That makes very little sense to me since the smaller providers can get a /22 directly from ARIN. I, personaly, would never purchase service from a provider that insisted on sticking me behind NAT. SPRINT PCS does not NAT my cellphone. I receive a dynamic address at connection time, but, it is a real address. What they do that annoys me is they block UDP Port 53 to non-sprint nameservers, and, the phone browser is hard-coded to a particular sprint HTTP Proxy server. If the practice is becoming more common, that is very unfortunate. Owen --On Tuesday, April 19, 2005 9:09 AM -0400 Philip Matthews <matthews@nimcatnetworks.com> wrote:
Thanks to everyone who replied to my question about NAT usage in service providers (see original posting below). I got a lot of private replies, as well as those who posted to the list.
To summarize: It seems that there are quite a few providers who do this. I was told of at least 24 providers in the U.S., as well as providers in Canada, in Central America, in Europe, and in Africa which which do this.
It was suggested by a number of people that this was quite common on WiFi access and for data services on cell phones. I also heard about a number of cable access providers that do this, and its use on DSL access was mentioned a couple of times. (Many people didn't say what access types were affected, so I don't feel I can derive any meaningful statistics).
A number of smaller providers told me that they do it because they simply cannot get enough routable IP addresses from their upstream providers.
If I was to speculate, I would guess that the practice might be more common amongst newer providers, and with newer access methods on more established providers.
- Philip
Philip Matthews wrote:
A number of IETF documents(*) state that there are some service providers that place a NAT box in front of their entire network, so all their customers get private addresses rather than public address. It is often stated that these are primarily cable-based providers.
I am trying to get a handle on how common this practice is. No one that I have asked seems to know any provider that does this, and a search of a few FAQs plus about an hour of Googling hasn't turned up anything definite (but maybe I am using the wrong keywords ...).
Can anyone give me some names of providers that do this?
Can anyone point me at any documents that indicate how common this practice is?
- Philip
(*) Some IETF documents that mention this practice: - RFC 3489 - draft-ietf-sipping-nat-scenarios-00.txt (now expired, but available at
http://www.ietf.org/proceedings/02jul/I-D/draft-ietf-sipping-nat-scenari os-00.txt
-- If it wasn't crypto-signed, it probably didn't come from me.