User Manual - Configuration Guide (Volume 3)

Chapter 1

Versatile Routing Platform

QoS overview

overloaded. When the network is congested, it can also guarantee the low delay high pass of some types of packets.

III. Differentiated Service

Differentiated service is to classify services with the same requirement, and to provide different service quality according to the different classification. It does not need the support of special signaling, but implements the packets classification, traffic shaping, traffic policing and queuing through some features of the IP packet. It can also adopt different working modes to assort with the edge network or the core network. Differentiated Service adopts the following technology as an important application to provide point-to-point QoS guarantee:

zCAR: to police the traffic of one flow, several or all the flows.

zGTS: to shape the traffic of one flow, several or all the flows.

zQueuing technology: such queuing debugging technologies as First-In First-Out Queuing, Priority Queuing, Custom Queuing, Weighted fair queuing, Class Based Weighted Fair Queuing operate congestion management on interfaces.

Differentiated Service implements VRP QoS, its specific performances are as follows:

zPackets classification

At the edge of the network, classify operations with different service quality into different types. In the core network, execute the operation of corresponding service quality level according to the classification.

zCongestion Management

When there is congestion on the interface, provide diversified queuing mechanism to cache and allocate the congested packets.

zCongestion Avoidance

Avoid congestion through predicting the congestion state of the network. Congestion Avoidance can decrease the packet loss rate and improve the efficiency of using network.

zTraffic Policing

Control the traffic of single flow, several flows and all the packets, and make the service quality customized.

zTraffic Shaping

Shape the traffic that does not accord with the predefined traffic features so as to facilitate the bandwidth matching. It also can shape every flow or all the packets on the interface.

zInterface Speed Restriction

Tailor the bandwidth of the physical interface to enrich the managing methods of network bandwidth.

1.3 Functions of QoS

The features of QoS enable the network to provide controllable and predicable services for different network applications and network traffic types. With QoS applied to the network, the followings can be implemented:

zNetwork resource control. Users can control the network resources being used. For example, the user can restrict the bandwidth resource to be consumed for FTP transmission in a specific connection, or provide higher priority for a more important data access.

zProviding trimmed network service. If the user is an ISP, QoS can be used to provide trimmed network service with different priorities for different customers.

1-2

Page 71
Image 71
Huawei v200r001 user manual Functions of QoS, III. Differentiated Service