How Fast Can You Go?

When was the last time you asked someone if they use the Internet? Chances are, not recently. At this point in the technology timeline, most of us just take it for granted that the majority of our friends and coworkers get online. Right now, the burning question surrounding the Internet concerns speed—the length of time it takes to connect to cyberspace.

In this article I will look at the most popular types of connection speeds available at home and in the office. These speeds fall into two distinct categories: analog (modem) and digital (high-speed broadband).

Analog modems utilize “Plain Old Telephone” (POTs) lines maintained by the phone company. Through hooking an analog modem up to the telephone company’s analog network, digital data can flow over the network by performing a digital-to-analog conversion for transmission onto the network. At the end of the transmission, the data is reconverted to digital. The only requirement for analog modems is that each end of the call must have a compatible modem.

Though considered the most standard form of data communications available, analog modem connections are limited by the telephone company’s voice bandwidth service. Current analog modems are struggling to achieve rates of only 56 Kbps. With a bandwidth of approximately 3,000 Hz, there is a finite limit on the amount of data that can be encoded and sent reliably through the network. Given the popularity of the Internet and the amount of information that is on even the most basic of web pages, most user needs far outpace the abilities of analog modems.

Integrated Services Digital Network (ISDN) is a telephone company technology provider that supplies digital service in increments usually of 64 Kbps channels. ISDN requires the phone company to install services within their phone switches to support the company’s digitally switched connection service. Though ISDN has been around for many years, its popularity is only now beginning to increase as the limitations of analog modems are becoming more apparent. The rollout of this service initially got off to a slow start with high costs, lack of standards and a low consumer acceptance rate interrupting the company’s momentum.

Digital Subscriber Lines (DSL) has two main categories, Asymmetric Digital Subscriber Line (ADSL) and Symmetric Digital Subscriber Line (SDSL); the technology is usually called xDSL when referring to all of the different types. Backed by the telephone company, this technology provides next high bandwidth services to the home and business using the existing telephone cabling infrastructure. DSL to the home runs over current POTs lines and has a bandwidth speed of up to 9 Mbps, but distance limitations and line quality conditions can prevent the connection from taking place at the top speed. DSL technologies use a greater range of frequencies over the cable than traditional telephone services. This allows for greater bandwidth to send and receive information. This technology is still in the early stages of rollout with standards and products just getting under way.

Cable modems are devices that attach to the cable TV network connection in your home. This broadband technology is driven by cable companies to provide services beyond traditional broadcast cable TV, such as Internet access. Along with xDSL, cable modems are still in the early stages of development. There are a number of challenges that face this industry, including return path capabilities and standards. However, potential bandwidth estimates range upwards of 30 Mbps from the service provider to subscriber.

Cable networks are inherently different in design from telephone networks. Cable networks are broadcast oriented, with each subscriber in an area receiving the same signals as all subscribers in the same area. xDSL is circuit oriented so that each connection is independent of all others. Cable networks are hierarchical in nature, thus requiring two paths: one for downstream and one for upstream. This requires either a second cable plant for upstream or a second frequency band allocated onto the existing system.

One of the more popular connections that businesses use to access the Internet is the T-1. A T-1 line actually consists of 24 individual channels, each of which supports transfer of 64 Kbps. A dedicated T-1 connection can support data rates of 1.544 Mbps. The T-1 connection can carry both data and voice transmissions over a single connection through configuring the line’s 64 Kbps channels.

There is also the T-3 connection that is considered the backbone of the Internet. The T-3 is analogous to a T-1 on steroids. Instead of the 24 channels per line with a transfer speed of 1.54 Mbps found in a T-1, a T-3 is capable of holding 672 channels per line with a transfer speed of 43 Mbps.

As you can see, there are many different connections to the Internet. If you spend as much time on the computer as I do, then the faster the better, I believe. I have a cable modem at home and the New York State Society of CPAs uses a full T-1 connection for both voice and data. Needless to say, I have grown accustomed to a fast connection and I could not imagine using a 56k modem at this point.

As you ponder the sort of connection that you want to have, it is important to ask yourself the following questions to determine if the benefits really outweigh the costs:

• Is the connection type that you want available in your area?
• How much are you prepared to spend each month on a connection?
• How much time do you spend surfing the Internet?

For more information, please contact NYSSCPA Chief Technology Officer Kevin Lewis at (212) 719-8340, (800) 633-6320, or klewis@nysscpa.org.