Configuring Channelized STM1 Interfaces
To specify the channel number, include it after the colon (:) in the interface name. For example, a Channelized STM1-to-E1 PIC in FPC 1 and slot 1 will have the following physical interface, depending on the media type:
The E1 channel number can be from 0 through 62.
This section contains the following topics:
Configuring Channelized STM1 Interface Properties
To configure the interface properties for Channelized STM1-to-E1 PICs, include the e1-options and sonet-options statements for both sides of the connection. The following configurations list all the valid statements.
To specify options for each of the E1 channels on the Channelized STM1-to-E1 PIC, include the e1-options statement at the [edit interfaces interface-name] hierarchy level:
- [edit interfaces interface-name]
- e1-options {
- bert-error-rate;
- bert-period;
- fcs (16 | 32);
- (g704 | g704-no-crc4
| unframed);
- idle-cycle-flag (flags | ones);
- (local | remote);
- start-end-flag (filler
| shared);
- timeslots time-slot-number;
- }
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Note: When a channelized STM1 interface experiences a line transition, the E1 channels configured in unframed mode log a large number of drops (around 24,000) as the channelized STM1 interface clocks resynchronize. This does not occur on framed channels, because the framing resynchronizes clocks very quickly. |
To specify options for the SONET/SDH side of the connection, include the sonet-options statement at the [edit interfaces interface-name] hierarchy level:
- [edit interfaces interface-name]
- sonet-options {
-
- aps {
- milliseconds;
- authentication-key key;
- force;
- milliseconds;
- lockout;
- neighbor address;
- paired-group group-name;
- protect-circuit group-name;
- request;
- revert-time seconds;
- switching-mode (bidirectional
| unidirectional);
- working-circuit group-name;
- }
-
- bytes {
- e1-quiet value;
- f1 value;
- f2 value;
- s1 value;
- z3 value;
- z4 value;
- }
- (local | remote);
- }
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Note: On channelized STM1 interfaces, you should configure the clock source on one side of the connection to be internal (the default JUNOS configuration) and on the other side of the connection to be external. |
For information about Frame Relay DLCI limitations for channelized interfaces, see . For more information about Frame Relay DLCIs, see Configuring Frame Relay DLCIs. For information about DLCI sparse mode, see the JUNOS System Basics Configuration Guide.
For more information about specific statements, see , , and . For a configuration example, see .
Configuring Virtual Tributary Mapping of Channelized STM1 Interfaces
You can configure virtual tributary mapping to use KLM mode or ITU-T mode. To configure virtual tributary mapping, include the vtmapping statement at the [edit chassis fpc slot-number pic pic-number] hierarchy level:
By default, virtual tributary mapping uses KLM mode. For more information, see the JUNOS System Basics Configuration Guide.
For the Channelized STM1 IQ and IQE PICs, you can configure virtual tributary mapping by including the vtmapping statement at the [edit interfaces cau4-fpc/pic/port sonet-options] hierarchy level:
- [edit interfaces cau4-fpc/pic/port sonet-options]
- vtmapping (klm
| itu-t);
Table 1 lists the KLM mappings used by the channelized STM1-to-E1 PIC interfaces. The PIC defaults to KLM numbering with an offset of –1; for example, KLM 1= STM1 PIC 0.
Table 1: Channelized STM1-to-E1 Channel Mapping

