[dhcwg] Assigning DHCPv6 option codes

Ralph Droms <rdroms@cisco.com> Wed, 23 January 2002 03:01 UTC

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Date: Tue, 22 Jan 2002 21:49:56 -0500
To: dhcwg@ietf.org
From: Ralph Droms <rdroms@cisco.com>
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Subject: [dhcwg] Assigning DHCPv6 option codes
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There is a potential collision problem between DHCPv4 and DHCPv6 option 
codes.  The DHCID RR uses the option code to identify the source of the 
information stored in the RR.  If DHCPv4 and DHCPv6 use overlapping option 
codes that identify different options, the source of the information in the 
RR will be ambiguous.  One proposed solution is to start numbering DHCPv6 
options at 256, to avoid collisions with DHCPv4 option codes.  Another 
solution is to assign new codes for the identification field in the DHCID 
RR, which then identify DHCPv4 or DHCPv6 options - or, perhaps other 
sources of information not encoded in a DHCP option.  For example, DHCID RR 
code 1 might identify the contents of the RR as a DHCPv4 client identifier, 
while DHCID RR code 2 might indicate a DHCPv6 DUID.  Comments on the two 

- Ralph

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