Tugger the SLUGger!SLUG Mailing List Archives

Re: [SLUG] ipv6


Anand Kumria wrote:
On Mon, Dec 19, 2005 at 10:30:43PM +1100, Visser, Martin wrote:

Anand Kumria wrote :-


The site-local prefix (fe80) has been deprecated (rfc3879), instead you

want IPv6 local addresses (rfc4193) which you

can self-generate with tools such as:


http://www.hznet.de/tools/generate-uniq-local-ipv6-unicast-addr.sh
Hmm, I dropped off the IETF announce lists a few years ago so I have
missed this fairly significant change. One thing I noticed though was
that this script doesn't comply with the mentioned RFC. I am guessing it
may have been written against an earlier draft (yep, the script says
Sept. 2004).


Hmm, I thought I had updated the URL before I sent out my email.

Anyway, http://www.hznet.de/tools/generate-rfc4193-addr.sh is one
which seems to comply with the RFC.  It might be worthwhile checking
this as throughly as you have the last one though.


While it creates a pseudo-random address, a few problems I see are that
it uses FD00::/8 as the prefix (instead of FC00::/7 which means it only
tries to use half of the available space) and MD5 instead of SHA1 as the
No! This is what RFC 4193 call a "locally" assigned uniq ipv6 unicast address. In one of the former drafts the addresses with an L bit set to 0 are called "globally" assigned local ipv6 unicast addresses.
Currently these are not defined (See Chapter 3.2).

digest/randomizer. I know I am pedantic but one of the assumptions in
this RFC (section 3.2.1) is that all generators of locally assigned
global IDs use the same algorithm.


Holger, it is probably worthwhile if you generate a 303 - See
other  response if someone tries to access the earlier shell script.
Yes, done and thank you for the hint.

Regards,
Anand

Greets
Holger