Communication equipment Fundamental-reliability

Reliability metrics, very simple, how long is the average bad time, how long the average can be repaired

Reliability metrics include: MTTR, MTBF, and availability.

Typically use MTTR(Mean time to Repair) and mean time between failures MTBF(Mean timebetween Failure) These two indicators evaluate the reliability of a product or system.

IP network Reliability technology and IP network fault detection technology

· dedicated fault detection technologies include:

§  Automatic Protection Switching (transport Layer) is intended to be used for transport networks.

§  Eth-oam (link layer), including EFM, CFM, y.1731.

§  MPLS (multiprotocol Label Switching) OAM (MPLS)

· General Fault detection techniques include: BFD is a balm, where all can be used, it is easy and other things linkage.

The TCP/IP network Reference Model is classified as a hierarchy, and there are fault detection mechanisms at each level:

· Transport Layer/Physical layer:APS(Automatic Protection switching)

· link layer:MPLS OAM, Eth-oam,stp/rstp/mstp/rrpp

· Network layer: Hello mechanism for each protocol, VRRP (Virtual Router redundancyprotocol), GR (Graceful Restart)

· Application layer: The heartbeat and retransmission mechanism of various application layer protocols

Mode of network fault detection:

· asynchronous mode: Send probe messages Periodically, hey, are you still alive?

· query mode: Send a series of message request confirmation, do a physical examination to prove that you are alive.

· echo mode: Send the message to the end without making any changes reflect back, you say you, I echo whatever just.

IP network Protection Switching technology

Data Communication network protection switching standard is 50ms. Link Redundancy is the basis for protection switching.

Link protection methods include:

· End-to-end protection: 1:1, 1:n, up, very good distinction, one equals 2, meaning two work, one equals 1, meaning is a work.

· Local protection: FRR (Fast ReRoute), fast switching to backup routing.

This article is from the "Digital Kid" blog, please make sure to keep this source http://dcboy.blog.51cto.com/8059630/1829022

Communication equipment Fundamental-reliability