Figure 11 Ts Processing - Zte ZXR10 5900 Product Description

3.19.2.5 Traffic shaping
Traffic shaping is typically used to restrict traffic and burst for a connection of a network,
so that these packets can be forwarded at a smoother rate. Traffic shaping is usually
implemented by buffer and token bucket. When packets are being sent too fast, they are
first cached into the buffer, before they can be sent at a constant speed under the control
of token bucket.
Traffic Shaping (TS) can shape irregular traffics or those who do not conform to pre-set
traffic characteristics in order to facilitate bandwidth match between upstream and
downstream of the network.
Similar to traffic policing, TS also controls the traffic with token bucket technology. The
difference between TS and traffic policing are as follows: traffic policing drops non-
conforming packets against the traffic characteristics during packet traffic control, while
TS buffers these packets in order to minimize drops and to meet the traffic
characteristics for the packets.
The basic processing of TS is shown in Figure 11, in which the queue for packet
buffering is called a TS queue.

Figure 11 TS processing

The TS can shape packet traffic specified on an interface or for all packets. Arriving
packets are classified first, and those requiring no TS processing will be forwarded
directly, without token bucket processing. Packets in need of TS processing will be
compared against the tokens in the bucket, and the bucket continues to place tokens
into the bucket at the speed specified by user. When there are enough tokens in the
bucket to send packets, the packets are allowed to be forwarded. At the same time,
tokens in the bucket are reduced accordingly based on the packet length. When tokens
in the bucket are reduced so few that no packet can be sent; the packets will be buffered
into the TS queue. If there are packets in the TS queue, the TS will take them from the
queue and send them by a cycle. Each time it sends packets, the packets will be
compared with tokens in the bucket, until the number of tokens in the bucket is reduced
to so few that no packet in the queue can be sent, or until all the packets in the bucket
have been sent.
3.19.2.6 Physical Interface Total Rate Limiting(Link Rate-Limiting, LR)
LR can restrict the total rate of interface packets (including control packets) rate on a
physical interface, and still uses the token bucket for traffic control. If the user has
configured LR which specifies traffic characteristics at an interface of the switch, all
packets sent through the interface will first be processed by port-based token bucket. If
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