VIAVI TestCenter: What is the breakdown of the 16-bytes captured with using "Signature Mode?"
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VIAVI TestCenter: What is the breakdown of the 16-bytes captured with using "Signature Mode?"
When you open up the capture in Wireshark, its dissectors will try to decode it like a really messed up Ethernet frame. But since all that is captured is the first 16 bytes of the STC Signature Field here is a breakdown of what the bytes/bits decode into:
df 00018000 793b86c47920 3afb71f51 d
| | | | |
| | | | +-- 1101
| | | | | |+--- last
| | | | | +---- PRBS fill (1=yes)
| | | | +------ last two bits of the transmit timestamp ticks
| | | +-------------------- transmit timestamp ticks
| | +--------------------------------- sequence number
| +------------------------------------------ stream id
+--------------------------------------------- inverse of sequence byte 0 (the least significant byte in this case 0x20)