The roadside bomb is a popular weapon for insurgents battling a superior military force -- and perhaps Canada's deadliest foe in Afghanistan.

Around 1,500 bombs have been detonated this year alone. The military calls them improvised explosive devices, or IEDs.

Regardless of the name, they are responsible for about half of Canada's military deaths there - even though Ottawa and its allies have spent an estimated $13 billion in recent years to stop the carnage.

IEDs are the number one risk for Canadian troops serving in southern Afghanistan - including the latest rotation from CFB Petawawa.

The base's last deployment was in 2006, a pivotal time in the war to defeat the Taliban.

Canadian troops were victorious in face-to-face battle during Operation Medusa. The Taliban switched tactics, adopting IEDs as their preferred weapon.

The military established a counter-IED task force at Department of National Defence headquarters in the spring of 2007 under the command of Col. Omer Lavoie.

Lavoie lost his most senior officer to a roadside bomb while in Afghanistan as field commander during Operation Medusa.

"The key point for a commander is to see the change and to do something about it," he told CTV Ottawa.

The Kandahar unit operates like a fire department: put out a blaze and then investigate it. Soldiers have dubbed it "CSI: Kandahar." Col. Lavoie receives a daily briefing on the latest IED incidents in his Ottawa office.

Maj. Max Messier, who recently returned from the task force's Kandahar unit that investigates incidents and trains troops, said: "Yes we're making progress, we are doing a better job of training and understanding IEDs and tactics, but we are dealing with the uncertainties of Afghanistan."

To combat those uncertainties, the Canadian military has also upped the training given to troops back home. Two research centres are being established at CFG Gagetown, N.B., and more training is provided upon arrival in Afghanistan.

Private contractors, meanwhile, supply the military with all manner of devices to fight IEDs.

Allen-Vanguard of Ottawa produces robots, bomb suits, and electronic jamming equipment to stop triggering devices. CEO David Luxton called it a sophisticated high-tech battle of cat and mouse being fought in conflicts around the world.

"There's no silver bullet that will solve this problem," said Luxton.

"You have to bring to bear a great deal of tactics and intelligence, human and electronic intelligence, and forensics. It has become quite a sophisticated business."

The reality is that roadside hit their targets about 50 per cent of the time.

"There's always a fear in the back of your mind," said Master Cpl. Scott Bernelli.

"But at the end of the day you've got to do your job over there, and put it in the back of your mind so you get home safe and sound."

With a report from CTV Ottawa's Paul Brent