VeEX VePAL TX300M, User Manual

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The TX300/e Fibre Channel option addresses all the transport layers by measuring the optical power level and supporting the
generation/analysis of bit errors, order sets, frame delimiters, frame transmission, and the generation of primitive sequences. User
defined bytes, fixed test patterns or industry-standard PRBS patterns can be selected and inserted into the payload field depending on
the test layer. Bit error, CRC error and Code violation insertion are useful features to verify Mux/Demux equipment for error monitoring
and detection.
Buffer-to-Buffer Credit Estimation
- To avoid loss of frames during transmission, the Fibre Channel protocol uses a buffer-to-buffer
flow control mechanism between link partners. During the login process, the remote node informs the local nodes as to the number of
receive buffers it has available. For each frame received, the remote port returns a R_RDY frame to indicate that one of the receive
buffers is now free - the local port in turn increments its available credit counter by one for each R_RDY acknowledgement frame it
receives. However, as the distance between nodes or link partners increases, so does the time it takes for the transmitting node to
receive the R_RDY frame because of signal propagation delay. The standard practice for a 1Gbps Fibre Channel link is to allow 1
buffer credit for each 2km of distance.
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16.1 Setup
16.1.1 Test Interfaces
The Fiber Channel test applications are specific to the fiber test ports or interfaces only.
SFP Transceivers
Support 1Gbps, 2Gbps, and 4Gbps test rates
850nm or 1310nm wavelength operation
XFP Transceivers
Support 8Gbps and 10Gbps test rates
850nm or 1310nm wavelength operation
“Fibre Channel ” versus “Fiber Channel”
TX300S_e-manual_D07-00-064P_RevA00