Guest Author - Cathy Spearmon

If you have a choice between the two, then you’re the lucky one. Many of us don’t have the luxury of choosing either service. And some of us don’t even have the service available to us at all. But, if you do have both available, let’s take a look at the technologies behind each. When making that choice, you want to make sure that you’re confident with your decision.

There’s no doubt that high-speed Internet access is absolutely the best thing to happento the Web. DSL and cable modems have made those speedy connections possible. But, there are some differences and similarities between the two. There are major differences: Setup, Availability and Performance. While, there are also three major similarities between a cable modem and a DSL: Speed, Cost, Benefits and Security.

Differences

Setup
DSL (Digital Subscriber Link), a souped-up copper wire, uses the same telephone wiring as analog modems. However, it works on the unused (high) frequencies of the line. DSL modems, actually the heart of the DSL technology, contain an internal signal splitter that carries voice signals on usual low frequencies and data signals above that. The splitter allows simultaneous access to the link by telephone and computer. Computer users who might have originally been required to install a second phone line won’t have to with DSL service.

The cable modem, an external device, consists of two connectors, one to the cable wall outlet and the other to standard 10 Base-T Ethernet card in the PC. More specifically, cable companies dedicate a standard cable-TV channel to data transfer for Internet and multimedia services. PCs equipped with a cable modem are connected to the cable TV network using the same type of hookup used for the television. Once connected, the cable modem lines are set-aside for data transfer to access the Internet and multimedia services. The cable modem receives digital information carried over the cable TV network and passes it through the PC.

Availability
While most local cable companies offer cable modem service, the technology used to implement DSL service only works over limited physical distance. At a maximum, DSL runs about 18,000 feet (3.5 miles or 5.5 kilometers) from the telephone exchange. Historically, companies within the United States did not install public exchanges this close to homes in some suburban and rural areas. Some variations of the DSL technology constrain this physical cable distances even further, almost as low as 1,000 feet (.02 miles or .35 kilometers) in order to offer faster speeds.

Performance
Theoretically, cable modems are faster than DSL because cable television networks are designed to display full-motion pictures, which require greater bandwidth. This delivers Internet connection at very high speeds.
However, because of their network topology cable modems are at a distinct disadvantage. Cable modems use shared access to the system, like that of an office network, where all traffic in a particular area travels across a common connection. This shared access makes cable modem speeds comparable to DSLs. With the increased popularity of the service, speed sometimes slow to a virtual crawl.

DSL modems provide a dedicated connection to the phone company’s central office, but then share a single pipe from that central pipe to the Internet itself. The major complaint from consumers, regarding their DSL service performance, is that connections drop unexpectedly. Though cable modems offer better throughput, it varies. However, DSL service maintains a constant feed with lower latency.

Similarities

Speed
Both cable modem and DSL offer up to 100x more network performance than a standard modem. Either service loads Web pages instantly and downloads a typical MP3 file in a matter of a couple minutes.

Cost
Both services cost about the same ($40 to $60, including software, unlimited Internet access, specialized content, and modem rental) and require installation and connection fees. However, most companies are waiving these fees as an incentive to sign up for their service.

Benefits

The benefits of having a cable modem or DSL service are numerous. Once you experience either service, you’ll never want to go back to a standard modem. With either service, you have a constant connection to the Internet, unless you turn off your computer. There is no need to dial up and wait for a connection, to have a second telephone line installed, or worry about callers receiving a busy signal. Connectivity is fast and reliable.

Security
Cable modem and DSL service are no more, or less secure than any type of Internet connection. However, because you are constantly connected most of the time, you are more vulnerable to attacks. Installing a personal firewall would help protect against external attacks.

If you are in the position where you can choose between DSL and cable modem, the decision is not an easy task and the answers are not simple. Remember there are many factors that you need to take in account before committing to a service. The following are 10 questions that you should ask before you buy. If you do a little research and find out exactly what’s available to do you, you’ll be able to make the correct decision in whether cable modem or DSL is right for you and your needs.