3Com 10014299 manual Physical Interface Line, Rate, Shape all the flows on Ethernet interface

	Physical Interface Line Rate 677
	Shape all the flows on Ethernet interface 1.
	[Router] interface ethernet1
	[Router-Ethernet1] qos gts any cir 45000000 cbs 5800000 ebs 5800000
Physical Interface Line	By using the physical interface line rate (LR), the total rate for sending packets
Rate	(including the emergency packet) on a physical interface can be limited.
	LR also uses the token bucket to perform the traffic control. If LR is configured in
	an interface of the router, the LR token bucket first processes all the packets sent
	by this interface. If the token bucket has sufficient tokens, the packet can be sent;
	otherwise, the packet enters the QoS queue for congestion management. Thus,
	the packet traffic through this physical interface can be controlled.
	Figure 216 Schematic diagram of LR processing

Tokens enter bucket at the given speed

incoming packets

outgoing packets

classify

queue

Token Bucket

buffer

As the token bucket is used to control the traffic, when there is any token in the token bucket, the burst transmission of the packet is allowed. When there is no token in the token bucket, the packet cannot be sent until a new token is generated in the token bucket. Thus, there is a limitation that packet traffic cannot be larger than the generating speed of the token, therefore, it realizes that the traffic is limited and burst traffic is allowed to pass through at the same time.

Compared with CAR, LR can limit all the packets passing through the physical interface. CAR is implemented in the IP layer and is ineffective on the packets that are not processed by the IP layer. It is simple to use LR when the user only requires the limitation of all packets.

LR Configuration To configure the physical interface line rate, perform the following configurations in the interface view.

Table 717 Configure the Physical Interface LIne Rate

Operation	Command
Configure the physical interface	qos lr cir committed-rate[ cbs
bandwidth	burst-size [ ebs excess-burst-size ]
	]
Delete the configured physical interface	undo qos lr
bandwidth

By default, the line rate is not performed on the physical interface.