Subject: Re: draft-housley-binarytime-00.txt

From: Peter Sylvester <[email-masked]>
Date: Wed, 1 Sep 2004 19:36:11 +0200 (MEST)

> >The document states the rationale.  No conversion to operating system
> >representation and it is smaller.  In what way do you find it limiting?
> 
> It doesn't go beyond 2038, whereas UTCTime at least goes to 2050.

Some thoughts: 

The value is an ASN.1 INTEGER, not a time_t or whatever. 

The format IS flexible because it allows any integre size. It may just
happen that implements will wake up 33 years and find out that their
asn1 decoding of this INTEGER cannot convert higher numbers.. 

There are machines where the internal format of time is not seconds
since 1.1.70, ...

Showing this time to a user always requires some conversion, while 
displaying a generaizedtime does not. 

The few octes advantadge over generalizedtime seems small compared to the 
size of a signature. And treatment of generalized time is necessary anyway
because of dates in certs. 

> 
> The proposal isn't so much limiting as... bizarre.  The ASN.1 time formats
> have been around forever. everything supports them, and this proposal is for a
> format that isn't even as "flexible" as the not-very-flexible UTCTime.  What
> real problem is this addressing?  Why a time_t?  Why not a 64-bit time to keep
> the Java guys happy?  Or the Windows nanoseconds-since-1600 time?  Or the
> Macintosh seconds-since 1904?  You could make it a choice, so no-one would
> feel left out, with at least one of the choices being an identified-by-OID
> value so everyone could add their own favourite oddball format...
> 
> Peter.
> 
>

---

From: Russ Housley <[email-masked]>
Date: Wed, 01 Sep 2004 14:04:41 -0400

>asn1 decoding of this INTEGER cannot convert higher numbers..

Yep.

>There are machines where the internal format of time is not seconds

I agree.  However, very simple math can be used to make the 
conversion.  However, conversion from UTCTime and GeneralizedTime is a bit 
more complicated.  I do admit that operating systems provide the necessary 
routines to handle this in a few lines of code.

>displaying a generaizedtime does not.

Display to a human is not the biggest concern.  Date comparison is a much 
bigger deal to me.  Integer comparison is easy, even when multi-precision 
integers are involved.

>because of dates in certs.

Yep.  I think that BinaryTime has other uses too.

Russ