<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> <HTML> <HEAD> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=utf-8"> <META NAME="Generator" CONTENT="MS Exchange Server version 6.5.7638.1"> <TITLE>Re: Ha: [address-policy-wg] RE: an arithmetic lesson</TITLE> </HEAD> <BODY>  To upset some more sentiments; compare v4 /24s with the available v4 unicast; do the same with v6 /24s and current v6 unicast space. Rough arithmetic shows then that in that line of reasoning, a v6 /24 is more comparable to a v4 /20. Remco ----- Original Message ----- From: address-policy-wg-admin@ripe.net <address-policy-wg-admin@ripe.net> To: Dmitriy V Menzulskiy <DMenzulskiy@beeline.ru> Cc: michael.dillon@bt.com <michael.dillon@bt.com>; address-policy-wg@ripe.net <address-policy-wg@ripe.net> Sent: Thu Dec 03 14:20:22 2009 Subject: Re: Ha: [address-policy-wg] RE: an arithmetic lesson On Dec 3, 2009, at 7:55 AM, Dmitriy V Menzulskiy wrote: > > > > > > On 3 Dec 2009, at 10:00, <michael.dillon@bt.com> wrote: > > > > > > > an IPv6 /24 and an IPv4 /24 use up the same percentage of the > total > > > > address space. > > > > > > How do you work that out? Please enlighten me. 2^24/2^128 x > > > 100 is many orders of magnitude smaller than 2^24/2^32 x 100: > > > gromit% bc > > > scale=50 > > > 2^24/2^128*100 > > > .00000000000000000000000000000493038065763132378300 > > > 2^24/2^32*100 > > > .39062500000000000000000000000000000000000000000000 > > > > > > There are of course the same number of IPv4 and IPv6 /24s. > > > > Percentage is calculated by dividing the number of things > > under consideration by the total number of things. When > > I used the word "an", I meant one thing. > > > > Assuming that the number of IPv4 and IPv6 /24s is 10 > > > > 1/10 = 1/10 > > > > Assuming that the number of IPv4 and IPv6 /24s is 8192 > > > > 1/8192 = 1/8192 > > > > Assuming that the number of IPv4 and IPv6 /24s is 2882873787 > > > > 1/2882873787 = 1/2882873787 > > > > Do you see a pattern forming? > > > > --Michael Dillon > > > > As I understand: > > IPv4 /24 is (Total IPv4)/(2^24) > IPv6 /24 is (Total IPv6)/(2^24) > > Or not ? > Not. The ratio you want, using your formalism, is (2^(size of address space - 24)) / (Total IPvX) which is 2^(N - 24) / 2^N = 1 / 2^24 (where N is the number of bits in the address space). Regards Marshall > > WBR, > > Dmitry Menzulskiy, DM3740-RIPE > This email is from Equinix Europe Limited or one of its associated/subsidiary companies. This email, and any files transmitted with it, contains information which is confidential, may be legally privileged and is solely for the use of the intended recipient. If you have received this email in error, please notify the sender and delete this email immediately. Equinix Europe Limited. Registered Office: Quadrant House, Floor 6, <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" /><st1:Street w:st="on"><st1:address w:st="on">17 Thomas More Street</st1:address></st1:Street>, <st1:address w:st="on"><st1:Street w:st="on">Thomas More Square</st1:Street>, <st1:City w:st="on">London</st1:City> <st1:PostalCode w:st="on">E1W 1YW</st1:PostalCode></st1:address>. Registered in <st1:country-region w:st="on">England</st1:country-region> and <st1:country-region w:st="on"><st1:place w:st="on">Wales</st1:place></st1:country-region> No. 6293383.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p> </body> </HTML>