Making sense of 56K modems

Archived Articles, General

Question: I have a USR 28.8 modem and would like to upgrade to a faster modem, because I’m sick of waiting for images to download and video taking forever. I’ve heard about K56Flex and X2. Can you explain them and tell me what I have to watch for? Should I bother with any of this or just buy a 33.6 modem? – S.P.

Answer: In the past, the Number 1 rule for modem technology was that the higher the speed number on the packaging, the faster it would go. Now, the modem makers are mixing letters with numbers – X2 and K56Flex. There’s also a whole species of high-speed technologies that are starting to trickle down the consumer pipeline like ADSL, ISDN, and cable modems. They’re guaranteed to give you a nosebleed because they’re so exciting.

Modem speed is still measured in bits per second or baud, but distilling the latest technologies takes some work. Here’s a quick explanation:

  • There are eight bits in a byte.
  • A typical run-of-the-mill ASCII character is one byte in size.
  • At 28,800 bps (or baud), 3,600 characters would be transmitted into or out of your computer via your modem in one second. That’s just over 400 words, with spaces – about the size of your average 10-item breakfast menu.

Of course with a 28,800 bps modem, you’ll never connect at full speed. That’s your first “if-but”. It’s more likely you’ll get online at somewhere between 21,000 bps and 26,000 bps. A 33.6Kbps modem will likely connect at a similarly diminished rate.

“You only get a true 33.6K bps connection about 10 per cent of the time while you’re connected,” explained Darren Schotte of Campus Computers in Edmonton. “Your actual connection to the internet changes continually while you’re online. The connection is not consistent because line noise will slow down data transfers.”

Here’s another “if-but”: The K56Flex and X2 standards both move data faster than 50K bps but, like the slower technologies, they fall short of actually advertised speeds. In fact, the near-56K baud transfer speeds can only be expected during downloads. So, data coming into your machine might move near the advertised speed, but the outbound data from you to the internet moves at a top speed of either 28.8 or 33.6. That’s OK if you’re only surfing, because outbound data is usually a small text request to a remote server.

Another problem? To use the technology, your Internet Service Provider has to support the protocol. If they don’t, your $250 investment will only connect as high as 33.6Kbps. You see, K56Flex and X2 are about as different as ham and pork … they’re mostly the same thing, but they come from different parts of the pig. And in this case, they’re different enough to be incompatible. X2 is from U.S. Robotics. K56Flex is from Rockwell International and Lucent Technologies. As a result, modem manufacturers have integrated one or the other into their products, and ISPs have to pick sides, as well.

Some ISPs are holding out entirely to see which side wins the war. A member of that group is Telus Communications. “There are a lot of concerns (about the two technologies) at this time,” said Peter Wong, Webmaster and Client Software Manager at Telus Planet Internet Service, in an e-mail. “First is that many of the tests indicate that the technology of ultra-high-speed are more promise than reality.” By this, he means next-generation technologies such as ADSL are just around the mainstream corner. It’s a new phone company technology that promises download speeds of up to two million bps.

Wong is also skeptical of the success rate of the two new protocols. “Computer trade magazines have been unable to achieve the speeds promised by the technology. They’re getting speeds that are faster than a 33.6 modem, but nowhere near the advertised speeds. This concerns us in terms of service expectations from our customers.”

Neither of the 56K schemes are currently recognized by the International Telecommunications Union, a standard-setting body. Both have been submitted for consideration. The likelihood is that the final scheme will probably incorporate features of both.

And don’t think a direct modem-to-modem connection with your Doom buddy will allow a nice clean 56K bps connection. The key to the technology is a digital data link at the ISP end. X2 and K56Flex modems are priced at about $250 to $300. You may also be able to upgrade your current modem (if it’s 28.8 or 33.6) to one of the two new protocols anywhere from free to $100. Check with the modem manufacturer for details.