On Sep 13, 2011, at 10:18 PM, Dan Wing wrote: >> One can do that with or without NAT. This claim that one cannot >> keep a network running without a service provider connected if you >> don't run NAT is a myth of dubious origin. > > If the hosts are running DHCP, and the ISP is running the DHCP > server? I guess they will fall back (after a while) to link-local > and continue on their merry way. >
That's some pretty big IFs. Even if I were using DHCP to get the prefix from my service provider via DHCP-PD, I'd back-stop that with some form of local DHCP server and deal with the need for manual intervention when the provider renumbered me. In my experience, getting renumbered is a rare enough experience that I don't pay Comcast $60/year for a static address. Owen >>> can accomplish this pretty easily, because the IPv4 addresses in >>> the home can be any IPv4 address whatsoever -- which allows the >>> in-home CPE ("B4", in Dual Stack-Lite parlance) to assign any address >>> it wants with its built-in DHCP server.) >>> >> >> There are other ways to accomplish this as well. > > -d > >>> -d >>> >>>> and less technically but relevant I think is to ask about cost? who >>>> pays? >> >> In some cases, ISPs will provide new CPE to their end users. In other >> cases, >> end-users will be expected to pay to upgrade their own. >> >> Owen >> >>>> >>>> >>>> Christian >>>> >>>> On 8 Sep 2011, at 15:02, Cameron Byrne wrote: >>>> >>>>> On Sep 8, 2011 1:47 AM, "Leigh Porter" >> <leigh.por...@ukbroadband.com> >>>> wrote: >>>>>> >>>>>> >>>>>> >>>>>>> -----Original Message----- >>>>>>> From: Owen DeLong [mailto:o...@delong.com] >>>>>>> Sent: 08 September 2011 01:22 >>>>>>> To: Leigh Porter >>>>>>> Cc: Seth Mos; NANOG >>>>>>> Subject: Re: NAT444 or ? >>>>>>> >>>>>>>> Considering that offices, schools etc regularly have far more >> than >>>> 10 >>>>>>> users per IP, I think this limit is a little low. I've happily >> had >>>>>>> around 300 per public IP address on a large WiFi network, granted >>>> these >>>>>>> are all different kinds of users, it is just something that >>>> operational >>>>>>> experience will have to demonstrate. >>>>>>>> >>>>>>> Yes, but, you are counting individual users whereas at the NAT444 >>>>>>> level, what's really being counted is end-customer sites not >>>> individual >>>>>>> users, so the term >>>>>>> "users" is a bit misleading in the context. A given end-customer >>>> site >>>>>>> may be from 1 to 50 or more individual users. >>>>>> >>>>>> Indeed, my users are using LTE dongles mostly so I expect they >> will >>>> be >>>>> single users. At the moment on the WiMAX network I see around 35 >>>> sessions >>>>> from a WiMAX modem on average rising to about 50 at peak times. >> These >>>> are a >>>>> combination of individual users and "home modems". >>>>>> >>>>>> We had some older modems that had integrated NAT that was broken >> and >>>>> locked up the modem at 200 sessions. Then some old base station >>>> software >>>>> died at about 10K sessions. So we monitor these things now.. >>>>>> >>>>>> >>>>>>> >>>>>>>> I would love to avoid NAT444, I do not see a viable way around >> it >>>> at >>>>>>> the moment. Unless the Department of Work and Pensions release >>>> their /8 >>>>>>> that is ;-) >>>>>>>> >>>>>>> >>>>>>> The best mitigation really is to get IPv6 deployed as rapidly and >>>>>>> widely as possible. The more stuff can go native IPv6, the less >>>> depends >>>>>>> on fragile NAT444. >>>>>> >>>>>> Absolutely. Even things like google maps, if that can be dumped on >>>> v6, >>>>> it'll save a load of sessions from people. The sooner services such >>>> as >>>>> Microsoft Update turn on v6 the better as well. I would also like >> the >>>> CDNs >>>>> to be able to deliver content in v6 (even if the main page is v4) >>>> which >>>>> again will reduce the traffic that has to traverse any NAT. >>>>>> >>>>>> Soon, I think content providers (and providers of other services >> on >>>> the >>>>> 'net) will roll v6 because of the performance increase as v6 will >> not >>>> have >>>>> to traverse all this NAT and be subject to session limits, timeouts >>>> and >>>>> such. >>>>>> >>>>> >>>>> What do you mean by performance increase? If performance equals >>>> latency, v4 >>>>> will win for a long while still. Cgn does not add measurable >> latency. >>>>> >>>>> Cb >>>>>> -- >>>>>> Leigh >>>>>> >>>>>> >>>>>> >>>> >> ______________________________________________________________________ >>>>>> This email has been scanned by the MessageLabs Email Security >>>> System. >>>>>> For more information please visit http://www.messagelabs.com/email >>>>>> >>>> >> ______________________________________________________________________ >>>>>> >>> >>>