Is it OK to borrow someone else’s wireless network without their permission? And how do you stop others doing the same to you?

I am faced with a modern ethical conundrum. My flat is very long and thin and, frustratingly, my wireless network does not extend from the office at the back to the lounge at the front. My dreams of sofa-surfing have been thwarted. However, my laptop does pick up my neighbour’s Wi-Fi connection. It’s called “belkin54g” after the brand of router he is using. A quick Google reveals the default passwords for this router. A few security screens later, I’ve effortlessly hacked into my neighbour’s Wi-Fi. I can now surf on the sofa while watching TV and drinking red wine. Bliss.

Of course, he doesn’t know this, which leaves the conundrum: should I tell him his network is unprotected and risk losing my convenient living room wi-fi? Or should I continue to hijack his connection, risking discovery and a possible neighbourly feud?

Published in The Guardian April 23rd 05

I am sure I’m not alone in this situation. Increasing use of home wireless networks has led to a proliferation of free internet access hotspots in every neighbourhood. Wi-Fi uses radio frequencies to broadcast an internet connection in all directions. Depending on the thickness of walls and the quality of the aerial, the area can stretch up to the size of a football pitch.

There are now close to a million Wi-Fi users in the UK. according to research company IDC. About 50% are not running any security. In my south London street alone, wi-fi sniffer program MacStumbler (www.macstumbler.com) picks up seven connections. Only three are protected.

Tapping into a nearby hotspot takes a little luck and gymnastic ability. As with mobile phones, wi-fi is impeded by thick walls and metal. The signals travel better through glass, so sitting by a window or outside helps.

You can invest in a larger, better aerials to boost receptivity or you can opt for the hacker aerial of choice: the humble Pringles can (Google “wifi Pringles can” if you don’t believe me).

A bout of laptop semaphore in your area will probably bring up a selection of networks, usually named after big brands. Look for “Linksys”, “Apple Network” , “belkin54g” or “NETGEAR”. Networks with custom names like “fortknx” or “hax0rheaven” may indicate that tech-savvy killjoys have barricaded their domains. You’re unlikely to get into these. Networks with the default names however usually use default passwords. Try: “admin”, “1234″, “qwerty”, “password” - or “public”, if it’s Apple.

So is it legal to siphon bandwidth from open networks? The answer seems to be yes. There are no UK laws that specifically outlaw it - as long you as you don’t tamper with files or change settings. Then you could be contravening the Computer Misuse Act, or even be classed as a cyberterrorist under the Terrorism Act 2000. SWAT teams descending on your house in the middle of the night may get curtains twitching.

Socially, unwritten rules would suggest that piggybacking is OK. Wi-Fi is more than 20 times faster than broadband, so it can easily accommodate a few squatters. Email and browsing is unlikely to chip into your neighbour’s bandwidth. However, heavy file-sharing or downloading high-resolution Star Wars trailers will most likely get you off the Christmas card list.

I think I went a bit far. Heady with hackerly success, I soon found a way of logging directly into my neighbour’s router admin screen which he had failed to password protect. From there, I could have - if I wanted to - changed the login and locked him out of his own connection. If his security had been lax, or if he had shared folders, I could have gained access to personal data.

With this realisation came the paranoia that he would discover my indiscretions and come round with a bicycle chain to break my signal. So I knocked on his door and sheepishly came clean. He just laughed.

“I’ve been doing the same,” he said. “I can pick up your network at the back of the house.”

“Oh, really,” I said through gritted teeth, silently logging all the personal data he may or may not have rifled through. “How funny.”

We stood on the doorstep for a few minutes cussing technology. Then I went inside and changed all my passwords.

Better safe than sorry.

August 05 - Since I wrote this article, a man in the UK has been prosecuted for hijacking a wireless broadband connection. Details here. DM