Regardless of the media you decide upon, your ISP will be your true entrance point to the Internet. This may or may not be the same firm that provides the medium. When you send IP packets from your home network to the world, they aren’t really on the Internet until they get to your ISP, who then channels them onto the Internet through their gateways.

Your ISP does other necessary things, such as giving your home network an IP address, either static or temporary. It provides facilities to translate names to IP addresses, called domain name servers (DNSs), so you can ask for a web site by name and still reach it by its IP address.

They provide other services too, such as email and personal web pages. You may not need all the services they provide, even though they are bundled with the ones you do. Usually, the ISP is the agency you call first if you need your bill straightened out or some kind of technical help.

The phone companies that own the lines sell Internet access too, and they would dearly love for you to buy it from them. But no law says you have to. In fact, the Telecommunications Act of 1996 says that telephone companies have to provide for their own competition by allowing you to shop for the best ISP deal.

The dual-personality Telco/ISP arrangement can complicate troubleshooting a dead connection, because each half of the team can examine only part of the puzzle. This sometimes tempts them into jealous finger-pointing contests, with delays every time the problem is handed off between the Telco and the ISP.

Both want a happy customer, but neither is motivated to make their competitor look good. A handoff lag can also be a problem between departments within either agency. However you connect to the Internet, you will be trading your money and promises for a provider’s bandwidth and promises in return.

It pays to take a few moments to compare offers, shop, and, if necessary, walk away from a lame deal. Here are some questions to ask and some catch-22s to avoid. First, realize that the initial signup giveaways are predicated on the expectation that you will be a loyal customer for years.

If you are fickle and pick a competitor later, you may discover that you’ve agreed to pay back all those discounts. You may owe them a refund even if you have to move out of town because your company requires it.

Of course, if you don’t mind paying more, no-contract service is almost certainly available if you ask for it, and you may have to pay for installation and startup. Subscribers with contracts are worth more to an ISP, especially the ones that might be considering a merger or sellout.

If you can avoid the aforementioned penalties, changing to a new ISP is usually easy, assuming that the replacement uses the same DSL carrier. If not, it works as though you have completely shut your connection down and are rebuilding it from the beginning.

The Frequently Asked Questions apply to almost all prospective customers. Here are some other gotchas that are less general, but still worth considering.

Are their Fair Use prohibitions going to cramp your style?

Most providers have a list of prohibitions including obvious no-nos such as spamming the world, publishing pornography, libeling an organization, or preaching violent hatred.

These probably won’t apply to you, but the provider’s list can be so long or vague that they can dump you without an appeal for doing something you consider legitimate. If you are buying a high-speed link to solve a specific problem, such as a web site for my kids soccer team statistics, ask them about it.

Does Fair Use include forced traffic reduction?

Some providers, particularly satellite DSL providers, will automatically strangle your speed if you exceed their usage limit. The rules defining their trigger event and their throttle duration may be complex. In practice, they may also prove to be very inconvenient.

If they supply home networking equipment, then who is responsible for fixing or replacing it? If you are just going to be handed off to the manufacturer anyway, then you are probably better off shopping for it on your own.

What will the routing be from your home to the Internet?

If you’ve signed up with a national provider, your packets may have to cross state lines before they actually hit the Internet. That won’t decrease your speed, necessarily, but it will affect latency, which is very annoying to Internet game-players. And it may complicate troubleshooting.

If you plan to use your own built-in DSL or network interface, will it be compatible with their equipment and protocols?

Some PCs have interface equipment built in. You may want to use a cable modem you carried over from your previous residence. They may not work now.

Will additional interior or exterior wiring be necessary?

Usually, the answer is no, particularly for a Wi-Fi home network. But if your broadband link must terminate in a designated location, such as a computer room, you may have to pay someone to put it there.

Are their restrictions for my particular PC or operating system?

Pentium or clone-based PCs are universally accepted. But will the provider’s installation CD recognize a MAC, or a Linux, or a Unix, or something that’s not quite so standard?

How long does it take for service to be activated?

Rest assured, it will take longer than ordering a pizza. Whatever answer you do get will be a theoretical best case.