Subject: Discussion: sharing options/extensions between DHCPv4 and DHCPv6

From: Ralph Droms <[email-masked]>
Date: Tue, 10 Oct 2000 12:03:44 -0400

Issue: Where appropriate, keep v4 and v6 options/extensions "the
same". Use the same option numbers. Use the same format (except for
16-bit type/length).

Summary: Bernie described certain DHCPv4 options as carrying
version-independent parameters such as domain names and URLs.  Any
option carrying an IP address would *not* fit into this category.
Such options would use the same option number and data format for both
DHCpv4 and DHCPv6 (although the option format would be different to
allow for 16-bit option codes and lengths in DHCPv6).

Current options that fall into this category would be described in a
single document (supplementary to and separate from the DHCCPv6
spec).  A new options that fits into this category would include a
statement that it is defined for both DHCPv4 and DHCPv6.  IANA would
be informed to assign option code numbers for these options in the
1-127 range for compatibility with DHCPv4.  DHCPv6 option codes in the
range 1-127 will be reserved for options defined for both protocols.

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From: Ted Lemon <[email-masked]>
Date: Tue, 10 Oct 2000 11:31:16 -0700

> allow for 16-bit option codes and lengths in DHCPv6).

I thought we were going to keep the options that have the same meaning
but whose contents are IPv6 addresses instead of IPv4 addresses the
same as well.   Is there any reason not to?

			       _MelloN_

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From: Ralph Droms <[email-masked]>
Date: Tue, 10 Oct 2000 14:48:27 -0400

>same as well.   Is there any reason not to?

I thought we had discussed that as well, but I couldn't find any reference 
to the idea in the archive - of course, I may have missed it.

In any event, retaining those options that carry IP addresses as sell makes 
sense to me.  I can imagine adding some text somewhere to the effect that 
the following options carry IPv4 addresses  whn carried in a DHCPv4 message 
and IPv6 addresses when carried in an IPv6 message (and be sure to fix the 
len field to be 4*n or 16*n)...

- Ralph