He cites the fact that Apple pioneered the implementation of gigabit Ethernet in notebooks, a practice that has since become the norm. Yet gigabit Ethernet was clearly an improvement on what went before. You can hardly say an 11n link is better in speed or reliability than wired gigabit Ethernet.

The issue of how you get a connection in a conference when everyone is trying to get online at once, compounding radio contention with lan contention, is only half of the matter. To use 11n instead of a wired lan is to change it from an edge technology to a distribution medium, encouraging the use of long-range relatively high-power wireless signals.

This is going to raise the noise level and drain batteries. Even on today's projected uses, it is not at all clear how well 11n would scale up to saturation adoption.

The fact that the industry is exploring UWB and 60GHz links to deliver HD video streams is testament to such doubts.

These alternatives have in common that they are short range, which allows high user density, reduces contention, and (crucial for mobile devices) is more power efficient.

Wifi is bad in all these respects. It is the radio equivalent of shouting across the playground rather than walking over and talking quietly to someone.

It does little or nothing to address the problem of radio pollution, which will only get worse as time goes on. On top of that, people are beginning to get concerned about possible health risks of using high-power Wifi notebooks at close range.

These fears may not be justified, but those who express them ought to be able to find common cause with engineers. It should surely be a general principle that radio data links should be as short as possible at the least power necessary. That argues for keeping taking the wired network as far as you can, and bringing on your whispering wireless for the last short hop.