BBC security correspondent Frank Gardner answers some of the key questions posed by the case of Dhiren Barot.
Why is the case so significant?
He is interesting because he is like a link between old al-Qaeda and the new kind of global jihadi movement.
He was somebody who was radicalised right back in the 1990s, over 10 years ago.
He started going to training camps in Kashmir and in the Philippines. He learned counter-surveillance, he learnt demolitions - firing weapons as many people did. But he learned far more sophisticated terrorism methods than that.
And he presented his plans to the people who are believed to be associates of al-Qaeda - or even members of al-Qaeda - in Pakistan as recently as early 2004. So after 9/11.
Remember that after 9/11 al-Qaeda kind of fragmented - they lost their bases in Afghanistan, they scattered, many of them went to different countries - they were on the run.
But he belongs to both before that period and after that period.
So he is a pretty worrying phenomenon in that case and that's why they're so pleased that they've got this guy.
There were some high profile targets but how far had the planning actually gone?
The prosecution believed that he was in the final stages.
They believed that Dhiren Barot was very close to executing this attack.
Some people questioned how he can get such a heavy sentence when the explosives weren't actually found and it's not hard and fast proof that he actually had the funding in place.
But the overwhelming evidence that he's been convicted on is what's been found on hard drives of computers - often deleted files.
He was very good at trying to cover his tracks, for example, footage that he took in the United States was inserted, spliced between two parts of a Bruce Willis Die Hard video.
So he knew that there were people who were probably going to be looking for this stuff.
The Pakistani authorities co-operated a lot. Material was taken in Pakistan; code words were broken and found.
When the arrests were made in this country in August 2004, the police had just two weeks in which to hold Dhiren Barot and charge him.
So the computer experts were frantically going through these hard drives, working 24/7 - round the clock, trying to find enough evidence to actually bring charges and make them stick and it is an absolutely eleventh hour thing - they nearly ran out of time.
Frank Gardner was talking to BBC News 24