Analyze this

As WLANS (wireless LANs) evolve from departmental phenomenon to being part of the corporatewide infrastructure strategy, managers have to make IEEE 802.11x a complete member of the network family.

Companies offering protocol analyzers used in the wired network are now extending their products to WLANs. Major players include Finisar Corp., Network Associates Inc., Network Instruments, LLC and Wild Packets Inc. I spoke with Tom Gallatin, senior product manager, and John Mattes, technical support specialist, at Finisar in Sunnyvale, Calif.

This column cannot be a complete discussion of protocol analyzers, and if it was, I certainly would not be the one to lead it. So I'll just tell you about some important analytical features uniquely related to using WLANs.

Probably the most significant difference between wired and wireless analyzers is that the latter can be used as a first line of defense against unauthorized access.

For example, if an unknown MAC (Medium Access Control) address -- which moves packets around in a shared network -- comes in, the wireless analyzer identifies the address and sends an alert to the network manager. Of course the MAC layer can be spoofed, but as I said, it's the first line of defense. If someone tries to set up a rogue access point, again, an alert is sent.

The wireless analyzer can measure association attempts, and if a user tries to gain unauthorized access, it will monitor and log the attempt. Or, for example, let's say everyone in your company uses a Cisco wireless card in their laptop. If someone tries to access the network using an Intel card, you'll know about it.

Similar to their wired counterparts, wireless analyzers can perform a site survey to see how much traffic is on the network and over what channels. If one user is taking up a lot of bandwidth, someone might ask him or her, "What are you using it for?"

Analyzers can also be used to find dead zones in a wireless network prior to installation so that access points can be more efficiently deployed.

The goal of IT, of course, is to make the technology invisible to the end-user. By monitoring the network and finding its glitches, the network manager can compensate for poor quality and can help make network use appear seamless.

Finisar's Gallatin and Mattes say that the company's Surveyor Wireless has a number of benefits when compared with its competition. The software can support two separate wireless cards in a single laptop so that each card can be dedicated to a separate channel. It also offers multichannel views of all seven layers of packets and network traffic, from the physical layer to the application layer. Of course, it can use filters to focus in on any one layer as well.

Users can still use their laptop while the analyzer is running; it does not have to be a dedicated protocol analyzer. The point is, if your company is going to get serious about deploying WLANs, it pays to deploy a wireless protocol analyzer as part of the system.

Send me e-mail at

Join the newsletter!


Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.

More about FinisarIEEEIntelNetwork Associates InternationalNetwork InstrumentsSurveyor

Show Comments