Choosing *another* ISP

Let me discourage ISP hopping for improved download speeds. There are very isolated conditions for improving the capacity of dialup connection by choice of ISP.

Dialup is dialup, and the capacity of dialup connection is a function of line (and signal) quality and how terminal equipments are appointed. Let me clear the air about quality before trying to explain configuration.

Line and signal quality for human communication is much less demanding than for data communication. The slightest echo on a telephone line will slow modem dialog to 33,600 bps. 33,600 bps, by the way, is the limit of how fast you can uplink data with dialup -- while an ideal circuit, in the United States, is capped by the FCC at 52,000 bps for downlink.

An analog telephone facility is limited to 2400 baud which is not the same as the 33,600 bps uplink and 52,000 bps downlink capacity. The 2400 baud capacity represents the number of state changes that facility can support. The higher than "baud" bps is accomplished with technical magic like compression, PCM, FSK, and QAM; but these are material for true geek discussion. What those forms of magic mean to end users is that line interferences of noise, induction, and capacitance make difficult the ability for computers to "hear" each other ... so the computers at each end negotiate a best "speaking" rate.

What things degrade line (and signal) quality? First, the price of telephones impacts line quality in the home. When more phones are installed on the computer's telephone circuit, more induction is added by the ringer equivalence of each telephone. Old, deteriorating wiring introduces voltage paths across the telephone line and to ground; this causes pops and clicks that are often audible to the human ear (but not necessarily). Oxidized connections introduce resistance into the loop; this reduces the effective signal (or baud) range.

Fortunately, conditions in the previous paragraph are easily repaired. New wiring for a typical home is not expensive and replacement does not require any great technical skill. Just make a home run from the computer line connection to the telco interface and another run from the computer phone connection to bridge any telephones sharing the line. This configuration will eliminate competition and interference from phones and lines which must not be in use while a computer is online.

Next, line quality can be impacted by the telephone company facility. All line noise that remains after customer premise wiring and equipment is removed from the telco interface is the responsibility of the telco. Telcos do not want subscribers to know this, but their "warranty of voice quality service" is bogus. Don't let their noise to that effect prevent call after call after call to their service centers and the Public Utility Commision ... and every call should be made with information of dates, times, and correspondents in *any* conversation made regarding line quality. Rate increases are based on customer service indices (these are under subscriber control).

An inescapable mitigator of line (and signal) quality is the number of analog to digital (and digital to analog) conversions in the loop. Don't expect greater than 33,600 bps when the ISP does not have a digital connection with the telco. This is one situation where changing ISP might be helpful, but it is a rare ISP not using an upstream aggregator for their modem pool (AOL does this, Earthlink does this ... and so do I) -- telco ISP like Sprint, BellSouth, Verizon, and even the Gadsden Alabama Co-Op are (by necessity) digitally connected with the communication grid.

With line quality issues under control, terminal configuration can be improved. Modems degrade; if a modem is more than a year or two old, a new ($19.95) modem may be just the fix for poor connection rates. Mismatched UART/digital signaling rates can impact modem throughput; try setting line speed to 56,600 bps instead of driving the UART and buffer at 115,000 bps (or more). Registry bloat can mitigate modem performance; I have improved more than one computer by removing artifacts of old ISP and uninstalled softwares.

I only hope this helps prevent unnecessary time invested in finding the "right" ISP.