service tax on sub rent received

will service tax will be levied on sub-rent received?

for eg. ABC co takes a building on rent basis and partly sub let out to other co.will sub rent received by ABC co will be chargeble to service tax. on what amount service tax will be levied i.e. on net rent ( Rent Receivde-Rent Paid) or Gross Rent Received.

if yes,are there any abetments or deduction allowed?