Modems

...28.8 or 33.6 kbps (V.34) modems, under ideal phone line conditions, will transmit and receive data at 28,800 or 33,600 bits per second, and 56K (X2, K56, or V.90 modems) will typically transmit data at up to 33.6 kbps, and receive data at up to about 50,000 kbps (more or less). Because all of these modems can use data compression, they can achieve throughputs of 2 or more times those rates on compressible files... >>>

...You probably know that modems are analog devices. You may not know, however, the telephone system in the US is a mix of analog and digital. Almost all calls in US are converted from analog to digital at your local phone company office, and stay digital until they reach the local loop of the place you call. So what is going on is we start with digital data at our computer, convert it to analog in our modem, and send it out to the phone system. The phone company switches it back to digital and transmits it, then converts it back to analog for the local loop at the other end. There, the modem converts it from analog back to digital for the remote computer... >>>

...The latest modem standard is V.92, which was determined by the ITU (International Telecommunications Union) at the end of 2000. Modems using this standard are still 56K modems, but three new features have been added -- faster connections, better uploading, and, data and voice support... >>>

..."Software Modems" (or "Soft Modems" as they are sometimes called) are modems which transfer many or most of the modem functions to software which uses your PC's CPU rather than performing them within the modem itself. This allows the manufacturer to produce a modem with very few parts on it (a HSP modem is little more than a host interface card and an associated modem software program), which greatly reduces their cost. It also allows some modem upgrades via software downloads rather than requiring firmware upgrades. In the early days of this type of modem, many users experienced substantial problems... >>>

...Over the last couple of years there has been lots of talk about cable modems -- modems that would hook to your TV cable, and let you get very high speed internet access. Availability is still limited in many areas, but is growing rapidly. Serious bandwidth problems would be experienced by most cable companies if they brought cable modems into wide use too rapidly which is one of the reasons implementation has not been fast. Some of the big cable companies are starting to use digital technologies that would partially address that problem. Some users of cable modems have complained that their access speeds have dropped by a factor of 4 or more as more customers sign up for the service... >>>

...DSL stands for Digital Subscriber Line, a service being provided by some telephone companies, with support by some ISPs. It provides normal voice service plus simultaneous Internet access at speeds up to 1.5 Mbps (or considerably higher in some cases) using a relatively new technology that runs over standard phone lines. While a couple of years ago it appeared that ISDN would be the next generation of technology that individuals would use for higher-speed access over phone lines, now it is clear that DSL is the favored technology for consumer service due to the fairly low implementation cost... >>>