In message <4d4c8af8.1030...@brightok.net>, Jack Bates writes: > On 2/4/2011 5:11 PM, Mark Andrews wrote: > > No, a /48 is equivalent to a single IP. > > > > You loose a little bit with small ISPs as their minimum is a /32 > > and supports up to 64000 customers. The bigger ISPs don't get to > > waste addresses space. And if a small ISP is getting space from > > a big ISP it also needs to maintain good usage ratios. > > > > Read the rest of what I said again. In the layout I used, a /32 is a > /32. a /28 is a /28. Yet when you look at what is being assigned in IPv6 > and you look at what we assign in IPv4, it's pretty laughable. > > It took years for me to get to a /16 of IPv4; where a /16 of IPv4 is > small change for many large providers. In IPv6, a /16 is well out of my > league and much larger than many large providers will ever need.
A /16 of IPv4 is a /32 of IPv6 if you were only delivering 1 address per customer. If you were delivering /28's to customers that /16 is equivalent to a /36. /32 get assigned to ISPs. Those ISPs assign /48s downstream. The only place where that doesn't happen is ISP to ISP assignments (resellers). /48 get assigned to everybody else. The whole internet has shifted a minimum of 16 bits to the right. In many cases it will be 32 bits to the right. If ISP's only give out /56 then the shift is 24 bits. I used to work for CSIRO. Their /16's which were got back in the late 80's will now be /48's. Mark > >> A /28 (medium ISP) is equiv to an IPv4 /28. A /24 (high > >> medium, large ISP) is equiv to an IPv4 /24. A /16 (a huge ISP) is equiv > >> to an IPv4 /16. Get the picture? > >> > >> So, I currently route a /16 worth of deaggregated IPv4 address space > >> (sorry, allocation policy fault, not mine). There is NEVER a time that I > >> will be allocated an IPv6 /16 from ARIN. Heck, the most I'll ever hope > >> for is the current proposal's nibble boundary which might get me to a > >> /24. I'll never talk to ARIN again after that. > >> > >> > >> Jack > >> -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: ma...@isc.org