ATM OAM F4 and F5 cells

ACX Series routers provide Asynchronous Transfer Mode (ATM) support for the following Operations, Administration, and Maintenance (OAM) fault management cell types:

• F4 alarm indication signal (AIS) (end-to-end)
• F4 remote defect indication (RDI) (end-to-end)
• F4 loopback (end-to-end)
• F5 AIS
• F5 RDI
• F5 loopback

ATM OAM is supported on ACX1000, ACX2000, and ACX2100 routers, and on 16-port Channelized E1/T1 Circuit Emulation MICs on ACX4000 routers.

Junos OS supports the following methods of processing OAM cells that traverse through pseudo wires with circuit cross-connect (CCC) encapsulation:

• Virtual path (VP) pseudo wires (CCC encapsulation)
• Port pseudo wires (CCC encapsulation)
• Virtual circuit (VC) pseudo wires (CCC encapsulation)

For ATM pseudo wires, the F4 flow cell is used to manage the VP level. On ACX Series routers with ATM pseudo wires (CCC encapsulation), you can configure OAM F4 cell flows to identify and report virtual path connection (VPC) defects and failures. Junos OS supports three types of OAM F4 cells in end-to-end F4 flows:

• Virtual path AIS
• Virtual path RDI
• Virtual path loopback

For OAM F4 and F5 cells, IP termination is not supported. Also, Junos OS does not support segment F4 flows, VPC continuity check, or VP performance management functions.