Hi,
The reason dhcpv6 uses a specific client port is that it is specificly defined in RFC3315 section 5.2. Same applies to DHCP (RFC 1531 section 4.1).
http://www.ietf.org/rfc/rfc3315.txt
http://tools.ietf.org/html/rfc1531
Hope this helps
Harold Ritter
Sr Technical Leader
CCIE 4168 (R&S, SP)
harold@cisco.com
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