Hi Scott,
I was trying to reduce permutations, but maybe it makes sense to have
the following breakdown of independent decisions tomorrow:
- Shall the Tag/Type/Length fields occupy 8 bytes (as described in
the 64-bit proposal) or 12 bytes (as described in the 32-bit proposal)?
- Shall the Value field be aligned to 4 byte or 8 byte boundaries?
I suspect the preference may be to use 8 bytes for the Tag/Type/Length
fields, and align the Value field to 4 byte boundaries -- essentially a
hybrid of the 32-bit and 64-bit proposals. Do folks agree?
Thanks!
-Matt
Scott Kipp wrote:
1713B295CDD20E4DBB5E439C3BE15AA6CF9DC3@BRM-EXCH-2.corp.brocade.com"
type="cite">
Matt,
Thanks for putting this
together. It is clearer when you have diagrams like this. It seems
like we ought to reserve bits/octets if we aren't going to use them in
a field. It's kind of odd that the 32-bit proposal header takes up 3
words and the 64 bit proposal header takes up 2 words. The TTLV format
should be a different discussion than the bit alignment. I prefer the
TTLV format of the 64 bit alignment proposal, but either will do.
One thing your diagram doesn't
show is that padding in the 32-bit proposal is either 1 to 3 bytes
while the padding in the 64 bit proposal is 1 to 7 bytes to get the
alignment. Your examples in the other proposals clearly show this.
Thanks for clearing this up,
Scott
Hi Folks,
I've put together a diagram that shows the difference between the
32-bit and 64-bit proposals in graphic detail. For these types of
comparisons, words don't quite express the idea as well as pictures do.
As the poll showed, the group is about halfway split between 32-bit and
64-bit, and I'm hoping that this diagram will show that the 64-bit
proposal works just as well for 32-bit applications. :)
With any luck we'll reach a conclusion via e-mail and will be able to
have a quick vote in tomorrow's meeting to pick one of these
proposals. I do prefer the 64-bit option as more useful, but would be
happy to approve the 32-bit version if that's the group's favorite.
Let me know if you have any comments or questions!
Cheers,
-Matt
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