Do you remember all of those employees who brought home wireless LAN (WLAN) equipment and then started bringing their cards and access points into the workplace? If you thought that was a mess, get ready for Wave 2 - the Wi-Fi cell phone.

At the recent CTIA Wireless 2006 show in Las Vegas, Nokia and Samsung Mobile displayed mobile phones that included a Wi-Fi radio in addition to the normal wide-area wireless radio.

These vendors weren't the first to do this, but these models were the first ones geared to a consumer audience. The earlier devices were geared to enterprise customers who want to use Wi-Fi in an IT-controlled environment, such as a college campus or warehouse, as well as integrate with existing VoIP or PBX infrastructures.

The Nokia 6136 and Samsung T709 are geared to consumers. For example, the Samsung T709 lets calls channel from a Wi-Fi access point, through the Internet and onto a cellular network to give users uninterrupted connections when traveling between home and office or while on the road.

A phone that uses Wi-Fi and a cellular connection could mean trouble for network managers. Imagine this help desk query from the vice president of sales. "Yeah, I was making a cell phone call with my spankin' new cell phone, and I walked into a stairwell and the call dropped - I just lost the $100 million deal I was working on."

The vice president might not have realised that the call he was making connected via the internal Wi-Fi network instead of the regular cell network - all he knows is that the call dropped, and he may blame you

Just like they started asking for WLANs in the workplace, users will start asking for better WLAN coverage for voice applications. I discussed this issue with the head of the Wi-Fi Alliance at the CTIA show, and he admitted that most enterprise WLANs were designed for wireless data, not wireless voice.

He suggested that the best way for a company to find out where its wireless coverage holes are is to add Wi-Fi-enabled phones to the network and have people walk around the office and wait for the calls to drop.

Last year when Network World tested the ability for WLAN systems (enterprise switches and access points) to handle wireless VoIP traffic, the results were dismal. We hope that when we test these systems again later this year the numbers will improve.

At any rate, the clock is ticking for you to start improving your WLAN network before other vendors come out with their Wi-Fi cell phones and you're inundated with employees pounding your WLAN with voice traffic.