Subject: Changing the meaning of sec from 12 bits to 16 bits?

From: Pekka Nikander <[email-masked]>
Date: Tue, 10 Jun 2003 12:47:25 +0300

Again, for making our implementation easier...

Based on some early performance results that we've heard from
Jon, it looks like finding a suitable modifier for sec=1 or sec=2
is currently easily computable, while generating an sec=3 address
takes hours or days.

Now, comparing a fractional byte number of bits for zero
takes somewhat more code than just comparing a whole byte
number.  Thus, we'd like to suggest that instead of each
sec step meaning 12 bits that would be 16.

This would have a dual benefit.  Firstly, it would allow to
make the CGA checking code slightly easier.  Secondly, that
would protect us better in the future, allowing considerably
longer bits hash2 value.

Opinions?

--Pekka & Gonzalo

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From: Jari Arkko <[email-masked]>
Date: Wed, 11 Jun 2003 22:21:19 +0300

Pekka Nikander wrote:

> Thus, we'd like to suggest that instead of each

Sounds good to me.

--Jari

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From: Julien Laganier <[email-masked]>
Date: Wed, 11 Jun 2003 21:43:39 +0200

> is currently easily computable, while generating an sec=3 address

This confirms some of my early experiments.

> would protect us better in the future, allowing considerably

Given that generating a CGA with 12 or 24 bits is quite 'easy', as opposed to 
a 36 bits generation, I fully agree with this proposal.

Thanks,

--julien