Things to look for in a wireless router

It’s the time of year that a lot of people buy computer equipment, and wireless networking is one of the things people look for. But what things should be on the shopping list?

I was hoping you’d ask that question.Compatibility with what you already have, if possible. Routers are available that speak 802.11a, 802.11b, and 802.11g, or all three. If you already have some wireless equipment, look for something that can speak its language.

Cordless phone interference. 2.4 GHz cordless phones will interfere with 802.11b and 802.11g. 802.11a works at a different frequency, but it might be cheaper to replace your 2.4 GHz phone with a 900 MHz phone.

Speed. 802.11a and 802.11g operate at 54 Mbps, which is considerably nicer than 802.11b’s 11 Mbps, although both are much faster than current U.S. broadband connections, which tend to top out around 3 Mbps. If you move a lot of files around, you’ll appreciate the 54 Mbps speed. If your primary use of wireless is sharing an Internet connection and a printer or two, 802.11b is probably fast enough, and it’s usually cheaper, with the downside of shorter life expectancy.

802.11g is currently the most popular standard, because it gives 54 Mbps speed and offers compatibility with existing 802.11b equipment. Use this information as you will. If you’re of the security by obscurity mindset, 802.11a is a better choice, as a wardriver is more likely to be driving around with an 802.11b or 802.11g card. If you want to make sure your buddies can hook up when they come over, or you can hook up at your buddies’ places, 802.11g is the better choice.

Brand. Match the brands of router and cards, if at all possible. This makes configuration and security much simpler.

WPA. The encryption used by older standards is relatively weak. You want to enable 128-bit WEP (256-bit WEP is better but still not as good as WPA), change the SSID and disable SSID broadcast, and hard-code your MAC addresses so that only your cards can use your router. This protects you from someone driving around your neighborhood with a laptop and using your Internet connection to send out spam or transfer illicit material that can be traced back to you. Do you want the RIAA suing you because someone used your Internet connection to download 400 gigs’ worth of boy-band MP3s off Kazaa? Worse yet, if that happens, word might get out that you like that stuff.

WPA adds another layer of protection on top of these (which are standard issue by now). Rather than the security key being fixed, it’s dynamically generated from trillions of possibilities. Sufficient CPU power to crack WPA and either monitor your transmissions or use your access point might someday exist, but for now it gives the best protection available, so you should get it and use it. This USRobotics whitepaper on security ought to be a must-read.

Built-in firewall with port forwarding. This is a standard feature on all brand-name units and ought to be on the off brands as well, but it doesn’t hurt to double check. Hardware firewalls are far superior to software firewalls–they don’t annoy you with popups and they can’t be disabled by a malicious process. Port forwarding is necessary for a lot of games, and also if you want to run your own mail or web server.

Hackability. By this I don’t mean the ability of an outsider to get in, I mean your ability to add capability to it. The Linksys WRT54G is based on Linux, so it has a big following with an underground community adding capabilities to it all the time. If you want to take advantage of this, look for a WRT54G or another device with a similar following.

Network infrastructure for a small office

We talked earlier this week about servers, and undoubtedly some more questions will come up, but let’s go ahead and talk about small-office network infrastructure.
Cable and DSL modems are affordable enough that any small office within the service area of either ought to get one. For the cost of three dialup accounts, you can have Internet service that’s fast enough to be worth having.

I’ve talked a lot about sharing a broadband connection with Freesco, and while I like Freesco, in an office environment I recommend you get an appliance such as those offered by Linksys, US Robotics, D-Link, Netgear, Siemens, and a host of other companies. There are several simple reasons for this: The devices take up less space, they run cooler, there’s no need to wait for them to boot up in case of power failure or someone accidentally unplugging it, and being solid state, theoretically they’re more reliable than a recycled Pentium-75. Plus, they’re very fast and easy to set up (we’re talking five minutes in most cases) and very cheap–under $50. When I just checked, CompUSA’s house brand router/switch was running $39. It’s hard to find a 5-port switch for much less than that. Since you’ll probably use those switch ports for something anyway, the $10-$20 extra you pay to get broadband connection sharing and a DHCP server is more than worth your time.

