Thereare a variety of different modem speeds and communications standards, but the important thing to remember is this: nomatter how fast your modem is, you are also limited by the capability of the modem on the other end of the phone line.The two modems will "negotiate" until they find the highest speed and communications standard that they have incommon, and that is the upper limit of transmission speed that you'll get (a poor telephone-line connection can forcethe modems to reduce speed further until the transmission is reliable). To avoid on-line letdown, check out thecapabilities of your destinations before buying that hot new modem. Most Internet Service Providers (ISPs) have 28,800 bps modems, but on-line services such as CompuServe are restricted to 14,400 or even 9600 bps, depending on the area.

Any modem that you would consider would becalled a Hayes-compatible modem, because modem manufacturer Hayes originated the modem control codes that have becomethe norm in North America. Travelers look out, though‹standards differ around the world, and North American modems maynot work in foreign countries; check it out before you travel. Even in Canada, don't take for granted that you canplug into your hotel room phone jack. Many hotels and offices use digital PBX phone systems; you can quick-fry your modem simply by plugging it into a digital phone jack.(If the phone has more than a few buttons on it, or if you can activate different features by dialling particular numbers, then it is probably a digital set. Ask the hotel staff or office manager if analog lines are available in the room, and if not, whether there is a business courtesy line or aFAX line that you can use.

All else being equal, the bits per second (or bps, often incorrectly called the baudrate) determines the speed of transmission of data. Then, on top of the basic transmission rate, there are variousstandards for data compression (to squash your data down so more bits can be transmitted) and error correction (tomaintain a connection on less than perfect phone lines). Data compression standards, often referred to as MNP 5, V.42and/or V.42bis, are rated as giving as much as a four to one compression of your data, theoretically transferring 9600bits per second of data on a 2400 bps modem. However, this is an ideal case, and the amount your data can becompressed depends on the types of files it is stored in. If you have already used Stuffit or DiskDoubler to compressyour files for example, you won't get any real gains from the modem's compression, because the files can't be squeezedany smaller.

Beware of modem vendors who advertise their modems at the theoretical maximum (4X) transmission rate after data compression; when purchasing make sure that you are comparing modems of the same basic bps capability. Alsobe aware that some combination fax and data modems can have one speed for FAX transmission and a slower speed fordata, typically 9600 bps fax and 2400 bps data, so don't assume that the 9600 that you see advertised is actually 9600bps data. While you're at it, check that the modem can both send and receive FAXes, and that it comes with both FAXand data communications software for the Mac.

The slowest modems that you'll see today are 9600 bit per secondmodels. 9600 baud is adequate for browsing bulletin boards and using the Internet for EMail, but will be pretty slow for downloading(copying to your machine) files of any appreciable size. If this is all you need, buy a used modem from one of thehundreds of people who have upgraded to something faster. You can use the excellent shareware data communicationssoftware ZTerm with it, but make sure that you get a Macintosh modem cable - IBM cables won't work.

In the recentpast, 9600 bps (the V.32 standard) modems were popular; these seem to have been pushed aside by14,400 bps modems (the V.32bis standard) as the budget choice. The current crop of "fastest" modems are the 28,800 bps models, (the V.34 standard).If the services that you plan to use have installed 28.8 modems, downloading of files can be almost be twice as fast asthe next-best 14,400 modems. The fly in this ointment is that most modem manufacturers brought out newmodels in advance of the world standards committee finalizing the standards for 28,800 bps transmission. So we have19,200 bps "V.32terbo" modems and 28,800 bps "V.FC" or "V.Fast" modems, neither of which are compatible with the"V.34" standard. If you are serious about communications, or want a modem that you don't have to replace in the nextfew years, make sure that the modem that you are considering is a properproper V.34 model. Some manufacturers are offering no-charge user-installable upgrades to V.34 from their earlier V.FC models. The 19,200 bps V.32terbo modems cannot be upgraded to V.34, andseem to be consigned to a cul-de-sac in communications history. One modem that I am aware of, theUS Robotics Courier V.ANY modem supports all three standards simultaneously. This would be a good choice for BBS andEMail system operators but expensive for anyone else.

Almost all of these new modems are both FAX and data capable, and the mainreason to choose between one name-brand and another is the quality of the software bundled with the modem. You willneed data communications software to do anything, and if you are going to join the Internet, you will need additionalpieces of software, most of which are available as freeware.

