Card
(DS1/E1-56 only) The Card subtab allows you to provision the encapsulation, port usage and retiming, and VT mapping for the DS1/E1-56 card.
 
Item
Description
Transport Mode
Sets the encapsulation mode:
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SONET—(Default for DS1) Transports DS1s in VT1.5s.
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AU4—(Default for E1) Transports DS1s and E1s in a structured VC4 payload (STS-3c).
Note
Switching from one transport mode to another is not allowed if a port is in a circuit, in service, or selected as a timing reference for the NE.
Operating Mode
Sets the port usage:
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All DS1—(Default) All 56 ports are used as DS1 ports. Ports 1 to 28 are with retiming capability. Any of the 56 ports can be selected to provide timing reference to the NE.
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All E1—All 56 ports are used as E1 ports. Ports 1 to 21 are with retiming capability. Any of the 56 ports can be selected to provide timing reference to the NE.
The restrictions on switching between these selections is based on existing circuits, ports being in service, and port usage as an NE reference source.
Retiming Enabled
When checked, retimes the transmit clock to the clock reference of the NE, removing the asynchronous relationship between electrical line and SONET transport time domains for the electrical path. If the Operating Mode is All DS1, Retiming Enabled is checked and cannot be changed.
When not checked for E1 mode, leaves the port as “through-timed,” which means that the transmit clock is extracted from the DS1/E1 data from the SONET payload coming from the backplane.
Port to VT Mapping
Selects the ordering in which ports are mapped into the VT1.5s within an STS-1. This setting applies to a group of ports associated with the same STS-1.
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GR 253 interleaves the ports into the VT1.5 (DS1-14 compatible). In this mapping, sequential port numbers are mapped to interleave the 7 VT groups of VT1.5s. Interleaving by VT group essentially means that the ports follow the order of transmission of the VT1.5s, as indicated in GR-253.
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INDUSTRY (default for E1 mode) maps sequential port numbers to fill each VT group in order. In this mapping, ports in sequential progression are packed into VTs filling an entire VT group before moving on to the next VT Group.
Apply
Applies changes made to the fields in the tab.
Reset
Cancels any changes to the tab and returns the fields to their last-saved settings.
Help
Displays context-sensitive help.
 

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