Mapping between differentiated services code point (DSCP) and local priority

5

IP packets carry the DSCP field to indicate the QoS preference. The mapping between the priority fields must be configured on the gateway to retain packet priorities when the packets traverse different networks. You can run the display qos map-table command to view the mapping between priorities, or run the input command in the priority mapping table view to configure the mapping between priorities.

Other related questions:
How to configure mapping between DSCP priorities and local priorities on S series switches
You can run the following commands to configure mapping between DSCP priorities and local priorities on S series switches (except the S1700): - ip-dscp-inbound dscp-value phb service-class [ green | yellow | red ]: configures mapping between DSCP priorities and local priorities for IP packets on the inbound interface. - ip-dscp-outbound service-class { green | yellow | red } map dscp-value: configures between DSCP priorities and local priorities for IP packets on the outbound interface.

How to query the local signaling point codes on the U1960
Run the [%eSpace U1960(config)]#show interoffice command.

Default mappings between priorities on an AR
Default mappings between priorities on an AR are as follows: For the AR120&AR150&AR160&AR200&AR500 series, AR510 series, AR1200 series, AR2204, AR2220L, and AR2220E, table 1 shows the mappings from 802.1p priorities to DSCP priorities, and the mappings between 802.1p priorities remain unchanged. Table 3 lists the mappings from DSCP priorities to 802.1p priorities, and the mappings between DSCP priorities remain unchanged. The mappings between MPLS EXP priorities remain unchanged. For AR2201-48FE, AR2202-48FE, AR2220, AR2240, and AR3200&AR3600 series, table 2 lists the mappings from 802.1p priorities to DSCP priorities and local priorities, and the mappings between 802.1p priorities remain unchanged. Table 4 lists the mappings from DSCP priorities to 802.1p priorities and local priorities, and the mappings between DSCP priorities remain unchanged. Table 5 lists the mappings from MPLS EXP priorities to local priorities, and the mappings between MPLS EXP priorities remain unchanged.

Priority mapping
Packets transmitted over different networks carry different QoS precedence fields, for example, EXP field on an MPLS network, 802.1p field on a virtual local area network (VLAN), and DSCP field on an IP network. The mapping between priority fields must be configured on the gateway to retain priorities of packets when the packets traverse different networks. The priority mapping mechanism provides the mapping from precedence fields of packets to internal priorities (local precedences) or the mapping from internal priorities to precedence fields of packets. This mechanism uses the DiffServ domain to manage and record the mapping of precedence fields and internal priorities. When packets reach the AR, the AR maps priorities in packets or the default 802.1p priorities of inbound interfaces to local priorities. The AR then determines the queues that packets enter based on the mapping between internal priorities and queues and performs traffic shaping, congestion avoidance, and queue scheduling. In addition, the AR can re-mark priorities in outgoing packets so that the downstream device can provide different QoS levels based on packet priorities.

If you have more questions, you can seek help from following ways:
To iKnow To Live Chat
Scroll to top