How The Atm Interface Handles Loopback Cells Received; Automatic Disabling Of F5 Oam Services; Table 6: Handling Of F4 And F5 Loopback Cells Received - Juniper JUNOSE 11.1.X - LINK LAYER CONFIGURATION 4-7-2010 Configuration Manual

JUNOSe 11.1.x Link Layer Configuration Guide

How the ATM Interface Handles Loopback Cells Received

The ATM interface responds to received F4 and F5 loopback cells as indicated in
Table 6 on page 20.

Table 6: Handling of F4 and F5 Loopback Cells Received

Automatic Disabling of F5 OAM Services

The router automatically disables all F5 OAM fault management and VC integrity
services configured on a VC when you change the administrative status of the
corresponding ATM interface, ATM AAL5 interface, or ATM 1483 subinterface from
enabled to disabled.
To set the administrative status of an interface to disabled, use the atm shutdown
command (for an ATM interface), the atm aal5 shutdown command (for an ATM
AAL5 interface), or the atm atm1483 shutdown command (for an ATM 1483
subinterface). You can also use the shutdown command to disable the interface.
When F5 OAM is disabled, the OAM VC status field in the show atm vc atm command
display indicates that the VC is not managed. The VC does not receive or transmit
F5 OAM cells while F5 OAM is disabled. For examples of the show atm vc atm
command display, see "show atm vc atm" on page 94.
When the corresponding ATM interface, ATM AAL5 interface, or ATM 1483
subinterface is reenabled, the router automatically restores F5 OAM services on the
associated VCs.
20
Operations, Administration, and Management of ATM Interfaces
Loopback Cell Received
F4 and F5 end-to-end loopback cells and
segment loopback cells with the loopback
location field set to all 1s (ones) and the
loopback indication set.
F4 and F5 segment loopback cells with the
loopback location field set to all 0s (zeros) and
the loopback indication set.
F4 and F5 end-to-end loopback cells and
segment loopback cells with the loopback
location field set to the loopback location ID of
the ATM interface and the loopback indication
set.
F5 end-to-end loopback cells with the loopback
location field set to a value other than all 1s and
the loopback location ID of the ATM interface.
F5 segment loopback cells with the loopback
location field set to other than all 1s (ones), set
to all 0s (zeros), or set to the loopback location
ID of the ATM interface.
ATM Interface Response
Clears the loopback indication (sets it to all
zeros) and loops back the received cell.
Resets the loopback indication and the
location ID to all 1s (ones) and loops back the
received cells.
Clears the loopback indication and loops back
the received cell without resetting the location
ID.
Discards the cell.
Discards the cell.