Avoid surprises and stay a step ahead of end users

We’re in one of those periods of explosive expansion in the computer industry again. All sorts of new technologies are elbowing their way to the foreground. Problems arise when your users begin implementing these technologies before you’re ready to support them. Let’s take a brief look at what’s hot, what’s not and what to look out for.

— Cable modems. Businesses are starting to look at VPN over cable as an inexpensive way to connect local offices and home-based workers. My advice is to stay the heck away! Early adopters had a blast with this, as the fewer users a cable modem system has, the better it works. Now many metropolitan systems are at or beyond saturation, and performance is absurdly low, especially at peak times.

My organization recently measured connectivity via the main pipeline to our cable provider’s head-end equipment. This line is fibre-optic, so noise, interference or gremlins can’t account for the results. We were expecting about 3 Mbps, but we actually got only less than 200,000 bps. You’re better off looking at other high-speed, inexpensive solutions.

— XDSL. Three things seem to be consistently true about xDSL: system reliability is still a little shaky; what’s supposed to be an “always-on” connection isn’t and often needs special software; and when xDSL is working, it’s faster than blazes. Providers also swear that adding more users won’t degrade performance (but this assumes that they oversubscribe available bandwidth).

— Wireless offices. They work pretty well, given that the typical office is a noisy place, electrically. The secret is how fast 802.11b performance degrades under some circumstances. As you move away from the access point, 11Mbps becomes 5.5Mbps, then 3Mbps, then 2Mbps, then 1Mbps. Adding more users slows performance as well.

— Public wireless workspaces. Public spaces, such as airports, are wiring their facilities for 802.11b. Anyone who plunks down in the area and has a wireless adapter is automatically part of the neighbourhood. Some spaces charge, some don’t. Regardless of whether you’re paying for the privilege, you’ve just walked into espionage central. Wandering notebooks will need personal firewalls and dynamic VPNs at a minimum to safeguard data.

— Bluetooth. Everything I said about public wireless workspaces goes double here. Bluetooth is naturally “chatty,” so if one device senses another, they’ll have a nice long conversation about each other’s capabilities and resources.

The bad news is they “talk” to each other directly (no hub or other access point), so it can happen anywhere two or more Bluetooth-enabled devices come together. Espionage on the hoof, so to speak. Individual firewalls will be especially de rigueur when these devices become popular.

These problems can be overcome, in most cases with very little technology. The trick is to stay slightly ahead of your users. Make “no surprises” your motto.