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Re: ISP customer assignments
From: Cord MacLeod <cordmacleod () gmail com>
Date: Tue, 13 Oct 2009 16:34:27 -0700
On Oct 13, 2009, at 4:26 PM, Chris Adams wrote:
Once upon a time, Michael Dillon <wavetossed () googlemail com> said:How many addresses do you like on point-to-point circuits?That will become one of those great interview questions, because anyone who sayssomething like "a /127" or "a /64" will be someone that you probably don't want to hire. The right answer is to explain that there are some issues surrounding the choice of addressing on point-to-point circuits and there has even been an RFC published discussing these issues, RFC 3627 <http://www.ietf.org/rfc/rfc3627.txt>Still learning here, so please go easy... I read the above, and I see section 4 item 3 says:The author feels that if /64 cannot be used, /112, reserving the last16 bits for node identifiers, has probably the least amount of drawbacks (also see section 3). I guess I'm missing something; what in section 3 is this referring to? I can understand /64 or /126 (or maybe /124 if you were going todelegate reverse DNS?), but why /112 and "16 bits for node identifiers"on a point-to-point link?
I'm actually completely unclear why people would use anything but a / 126 in 90% or more of cases. For all intensive purposes a /126 translates to a /30 in IPv4. Do people assign /24's to their point to point links today with IPv4? What's the point of a /64 on a point to point link? I'm not clear why people would intentionally be so frivolous with their IP space simply for the sake of "because I can."
Current thread:
- Re: ISP customer assignments, (continued)
- Re: ISP customer assignments Owen DeLong (Oct 16)
- Re: ISP customer assignments - and CIDR James R. Cutler (Oct 16)
- Re: ISP customer assignments Valdis . Kletnieks (Oct 13)
- Re: ISP customer assignments Mark Smith (Oct 13)
- Re: ISP customer assignments Matthew Petach (Oct 13)
- Re: ISP customer assignments Joe Abley (Oct 13)
- Re: ISP customer assignments Marco Hogewoning (Oct 13)
- Re: ISP customer assignments Scott Morris (Oct 13)
- Re: ISP customer assignments Michael Dillon (Oct 13)
- Re: ISP customer assignments Chris Adams (Oct 13)
- Re: ISP customer assignments Cord MacLeod (Oct 13)
- Re: ISP customer assignments James Hess (Oct 13)
- Re: ISP customer assignments Kevin Loch (Oct 13)
- Re: ISP customer assignments Leo Bicknell (Oct 13)
- Re: ISP customer assignments Chris Adams (Oct 13)
- Re: ISP customer assignments Leo Bicknell (Oct 13)
- RE: ISP customer assignments TJ (Oct 13)
- Re: ISP customer assignments Nathan Ward (Oct 13)
- Re: ISP customer assignments Chris Adams (Oct 13)
- Re: ISP customer assignments Nathan Ward (Oct 13)
- Re: ISP customer assignments Michael Dillon (Oct 15)