electronic international standard serial number (EISSN)
In Polymorphous Optical Burst-Switched (POBS) networks, the Burst Control Packets (BCPs) of conventional Just-Enough-Time based signalling OBS networks are given extended properties which enable them not only to reserve fixedtime-slots for asynchronous data bursts, but also to allocate TDM reservations for periodic streams of data, and even a complete wavelength for high-bandwidth demanding services. This allows POBS to provide a flexible, yet transparent, approach for supporting the idiosyncrasies of today's most popular services overthe same underlying network architecture. In POBS, the spare gaps in between synchronous TDM reservations can be used for the allocation of best-effort data bursts, leading to a more efficient utilisation of the optical capacity.This work shows how to extend the well-known Erlang Fixed Point procedure to evaluate the performance behavior of POBS networks, whereby asynchronous data bursts coexist with highpriority periodic TDM reservations. The performance evaluation algorithm is applied to a number of case scenarios, showing thebenefits arisen due to the flexibility of POBS networks.