Best of the ISP-Lists

Static or Dynamic IP?

Members of the ISP-Wireless list discuss whether their customers prefer static or dynamic IPs. Businesses report that there are fans of both.

[January 27, 2001]

On the ISP-Wireless list in January, HV inquired,

"Seeing as there is a shortage of IPs, do you supply your customers with real public IPs or do you use NAT to connect them with the Internet?"

A number of respondents suggested it's best to stick with NAT:

[MKS offered] "I NAT everyone. If you want a public IP, it'll cost you extra."

[MO noted] "NAT has other benefits as well. It will stop your customers from running servers and such, and will give you more control over your network. We can always give a public IP to anyone who wants to pay for it."

[CR agreed] "If I were starting an ISP today, I'd sure go with private addressing and charge for routable addresses. You couldn't go wrong. You could even have several stages of addressing. First, dynamic, private address space. Second, static private address space with some port forwarding, priced per TCP port. Third, dynamic routable addresses. Fourth, static routable addresses. Fifth, static routable subnets. The difference is only a couple of dollars each way, but you could really have people think they're getting exactly the service they want—'safe' versus 'configurable.'"

Others contended that most users are more demanding than that:

[CFB observed] "People want IPs for external reachability. With current NAT technology, you're going to have a huge problem with things like NetMeeting, Internet appliances, and many other protocols that depend upon reachability from the outside. If there's one customer you want to retain, it's the technically inclined customer."

[KS agreed] "People want real IPs because of inherent problems with stand-alone applications resolving the IP address for identification purposes. Gamers, for instance, will not be happy with NAT, since most of the applications they use will suddenly stop working when they use NAT technology."

[FM warned] "NAT is an interesting—if often cumbersome—method of saving IP addresses. More often than not, the remedy is worse than the cure."

[BM explained] "We give all of our business customers one real IP for free. If they need more, they pay. Our home users get fake addresses and we NAT them here at the office, but believe it or not, most of our home users want real addresses and are willing to pay for them."

Still others, while divided on NAT in general, did note that it has advantages in terms of security:

[MC offered] "We provide NAT services for residential users as a quasi-firewall. They like being behind NAT."

[KS admitted] "NAT does give the most security in a new (or unskilled) user environment by effectively making all users invisible to the Internet. Security becomes a no-brainer."

[AM agreed] "Let me put it this way. My Mom and Dad, both 80 years old, have a 24/7 connection to the Internet. They know nothing about computers, and I don't see any reason to give them a public IP and set them up for anyone who might stumble across their IP. Many of our residential users are complete newbies and don't need their computer visible on the net 24/7. We haven't had a NATed user hacked yet…"

.

—End