If you have dial-up ISDN from the telephone company, you know it can get expensive. In most areas, you pay for every second you're online because your telephone company charges you for usage. Cable modem-based Internet access is primarily a consumer service, offered almost exclusively in residential areas. Even if cable service is available to your business, you should be aware that cable service suffers from several technological flaws that make it an unacceptable solution for most businesses. Cable service is a shared connectivity medium much like a local area network, which means as more users are online, the connection slows down for everyone.
Cable service has serious security risks for computer connected to the cable network.
Because the cable network is Ethernet based within a given geographical area, other users can access your data. Cable service is restricted in terms of what you can and can't do with the service. The cable operator strictly controls your Internet service options to preclude your business from getting the most out of the service. For example, you can't use your own domain name, get multiple email boxes, or run your own Web server. With Speeds ranging from 384 Kbps to 1.5 Mbps, DSL brings all the promise of the Internet without the wait.