Fault Detection Technologies for IP Networks
Fault detection technologies are classified as special detection technologies or common detection technologies by usage scope.
- Special fault detection technologies include:
ETH OAM, which apply to the data link layer
Common fault detection technologies include Bidirectional Forwarding Detection (BFD), which applies to all layers.
Each layer of the TCP/IP reference model has fault detection mechanisms:
Data link layer: ETH OAM, Spanning Tree Protocol (STP), Rapid Spanning Tree Protocol (RSTP), MSTP
Network layer: Hello mechanism provided by protocols, Virtual Router Redundancy Protocol (VRRP), and graceful restart (GR)
Application layer: heartbeat and retransmission mechanisms provided by protocols
Fault detection modes include:
Asynchronous mode: Probe packets are sent periodically.
Echo mode: Received packets are sent back to a peer without any change.
