Chapter 19
| Quality of Service Commands
– 452 –
new-dscp
- Differentiated Service Code Point (DSCP) value. (Range: 0-63)
Default Setting
None
Command Mode
Policy Map Class Configuration
Command Usage
◆
You can configure up to 16 policers (i.e., class maps) for ingress ports.
◆
The
committed-rate
and
peak-rate
cannot exceed the configured interface
speed, and the
committed-burst
and
peak-burst
cannot exceed 16 Mbytes.
◆
The trTCM as defined in RFC 2698 meters a traffic stream and processes its
packets based on two rates – Committed Information Rate (CIR) and Peak
Information Rate (PIR), and their associated burst sizes - Committed Burst Size
(BC) and Peak Burst Size (BP).
◆
The PHB label is composed of five bits, three bits for per-hop behavior, and two
bits for the color scheme used to control queue congestion. A packet is marked
red if it exceeds the PIR. Otherwise it is marked either yellow or green
depending on whether it exceeds or doesn't exceed the CIR.
The trTCM is useful for ingress policing of a service, where a peak rate needs to
be enforced separately from a committed rate.
◆
The meter operates in one of two modes. In the color-blind mode, the meter
assumes that the packet stream is uncolored. In color-aware mode the meter
assumes that some preceding entity has pre-colored the incoming packet
stream so that each packet is either green, yellow, or red. The marker (re)colors
an IP packet according to the results of the meter. The color is coded in the DS
field [RFC 2474] of the packet.
◆
The behavior of the meter is specified in terms of its mode and two token
buckets, P and C, which are based on the rates PIR and CIR, respectively. The
maximum size of the token bucket P is BP and the maximum size of the token
bucket C is BC.
◆
The token buckets P and C are initially (at time 0) full, that is, the token count
Tp(0) = BP and the token count Tc(0) = BC. Thereafter, the token count Tp is
incremented by one PIR times per second up to BP and the token count Tc is
incremented by one CIR times per second up to BC.
When a packet of size B bytes arrives at time t, the following happens if trTCM is
configured to operate in color-blind mode:
■
If Tp(t)-B < 0, the packet is red, else
■
if Tc(t)-B < 0, the packet is yellow and Tp is decremented by B, else
■
the packet is green and both Tp and Tc are decremented by B.
Summary of Contents for EX-3524
Page 2: ......
Page 28: ...Figures 28 ...
Page 34: ...Section I Getting Started 34 ...
Page 58: ...Chapter 1 Initial Switch Configuration Setting the System Clock 58 ...
Page 72: ...Chapter 2 Using the Command Line Interface CLI Command Groups 72 ...
Page 156: ...Chapter 5 SNMP Commands Notification Log Commands 156 ...
Page 164: ...Chapter 6 Remote Monitoring Commands 164 ...
Page 218: ...Chapter 7 Authentication Commands Management IP Filter 218 ...
Page 268: ...Chapter 8 General Security Measures Port based Traffic Segmentation 268 ...
Page 292: ...Chapter 9 Access Control Lists ACL Information 292 ...
Page 312: ...Chapter 10 Interface Commands Power Savings 312 ...
Page 324: ...Chapter 11 Link Aggregation Commands Trunk Status Display Commands 324 ...
Page 366: ...Chapter 15 Address Table Commands 366 ...
Page 428: ...Chapter 17 VLAN Commands Configuring Voice VLANs 428 ...
Page 572: ...Chapter 25 IP Interface Commands IPv6 Interface 572 ...
Page 578: ...Section I Appendices 578 ...