My boss swears that when he replaced his Linksys combo router/100-megabit switch with a much pricier Cisco combo router/10-megabit switch, the Cisco was faster, not only upstream, but also on the local network. I don’t doubt it, but you can’t buy Cisco gear at the local office supply store for $49.

For my money, I’d prefer to get a 24-port 3Com or Intel switch and plug it into a broadband sharing device but you’ll pay a lot more for commercial-grade 3Com or Intel gear. The cheap smallish switches you’ll see in the ads in the Sunday papers will work OK, but their reliability won’t be as high. Keep a spare on hand if you get the cheap stuff.

What about wireless? Wireless can save you lots of time and money by not having to run CAT5 all over the place–assuming your building isn’t already wired–and your laptop users will love having a network connection anywhere they go. But security is an issue. At the very least, change your SSID from the factory default, turn on WEP (check your manual if it isn’t obvious how to do it), and hard-code your access point(s) to only accept the MAC addresses of the cards your company owns (again, check your manual). Even that isn’t enough necessarily to keep a determined wardriver out of your network. Cisco does the best job of providing decent security, but, again, you can’t buy Cisco gear at your local Staples. Also, to make it easier on yourself, make sure your first access point and your first couple of cards are the same brand. With some work, the variety pack will usually work together. Like-branded stuff always will. When you’re doing your initial setup, you want the first few steps to go as smoothly as possible.

I’d go so far as to turn off DHCP on the wireless segment. Most wardrivers probably have the ability to figure out your network topology, gateway, and know some DNSs. But why make life easier for them? Some won’t know how to do that, and that’ll keep them out. The sophisticated wardriver may decide it’s too much trouble and go find a friendlier network.

Why worry about wireless security? A wardriver may or may not be interested in your LAN. But that’s one concern. And while I don’t care if someone mooches some bandwidth off my LAN to go read USA Today, and I’d only be slightly annoyed if he used it to go download the newest version of Debian, I do care if someone uses my wireless network to send spam to 250,000 of his closest friends, or if he uses my wireless network to visit a bunch of child porn or warez sites.

Enough about that. Let’s talk about how to wire everything. First off, if you use a switched 100-megabit network, you can just wire everything together and not give much thought to anything. But if you’re using hubs or wireless to connect your desktops, be sure to put your servers on 100-megabit switch ports. The servers can then talk to each other at full speed if and when that’s necessary. And a switch port allows them to talk at full speed to a number of slower desktop PCs at once. The speed difference can be noticable.

More wireless networking

Well, I took the plunge. What good is credit when you don’t use it, right? I didn’t want to run CAT5 Ethernet cable everywhere and I didn’t want to spend hours playing with Linux drivers for phone-line networks that have been in beta for a year. Especially not with what few Usenet posts mention those drivers also mentioning kernel panics. No thanks.
Dan Bowman pointed out that JustDeals had good prices available on wireless gear. So I picked up a plain-old access point for $70 (I don’t want a combo access point/router/switch because I want something I can turn off when I’m not using it–can’t beat that for security) and a PCMCIA NIC for $29 and a pair of USB NICs for $29. That’ll let me put a computer in the front room and a computer in the spare room and it’ll let me wander around with my work laptop.

Dirt-cheap prices, no rebate hassles. Gotta love it. CompUSA’s prices on Netgear kit are good, but there are rebates involved, which is always a pain.

My plan for security, besides powering off the access point when I’m not using it, is to turn off DHCP, hard-code it to my NICs, turn on 128-bit WEP, use obnoxious passphrases, and place the access point as far from the outside wall as possible. That should give me acceptable security, especially considering the physical location of my house. Neither of my next-door neighbors has a wireless LAN, and I seriously doubt the neighbors behind me do either, and they’re pretty far back and might even be out of range anyway. I’m at the end of a street deep in a residential area, so most wardrivers probably won’t bother. And if they do, I’ll be home and I’ll probably see them.

One thing I learned today, which reveals my ignorance yesterday, is that most wireless NICs accept the “Any” parameter that we used to get a Linksys NIC talking with a 3Com access point so we could configure it. But your documentation may or may not mention it.

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