Issue203

Title Must define IPv4 well known multicast address
Priority bug Status chatting
Superseder Nosy List pcalhoun
Assigned To pcalhoun Topics

Created on 2008-09-25.01:00:36 by pcalhoun, last changed 2008-09-25.01:00:36 by pcalhoun.

Messages
msg592 (view) Author: pcalhoun Date: 2008-09-25.01:00:36
> Discuss:
> Section 3.3., paragraph 3:
> >   The WTP MUST send the Discovery Request
> >    message to either the limited broadcast IP address
(255.255.255.255),
> >    a well known multicast address or to the unicast IP address of
the
> >    AC.
> 
>   DISCUSS: http://www.iana.org/assignments/multicast-addresses does
not
>   list a well-known IPv4 multicast address reserved for CAPWAP, and
>   Section 15.1 only requests allocation of a new IPv6 multicast
address.
>   Which well-known multicast address should be used for CAPWAP with
>   IPv4?

Yes, since we state that multicast can be used for IPv4, we need to allocate a 
well known address. I have made a change to section 3.3, and a new IANA 
Considerations section.

<updated text>
3.3.  AC Discovery
[...]
   When the WTP attempts to establish communication with an AC, it sends
   the Discovery Request message and receives the Discovery Response
   message from the AC(s).  The WTP MUST send the Discovery Request
   message to either the limited broadcast IP address (255.255.255.255),
   the well known CAPWAP multicast address (xx.xx.xx.xx) or to the
   unicast IP address of the AC.  For IPv6 networks, since broadcast
   does not exist, the use of "All ACs multicast address" is used
   instead.  

15.1.  IPv4 Multicast Address

   This document requires a new IPv4 multicast address called
   "capwap-ac" from the Local Network Control Block IPv4 multicast
   address registry [to be removed upon publication
   http://www.iana.org/assignments/multicast-addresses].  The new
   multicast address is to replace the text xx.xx.xx.xx in Section 3.3.
</updated text>
History
Date User Action Args
2008-09-25 01:00:36pcalhouncreate