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
Women may not be taking a common breast cancer drug due to the mistaken belief it causes nausea and vomiting, research suggests.
The two brothers were aged 10 and 11 when they tortured two boys in Edlington, south Yorkshire, in 2009 in a case that shocked Britain.
Anti-Islam politician Geert Wilders hit out at judges, saying he will "never be silenced" despite facing no punishment upon being convicted.