R3303-HP HSR6800 Routers Layer 2 - WAN Configuration Guide

5
InARP
On an ATM PVC connection, you can use the Inverse Address Resolution Protocol (InARP) to obtain the
IP address of the remote end connected to the PVC. In this way, you do not need to manually configure
the IP address of the remote end. Figure 4 sh
ows how InARP works.
Figure 4 Inverse address resolution procedure of InARP
ATM OAM
OAM in the ITU-T I.610 recommendation (02/99) and Operation Administration and Maintenance in
LUCENT APC User Manual (03/99).
Whichever expansion is adopted, OAM provides a way of detecting faults, isolating faults, and
monitoring network performance without interrupting ongoing services. By inserting OAM cells, which
are constructed in the standard ATM cell format, in cell streams, you can obtain specific information
about the network.
OAM F5 loopback
The OAM F5 loopback function of ATM operates in the following workflow on a PVC:
Each side of the PVC sends OAM cells to its peer periodically. On receiving an OAM cell from the sender,
the receiver returns the OAM cell to the sender. If the sender receives the cell within the specified period
(which is the interval frequency of sending OAM cells), the PVC is normal. If the sender fails to receive
an OAM cell sent by itself, the PVC might be faulty. Then the sender continues to send OAM cells for
detection (the sending interval is retry-frequency). If the sender still does not receive an OAM cell, the
PVC is actually faulty.
Two approaches are available for implementing the OAM F5 Loopback function: manual (OAMPing)
and auto (OAM Frequency). In the OAMPing approach, send OAM cells manually; this approach is
usually used for diagnosis. In the OAM Frequency approach, you must configure an ATM interface to
send OAM cells regularly at a certain interval; this approach is usually used for automatic link status
checking.
OAM continuity check
When enabled, the OAM Continuity Check (CC) function periodically sends OAM cells to check
whether a connection is idle or has failed.