For FAX software, some people really like GlobalVillage's GlobalFAX software, which only comes with the Global Village modems (good quality but pricey). Othersswear by FaxSTF, which is bundled by many manufacturers or available commercially for about $ 80. Delrina Fax Profor Macintosh v.1.5 is available for about $ 150 and is reputed to be very good. For data communications, some modemvendors bundle ZTerm (cheapskates!), QuickLink II is no longer produced, and I have heard lots of complaints about it. Microphone is apopular data communications package, the "LT" version is often bundled with modems and the Pro version is available separately. Be aware that the modem drivers and FAX software are continually being updated for better compatibility and to fix bugs. Owning a modem means keeping informed on these updates; look for a modem company that makes their updates available for downloading on the Internet, or from a BBS.

Modem name brands to look for areGlobal Village, Supra and US Robotics. All have models ranging from affordable to expensive. Motorola makes high speed, expensive modems for critical uses.

Hayes and Practical Peripherals are good products, but Hayes (who also owns Practical Peripherals) is currenly in bankruptcy and is looking for a buyer. I feel that Best Data, GVC, Prometheus and Zoom are a notch lower in quality than the first batch (althoughothers may disagree, I've had customers experience troubles with these). Joining the host of modems in the deadcomputing companies' graveyard are Abaton, Applied Engineering, Dove and Everex (and the original Apple Modem and PowerBookExpress modems). Avoid these brands unless you know that you will never need software upgrades or support. One other consideration among the better 28,800 bps modems is the presence of a "Flash ROM". Every modem has some programming inside it to make it work. The best modems have this program code in a Flash ROM chip which can be updated just by sending the new code to the modem from your computer. Modems without a Flash ROM can only have their ROM code updated by physically removing and replacing the ROM chip in the modem.

Cablesare important. Apart from having a Macintosh style cable (usually called a Mac-to-Hayes Modem cable), for 9600 bps andup modems, you also have to check that the cable is a "Hardware Handshaking, or "High-speed" modem cable. If it isn'tyou may not get a reliable connection, and you certainly won't reach the speed potential of the modem. These highspeed cables have a couple of extra wires connected which allow the computer and modem to communicate with each otherwhen they are ready to send or receive more data (the relevant pins are Mac pin 1 to Modem pins 4&20, and Mac pin 2 toModem pin 5. Mac pin 8 should also go to ground.)

When is a modem not a modem? When it's a GeoPort,Apple's multi-purpose communications connector on Quadra AV models and PowerMacs. The GeoPort doesn't have a modemcommunications chip in it, instead it relies on the processing power of the Quadra's AV DSP chip or the PowerMac'sPowerPC chip to do the grunt work. I'm not a big fan of this approach, because it forces the machine to divertcomputing power away from whatever else the machine is doing, potentially affecting the other processes, particularlyvideo and audio processing. Apple tried this method with the original PowerBook Express modems, which promised 14,400bps at unheard-of low prices‹it failed spectacularly. A regular modem can be moved from one Mac to another, theGeoPort can't, and a name brand modem is more likely to enjoy compatibility and support from most software packages.Apple's software for the GeoPort is rudimentary and has been buggy, forcing most people to buy extra software, andlast but not least, the GeoPort "pod" that you have to buy to hook up to the telephone line costs almost half as much as aproper modem. When Apple finally integrates digital PBX connection abilities into a GeoPort pod, I'll have anotherlook at it, but 'til then, I'll pass.

Consumer hint: It's generally not a good idea to buy the IBM-compatibleversion of a modem just because it's a bit cheaper. You will have the expense and trouble of finding a Mac modemcable, and you won't be getting the Macintosh FAX and data software that is almost always bundled with the Macintoshversion. Even if you have the FAX and modem software already, you won't be getting the modem driver files for your newmodem, and the software may not work as well as it should without the drivers. All in all, buy the Mac version‹you'llbe happier.

One last hint: new modems come with lots of glitzy offers to try out commercial on-line services suchas GENIE, America Online, Prodigy, CompuServe, Dow Jones and Delphi. They usually offer a package of free connecttime, but read the fine print! Almost always, there are hefty surcharges for calling from Canada, even on the "free"hours, and you may have to call long distance to connect to the service, paying your phone company's long distance rate on top. That said, the virtue of commercial on-line services is that they have collected and organized their content, so it's much easier to find information that on the Internet, which is gloriously unorganized. For my money,the best commercial on-line service for Canadians is CompuServe, but this depends on the content that you are lookingfor. For simply exchanging EMail however, signing up with a local Internet Service Provider is much cheaper.