Loopbacks | Allied Telesis 86241-06 guide

24	Patch Release Note

The three C-bits in M-subframe 4 are designated as FEBE bits. The FEBE bits are returned to the far end to indicate the occurrence of a framing error or CP- bit parity error. If none occur, the FEBE bits are set to all ones. One or all of the FEBE bits are set to zero if a CP-bit parity error or an error in the F or M bits is found.

The three C-bits in M-subframe 5 are assigned as a 28.2kbits/s terminal-to- terminal-path maintenance data link. This data link can be switched off at the command interface, If it is switched off, the C-bits in M-subframe 5 are set to all ones. If switched on, the maintenance channel can convey the following information:

■Path Identification Signal.

A set of ASCII text strings that can be used to uniquely identify this particular DS3 path. This can be useful if the DS3 signal is, at some point in its path, multiplexed into a higher order signal such as DS4 or OC-3. It is common for lower-order signals to be switched within a cross-connect. If this happens it is possible that the wrong DS3 signal is switched through to the switch. When this happens the overhead bits are all correct, so there is no indication that the wrong signal has been applied. The Path Identification Signal can be agreed by the two parties at either end of the network and tested to ensure that it is the right DS3 signal that has been received.

■Idle Signal.

A set of ASCII text strings that can be used to provide the location of the source of an idle signal.

■Test Signal.

A set of ASCII text strings that can be used to provide the location of the source of a test signal.

These signals are sent once every second. All other C-bits are for future use.

Loopbacks

The DS3 interface provides four types of loopback; line, payload, diagnostic, and remote. These loopbacks are activated by the ENABLE DS3 TEST command.

Line loopback is shown in Figure 2 on page 24. In this loopback mode the receive signal is looped straight to the transmit signal.

Figure 2: Line Loopback.

Far End

TX

RX

RX

TX

DS3 NSM

DS32

Payload loopback is similar to line loopback. The difference is that only the payload load is looped back from receive to transmit. The overhead is sourced from the DS3 NSM.

Patch 86241-05 for Software Release 2.4.1 C613-10340-00 REV E

Image 24

Allied Telesis 86241-06 manual Loopbacks

Contents

Patch For Rapier Switches PCR Module IPG Level PCR Module SWIPCR Module PIM Level PCR Module BGP Level PCR Module SSH Level PCR 03064 Module Snmp LevelPCR Module SWI Level PCR Module Utility Level PCR 03100 Module Dhcp Level PCR Module FR, PPP LevelPCR 03108 Module Mlds Level PCR 03113 Module Dvmrp Level PCR 03123 Module Dhcp Level PCR Module DS3 LevelPCR Module IPV6 Level PCR Module Ospf Level PCR 02315 Module Snmp Network affecting No PCR Module DS3 Network affecting NoPCR Module IPv6, SWI, IPG, Vlan Network affecting No PCR Module IPG, SWI, Vlan Network affecting No PCR Module Install Network affecting No PCR Module User Network affecting NoPCR Module Utility Network affecting No PCR Module Firewall Network affecting No PCR Module IPG Network affecting No PCR Module Network affecting NoPCR Module Ospf IPG Network affecting No PCR Module Ping Network affecting No PCR 02523 Module QOS, Utility Network affecting No PCR Module TELNET, PING, IPV6, Network affecting NoPCR 02529 Module FIREWALLNetwork affecting No PCR 02532 Module FIREWALLNetwork affecting No PCR 02538 Module Dvmrp Network affecting No PCR Module Classifier Network affecting NoPCR Module IPV6 Network affecting No PCR Module SWI Network affecting No PCR 02574 Module DVMRPNetwork affecting No PCR 02579 Module FIREWALLNetwork affecting NoPCR 02587 Module OSPFNetwork affecting No PCR 02467 Module Core Network affecting No PCR 02469 Module TMNetwork affecting No PCR Module IPG, PIM, SWI Network affecting NoPCR 02495 Module Vlan Network affecting No PCR 02498 Module Vlan Network affecting No PCR 02502 Module Ping, IPv6Network affecting No PCR 02509 Module DVMRPNetwork affecting NoPCR Module DNS Relay Network affecting No PCR Module Vrrp Network affecting No PCR Module BGP Network affecting No PCR Module Tpad Network affecting NoPCR 02277 Module Dvmrp Network affecting No PCR Module TELNET, TTY Network affecting No PCR 02303 Module INSTALLNetwork affecting No PCR 02292 Module IPSECNetwork affecting NoPCR 02294 Module IKMPNetwork affecting No PCR 02301 Module IPGNetwork affecting No PCR Module FR Network affecting No PCR Module IPG/FIREWALL Network affecting NoPCR Module IPG, ETH Network affecting No PCR Module Ipsec Network affecting No PCR Module PPP Network affecting No PCR Module BGP, IPG Network affecting NoPCR 02348 Module Enco Network affecting No PCR Module SCC, SYN, PPP Network affecting No PCR Module FFS, FILE, TTY Network affecting No PCR Module VRRP, TRG Network affecting NoPCR 02397 Module Dvmrp Network affecting No PCR Module Trace Network affecting No PCR Module SNMP, CORE, SHOW, Network affecting NoPCR Module STP Network affecting No PCR Module IPG Network affecting No Module Vrrp PCR 02450 Module IPV6Network affecting No PCR 02452 Module IPv6Network affecting NoPCR 02457 Module IPV6Network affecting No PCR 02463 Module DVMRP, IPG Network affecting No PCR Module Switch Network affecting No DS3 Interfaces PCR Module DHCP, IPG Network affecting No Bit Parity Mode Loopbacks DS3 Configuration Patch Release Note Disable DS3 Debug Disable DS3 Test Enable DS3 Debug Create Framerelay Show Framerelay Dynamic Port Security Availability