Defragmentation-as-a-Service (DaaS): How beneficial is it?
  We analyze Defragmentation-as-a-Service (DaaS) in elastic optical networks and show that the positive effect of defragmentation depends on the rate at which it is performed, load (or, call arrival rates) and the available resources. 
Sandeep Kumar Singh, Wolfgang Bziuk, and Admela Jukan
cs.NI