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Spirent TestCenter: Does TestCenter utilize Port MTU size or other method to send and receive (disassemble and reassemble) fragment packets (fragmentation)?


Spirent TestCenter does not send and receive fragmented packets. 

TestCenter does not send packets to the Device Under Test (DUT) that will be fragmented by the DUT and expect to be able to receive and account for those packets on the receive port.
I explain this is because the signature field that is included in the packet and used to identify stream id and sequence number is not included in both part of the fragmented packets and can therefore be tracked.
I explain the Port MTU size is used for routing OSPF and ISIS ‘control plane’ packets (routing management packets for example routing updates packets) as most Routers DUTs  must have compatible MTU size to communicate. When the TestCenter port is configured as a Router port, this compatibility with the Router DUT is required on the TestCenter port and the DUT. This does not have any effect on ‘data plane’ traffic.  
I add Port MTU is also used to Fiber channel FCoE control plane and reference index entitled Why FIP Advertisement is not recognized by the FC_VN port of the Spirent TestCenter in 4.10?
I add you can send fragment packets from TestCenter. I provide you recommend you link to associated index entitled The right "fragment offset" value when send fragment with raw stream by STC.