Levels Of Reliability Requirements; Principles For High-Reliablity Ip Networking - Huawei NetEngine80E Configuration Manual - Reliability

HUAWEI NetEngine80E/40E Router
Configuration Guide - Reliability
Availability
The availability identifies the utility of a system. You can improve the device availability by
increasing the MTBF and decreasing the MTTR.
In the telecommunication industry, 99.999% availability means that service interruption caused
by device failures must be less than 5 minutes each year.
In actual networking, network faults and service interruption are inevitable. Therefore, providing
technologies to enable device to recover from failures rapidly becomes very important. Such
technologies can improve device availability by reducing MTTR.

1.1.3 Levels of Reliability Requirements

The objective and implementation method of the reliability vary with the level of reliability
requirements.
Table 1-1
methods.
Table 1-1 Levels of reliability requirements
Level
1
2
3

1.1.4 Principles for High-Reliablity IP Networking

Technologies for reliable networking cover the hierarchy networking, redundancy technology,
and load balancing technology.
The principles for high-reliablity IP networking are as follows:
l
Issue 02 (2011-09-10)
lists three requirement levels and describes their objectives and implementation
Objective
Less faults in the
software and hardware
of a system
No impact on a system
when a default occurs
Rapid recovery from a
fault that affects the
system
Hierarchical networking: A network is divided into three layers, core layer, convergence
layer, and edge layer. According to the current service status and future service prediction,
redundancy backup is required on a device connected to access nodes on the edge layer.
The active and standby nodes connect to convergence nodes. Devices of convergence layer
are dual-homed to single node multi-device of the upper layer or to multi-node device of
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Implementation Method
l Hardware: simplified design, standardized circuits,
reliable application of components, reliability
control over purchased components, reliable
manufacture, environment adaptability, and
reliability testing (HALT/HASS)
l Software: checklist for the software reliability design
l Redundancy design
l Switchover policy
l High availability of switchover
l Fault detection
l Fault diagnosis
l Fault isolation
l Fault recovery
1 Reliability Overview
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