Triple-Play Service Deployment

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Chapter 6: Troubleshooting Video in the Headend
transport stream was affected by IP layer impairments, technicians
must have test visibility to the MPEG transport protocol, and it
must be real-time and simultaneous. Ideally this will include the
ability to perform simultaneous cross-layer analysis of both IP and
MPEG transport protocols to enable correlation of impairments at
both layers. Figure 6.12 below illustrates such a simultaneous
cross-layer analysis, as provided in the JDSU DTS-330 analyzer.
Figure 6.12 The Simultrack analysis offered in the DTS-330 MPEG analyzer tracks the MPEG
transport while in the Gigabit Ethernet pipe, monitoring IP performance parameters like inter
frame spacing as well as MPEG parameters like continuity counter errors.
The IP flows in the Gigabit Ethernet pipe are listed at the top.
Because this is a video over IP application, each flow in the list is an
MPEG MPTS or MPEG SPTS. Each entry includes an indication of
the Inter-Frame Delay (IP jitter) experienced on that flow, as well as
several Priority 1 MPEG measurements including continuity
counter, transport and PAT errors. The bottom window lists the
PIDs of the highlighted MPEG transport stream, with current
continuity counter errors and bit-rate listed per PID. With this
analysis, the technician can immediately assess if there has been
any negative impact to the MPEG transport streams during IP
transport, and rapidly identify not only which MPEG transport
streams suffered a packet loss from IP impairments, but also which
element of those MPEG programs was impacted.