Verilink WANsuite 6450, Reference Manual

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V T 1 0 0 I n t e r f a c e 4-37
Figure 4.34 CES Service Details Screen
From this screen, you can access and change the parameters listed below. The
new parameters are saved when you “ESC” from the screen and perform a
Save and Restart.
VPI Determines VPI used for this CES Internet Working Function (IWF). The
default is 0.
VCI Determines VCI used for this CES IWF. The default is 33.
Service Type Determines if T1/E1 service is structured (Nx64 kbps with or without
signaling) or unstructured (2.048 Mbps or 1.544 Mbps raw data stream). You
must configure the Service Type to correspond with the desired CBR port
framing and channel rate in accordance with the table on page 4-40.
Timing Determines the CES services clocking mode, which maps to the transmit
clock source of the CBR interface and Serial interface (if configured for a
CES service). When “Adaptive” timing is selected, the receive AAL1 payload
buffer is monitored for predetermined threshold levels to control the
frequency of the interface clocks. When the buffer depth exceeds the
predetermined upper threshold, the interface clock frequency is increased to
cause the buffer to drain more quickly. If the buffer depth falls below the
predetermined lower buffer threshold, the interface clock frequency is
decreased to cause the buffer to drain less quickly. Both lower and upper
threshold levels are used in conjunction with Cell Delay Variation to provide
hysteresis around threshold levels.
Values: Synchronous, Adaptive
Default: Synchronous
AAL1 Format Specifies AAL1 format
−
Basic, E1Cas, Ds1SfCas, or Ds1EsfCas. This value
must be set in accordance with the table on page 4-40 for proper operation.
Payload Scrambling The WANsuite 6450 scrambles/descrambles cell payload bytes at the physical
layer interface using an x
43
+ 1 polynomial. You may enable/disable the