DSL

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Acceptable Use of DSL

Members of the ISP-DSL list discuss industry practice on Acceptable Use Policies (AUPs) for DSL services. A well-written AUP is a tool to prevent the abuse of broadband services.

[December 4, 2000]

On the ISP-DSL list in November, DI asked,

"My ISP prohibits two simultaneous users on the same DSL line. Is this a common prohibition? Can the ISP really tell if two users are on at the same time?"

GE pointed out that the problem may well be solvable with semantics:

"It might be worth checking to see if they state a distinction between two users and two computers in their Acceptable Use Policy."

SM suggested that there are a number of ways around this issue:

"The ISP will give you one IP address. Thus you cannot split the line and put in two DSL modems, as you will lose connection on both. You have to use a router and map internal IP addresses. Technically, you can map over 250 users on one DSL circuit; I do know of many firms that are running 50-75 computers on one simple DSL circuit with charming results.

Bottom line: if you want to do this, you need a router or proxy server. But be warned: proxy servers require that one computer be on and up all the time, and many are a pain to maintain even if they don't have conflicts and constant system crashes."

A number of respondents backed up SM's advice with specific examples:

[CC recounted] "I have DSL at home going into my Cisco 675 router, which uses Port Address Translation (PAT). There is absolutely no way for my ISP to have any idea how many computers I have behind my router, since I only use one public IP address for them all."

[SW added] "I use a Linksys BEFSR11 Ethernet router. Works fine, lasts a long time. Use DHCP [definition] and NAT [definition] for as many IP addresses as you will ever need to use on a DSL line. It's not rocket science."

—End

 

Related articles:
	[Oct. 25, 1999]	Protect Your ISP With A Strong AUP
	[May 26, 1999]	5 Stupid Things ISPs Do to Their AUPs