tmnxTestHdPayLd are bitmap for the frame payloads to be used for the test run, it is an optional parameter to be supplied along with tmnxTestHdAdminStatus when the test is started. Every 8 bits represents a payload. For this release, we support up to 4 payloads per test session. So only 32 bits will be used. With each 8 bits, one bit will be set to represent the payload indexes used for the payload. e.g 0x020104 means payload 3,1 and 2 are used.