No relevant resource is found in the selected language.

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Read our privacy policy>Search

Reminder

To have a better experience, please upgrade your IE browser.

upgrade

NE20E-S2 V800R010C10SPC500 Feature Description - Network Reliability 01

This is NE20E-S2 V800R010C10SPC500 Feature Description - Network Reliability
Rate and give feedback:
Huawei uses machine translation combined with human proofreading to translate this document to different languages in order to help you better understand the content of this document. Note: Even the most advanced machine translation cannot match the quality of professional translators. Huawei shall not bear any responsibility for translation accuracy and it is recommended that you refer to the English document (a link for which has been provided).
Basic Concepts

Basic Concepts

OAMPDUs

EFM works at the data link layer and uses protocol packets called OAM protocol data units (OAMPDUs). EFM devices periodically exchange OAMPDUs to report link status, helping network administrators effectively manage networks. Figure 6-2 shows the format and common types of OAMPDUs. Table 6-2 lists and describes fields in an OAMPDU.

Figure 6-2 OAMPDU format
Table 6-2 Fields and descriptions in an OAMPDU
Field Description

Dest addr

Destination MAC address, which is a slow-protocol multicast address 0x0180-C200-0002. Network bridges cannot forward slow-protocol packets. EFM OAMPDUs cannot be forwarded over multiple devices, even if OAM is supported or enabled on the devices.

Source addr

Source address, which is a unicast MAC address of a port on the transmit end. If no port MAC address is specified on the transmit end, the bridge MAC address of the transmit end is used.

Type

Slow protocol type, which has a fixed value of 0x8809.

Subtype

Subtype of a slow protocol. The value is 0x03, which means that the slow sub-protocol is EFM.

Flags

Status of an EFM entity:
  • Remote Stable

  • Remote Evaluating

  • Local Stable

  • Local Evaluating

  • Critical Event

  • Link Fault

Code

OAMPDU type:
  • 0X00: Information OAMPDU

  • 0X01: Event Notification OAMPDU

  • 0X04: Loopback Control OAMPDU

Table 6-3 describes common types of OAMPDUs.

Table 6-3 OAMPDU types

OAMPDU Type

Description

Information OAMPDU

errored symbol period event

Event Notification OAMPDU

Used to monitor links. If an errored frame event, errored symbol period event, or errored frame second summary event occurs on an interface, the interface sends an Event Notification OAMPDU to notify the remote interface of the event.

Loopback Control OAMPDU

Used to enable or disable the remote loopback function.

Connection Modes

EFM supports two connection modes: active and passive. Table 6-4 describes capabilities of processing OAMPDUs in the two modes.

Table 6-4 Capabilities of processing OAMPDUs in active and passive modes

Capability

Active Mode

Passive Mode

Initiate a connection request by sending an Information OAMPDU during the discovery process.

Supported

Not supported

Respond to a connection request during the discovery process.

Supported

Supported

Send Information OAMPDUs.

Supported

Supported

Send Event Notification OAMPDUs.

Supported

Supported

Send Loopback Control OAMPDUs.

Supported

Not supported

Respond to Loopback Control OAMPDUs.

Supported (The remote EFM entity must work in active mode.)

Supported

NOTE:
  • An EFM connection can be initiated only by an OAM entity working in active mode. An OAM entity working in passive mode waits to receive a connection request from its peer entity. Two OAM entities that both work in passive mode cannot establish an EFM connection between them.

  • An OAM entity that is to initiate a loopback request must work in active mode.

Translation
Download
Updated: 2019-01-02

Document ID: EDOC1100055473

Views: 12283

Downloads: 4

Average rating:
This Document Applies to these Products
Related Version
Related Documents
Share
Previous Next