Fig 13.35 Optically formatted packet used for optical label swapping
Several methods have been examined in different network testbeds for creating and attaching a label to an optical packet and experiments have demonstrated label swapping at data rates of up to 40 and 160 Gb/s. The limitation of an OPS network is that the technology for creating practical optical buffers needs further development. Similar to other switching methodologies, these buffers are needed to store the optical packets temporarily during the time it takes to set up an output path though an intermediate optical packet switch and to resolve any port contentions that may arise between two or more incoming packets destined for the same output port. This technology can be circumvented though the optical burst switching concept described in the next section.