3Com 10014299 manual Frame Relay Traffic Shaping, Undo Fr traffic-shaping

258 CHAPTER 17: CONFIGURING FRAME RELAY

Remove the association between a Frame Relay	undo	fr-classclass-name
class and a Frame Relay interface or PVC
Enable the Frame Relay traffic shaping	fr traffic-shaping
Disable the Frame Relay traffic shaping	undo	fr traffic-shaping

Configure Frame Relay Quality of Service (QoS) is a set of technologies adopted to meet the users'

QoSrequirements in throughput, delay jitter, delay and packet loss ratio. Briefly speaking, QoS technologies provides network services of different qualities for different requirements.

On a Frame Relay interface, the user can use the general QoS to provide the services, such as traffic policing, traffic shaping, congestion management, and congestion avoidance. For details, please refer to the relative description in the part of QoS.

Furthermore, a Frame Relay network has its own QoS mechanisms, including Frame Relay traffic shaping, Frame Relay traffic policing, Frame Relay congestion management, Frame Relay discard eligibility (DE) rule list and Frame Relay queueing management. According to different requirements, the network service provider can provide various services, such as bandwidth restriction and bandwidth reservation.

Compared with the general QoS, Frame Relay QoS can provide the service of QoS for each PVC on an interface. However, the general QoS can only provide the service of QoS on the whole interface. Therefore, the Frame Relay QoS can provide more flexible quality services for users.

Figure 81 Frame Relay QoS application

Data flow direction

Traffic Shaping	Traffic Policing
DTE	NNI	Frame Relay
DCE		Network
Router A	Router B
DE Rule	Congestion
	Management

Frame Relay Traffic Shaping

The Frame Relay traffic shaping can control the normal traffic size and the burst traffic size transmitted from a PVC and enable the Frame Relay PVC to transmit these packets at a relatively average rate.

In a Frame Relay network, the bottleneck will often occur at the boundary of segments if the bandwidths of different segments do not match. As shown in Figure 82, Router B transmits packets to Router A at the rate of 128 kbps whereas the maximum interface rate of Router A is only 64 kbps. In this case, the bottleneck will occur at the place where Router A is connected to the Frame Relay network, and thereby resulting in the congestion that prevents the data from normal transmitting.