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"
wrote:
> -----Original Message----- > From: Owen DeLong [mailto:owen@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
> 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
> 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
10 these 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
<leigh.porter@ukbroadband.com> than the
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
CDNs 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
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