Re: ISSUE: Checkgroups control messages

["Charles Lindsey" <chl@xxxxxxxxxxxxxxxx>]

In <EBCFDD6D-5066-45C4-A322-D10C78B07039@xxxxxxxxxxxxxx> Thorfinn <thorfinn@xxxxxxxxxxxxxx> writes:

>On 23 Sep 2008, at 11:49, Russ Allbery wrote:

>>
>> Thorfinn <thorfinn@xxxxxxxxxxxxxx> writes:
>>
>>> 640kb should be enough for anyone. Um. :-)
>>>
>>> That is, yes, 32 bit unsigned integer is better, not 15 bit.
>>
>> Just to clarify, the current draft has no limit at all.  I think  
>> it's safe
>> and reasonable to add a limit of 2^32 - 1, but I'm always nervous  
>> about
>> adding limits on values because you never know when you might want  
>> them to
>> be larger later.
>>
>> On the other hand, Julien has a good point that implementers aren't  
>> going
>> to add a bigint implementation just to check sequence numbers.


>*nod* 64 bit is becoming fairly prevalent, and that should certainly  
>be enough.

>That said - the DNS world is pretty used to using a 32 bit integer  
>circle for comparison.

>Looking at the current USEPRO text... *ponder* Serial number MUST  
>increase.  That is definitely a problem - you certainly can run out of  
>32 bit integer.  It's not all that likely, but it's certainly possible.

Well, it has taken 30 years for a few heavily populated groups to come
within sight of overflowing the 32-bit article numbers, and the number of
checkgroups messages sent is many orders of magnitude less than what such
groups have seen. So I think 32 bits is fine. People still regard 32 bits
as the 'normal' length of an integer, even though modern hardware is able
to cope with 64bit, especially for addresses.

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
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