Umar Arshad, 24, was jailed for six years and nine months and Syed Farhan Hussain, 22, for five years and three months for their roles in preparing for the terrorist attack at a Territorial Army centre.
The men, all from Luton, admitted one count of engaging in conduct in preparation for acts of terrorism between January 1 2011 and April 25 2012 at a hearing on March 1.
The men were arrested following a series of raids at their homes in April last year after an intelligence-led joint operation by the Metropolitan Police Counter Terrorism Command and the British Security Service (BSS).
More top news
The 'sugar tax' outlined in Chancellor George Osborne's March budget will "hit the poor the hardest", critics claim.
A woman who was "dragged away" by a crocodile as her friend tried in vain to rescue her is reportedly still missing in Australia.
Police say at least one gunman armed with a high-powered rifle, began "shooting randomly" resulting in the death of a man in his 50s.