From: Juliusz Chroboczek <[email-masked]>
Date: Fri, 26 Jan 2018 21:15:45 +0100

Re-added the list to the discussion, in case somebody has an opinion.

I've finally settled on this:

   The main application of source-specific routing is a form of
   multihoming known as multihoming with multiple addresses.  When using
   this technique in a network connected to multiple providers, every
   host is assigned multiple addresses, one per provider.  When a host
   sources a packet, it picks one of its addresses as the source
   address, and source-specific routing is used to route the packet to
   an edge router that is connected to the corresponding provider, which
   is compatible with [BCP84].  Unlike classical multihoming, this
   technique is applicable to small networks, as it does not require the
   use of provider-independent addresses, or cause excessive growth of
   the global routing table.  More details are given in [SS-ROUTING] and
   [DSR].

It's a little verbose, but it has the following desirable properties:

  - it uses the keyword "multihoming with multiple addresses" from the outset;
  - it avoids excessive repetition of multihoming (except in the first sentence);
  - it avoids bragging (it claims the technique is more suitable in small
    networks, not generally better).

It's in git but not submitted yet, so I welcome further constructive
nit-picking.

-- Juliusz

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From: Toke Høiland-Jørgensen <[email-masked]>
Date: Sat, 27 Jan 2018 14:08:01 +0100

>    the global routing table.  More details are given in [SS-ROUTING] and

I like this version :)

-Toke

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From: Teco Boot <[email-masked]>
Date: Sat, 27 Jan 2018 16:51:50 +0100

I don't think "classical multihoming" is well defined. In some (...) 
small multihomed networks, NAT is used. Maybe add a few words that 
NAT isn't needed either?

Teco

> Op 26 jan. 2018, om 21:15 heeft Juliusz Chroboczek <[email-masked]> het volgende geschreven:
> 
> _______________________________________________
> babel mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/babel

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From: Gabriel Kerneis <[email-masked]>
Date: Sat, 27 Jan 2018 16:44:26 +0000

> small multihomed networks, NAT is used. Maybe add a few words that

I found it nice that it matches the terminology of the Wikipedia page on
multi homing, but I would understand some see this as a downside rather
than an upside ;-) I'm not sure it counts as a reliable data point for
well-definedness.

Gabriel

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From: Juliusz Chroboczek <[email-masked]>
Date: Sat, 27 Jan 2018 20:37:14 +0100

Hi Teco, it's been some time.

>     small multihomed networks, NAT is used. Maybe add a few words that

Dunno.  On the one hand you're probably right, on the other, the less said
about NAT the better.

> I found it nice that it matches the terminology of the Wikipedia page on multi
> homing,

I put it there ;-)