H3C Technologies H3C S12500 Series Switches - Manual (Page 19)

8
Configuring Ethernet OAM
Ethernet OAM overview
Background
With features such as ease of use and low price, Ethernet has gradually become the major underlying
technology for today's local area networks (LANs). Recently, with the emergence of Gigabit Ethernet and
10-Gigabit Ethernet, Ethernet is gaining popularity in metropolitan area networks (MANs) and wide
area networks (WANs) as well.
In the beginning, Ethernet is mainly used in LANs, which have low reliability and stability requirements.
This is why an effective management and maintenance mechanism for Ethernet has been absent all
along, hindering the usage of Ethernet in MANs and WANs. Implementing Operation, Administration
and Maintenance (OAM) on Ethernet networks has now become an urgent matter.
Ethernet OAM is a tool that monitors Layer 2 link status and addresses common link-related issues on the
"last mile." You can monitor the status of the point-to-point link between two directly connected devices
by enabling Ethernet OAM on them.
Major functions of Ethernet OAM
Ethernet OAM can effectively promote your management and maintenance capabilities over Ethernet
networks, guaranteeing the stability of the networks. Ethernet OAM provides the following functions:
• Link performance monitoring—Monitors the performance indices of a link, including packet loss,
delay, and jitter, and collects traffic statistics of various types.
• Fault detection and alarm—Checks the connectivity of a link by sending OAM protocol data units
(OAMPDUs) and reports to the network administrators when a link error occurs.
• Remote loopback—Checks link quality and locates link errors by looping back OAMPDUs.
Ethernet OAMPDUs
Ethernet OAM works on the data link layer. Ethernet OAM reports the link status by periodically
exchanging OAMPDUs between devices, so that the administrator can effectively manage the network.
Ethernet OAMPDUs include the following types: Information, Event Notification, and Loopback
Control. Figure 1 shows the formats of different types of OAMPDUs.