Configuring Fractional E1 Time Slots
By default, all the time slots on an E1 interface are used. To configure the number of time slots allocated to a fractional E1 interface, include the timeslots statement at the [edit interfaces interface-name e1-options] hierarchy level:
There are 32 time slots on an E1 interface. Time slot 0 is always reserved for framing and cannot be used to configure a fractional E1 interface.
Time slot numbering constraints vary for different E1 PICs, as follows:
- For 4-port E1 PICs, the configurable time slot range is 1 through 31 (time slot 0 is reserved for framing).
- For 10-port Channelized E1 and 10-port Channelized E1 Intelligent Queuing (IQ) PICs, the configurable time slot range is 2 through 32 (time slots 0 and 1 are reserved for framing).
- For Enhanced Intelligent Queuing (IQE) PICs, the configurable time slot range is 2 through 32.
- NxDS0 time slots configured on either a channelized STM1 IQ interface or a channelized E1IQ interface are numbered from 1 to 31 (0 is reserved), while fractional E1 time slots are numbered from 2 to 32 (0 and 1 are reserved).
- For fractional E1 interfaces only, if you connect a 4-port E1 PIC to a device that uses time slot numbering from 2 through 32, you must subtract 1 from the configured number of time slots. To do this, include the timeslots statement at the [edit interfaces interface-name e1-options] hierarchy level, and offset 1 from the specified slot number.
 | Note: When configuring fractional E1 time slots, you also must include the framing g704 statement at the [edit interfaces e1-fpc/pic/port e1-options] hierarchy level. |
To configure ranges, use hyphens. To configure discontinuous time slots, use commas. Do not include spaces.
Example: Configuring Fractional E1 Time Slots
In this example, time slots are offset by 1 to compensate for the fractional E1 interface being connected to a device that uses time slot numbering from 0 through 31.
Use Time Slots 4 Through 6, 11, and 25
Use Time Slots 1 Through 10
Use Time Slots 1 Through 5, 10, and 24
