ADTRAN SHDSL E1 OPERATION Test Capabilities, Inband Loopback Detection, Customer Port, Bert

5. OPERATION

Test Capabilities

The SHDSL T1/E1 NTU has the following test capabil- ities:

•Self diagnostics

•Local loopbacks

•EOC initiated remote loopbacks

•Inband remote loopback detection (E1 mode only)

•Internal bit error rate tester (BERT)

Self Diagnostics

The SHDSL T1/E1 NTU performs self diagnostic tests of its Read Only Memory (ROM), Random Access Memory (RAM), LEDs, and non-volatile configuration setting upon power-up.

Local and Remote Loopbacks

For troubleshooting purposes, the SHDSL T1/E1 NTU provides three types of loopback tests.

1.Dual sided

2.Network

3.Customer

Inband Loopback Detection

Inband remote loopback response is supported on the E1 port. The SHDSL T1/E1 NTU supports V.54 and PN127 inband signalling protocols.

BERT

The SHDSL T1/E1 NTU contains a built-in Bit Error Rate Test (BERT). The BERT involves injecting and detecting a Pseudorandom Binary Sequence (PRBS) toward the network on the selected payload (i.e. G.703 or entire SHDSL payload). The PRBS used in the SHDSL T1/E1 NTU is PRS15 as defined in ITU-T 0.150 and 0.151. It is also known as 2e15 – 1 pattern.

Customer Port

The SHDSL T1/E1 NTU operates in either E1 mode or T1 mode.

E1 Mode

In E1 mode the port features are as follows:

•Carries information at the rate of 2.048 Mbps

•Uses CCS framed format with or without CRC-4

•Operates in either Alternate Mark Inversion (AMI) or High-Density Bipolar 3 (HDB3) line code

•Provides programmable timeslot idle pattern

•Supports ISDN-PRA V3 service

•Displays additional status information via a local VT100 management screen

See Table 5 for E1 port statistics definitions.

T1 Mode

In T1 mode the port features are as follows:

•Carries information at the rate of 1.544 Mbps

•Uses Superframe Format (SF) or Extended Super- frame Format (ESF)

•Operates in either Alternate Mark Inversion (AMI) or Bipolar w/8-Zero Substitution (B8ZS) line code

•Provides programmable timeslot idle pattern

•Monitors the Facility Data Link (FDL) for loopback commands

•Displays additional status information via a local VT100 management screen

See Table 6 for T1 port statistics definitions.

61225236L1-5A Issue 1, August 2003 5