Where should QoS marking be performed?
Once classification has occurred, traffic should be marked, to indicate the required level of QoS service for that traffic. Marking can occur within either the Layer-2 header or the Layer-3 header. The point on the network where traffic is classified and marked is known as the trust boundary.
What is QoS classification and marking?
QoS classification tools categorize packets by examining the contents of the frame, cell, and packet headers, whereas marking tools allow the QoS tool to change the packet headers for easier classification. These different types or classes of traffic are typically called service classes in QoS terminology.
What is 802.1 p Dscp QoS?
When the QoS mode on a port is set to be trusted, the received 802.1P/DSCP. DSCP is a 6-bit packet header value used for traffic classification and priority assignment. is considered trustworthy and the frame is allowed to exit with those values intact.
Is Dscp a Layer 3?
Layer 3 DSCP marking: Enables the switch to set, change, and honor prioritization policies by using the Differentiated Services (Diffserv) bits in the ToS byte of IPv4 headers and Traffic Class byte of IPv6 headers.
How is network traffic classification used in QoS?
When used in conjunction with network traffic classification, marking network traffic is the foundation for enabling many quality of service (QoS) features on your network. This module contains conceptual information and the configuration tasks for marking network traffic.
How does the QoS packet marking feature work?
The QoS Packet Marking feature allows you to mark packets by setting the IP precedence bit or the IP differentiated services code point (DSCP) in the Type of Service (ToS) byte, and to associate a local QoS group value with a packet.
How does Cisco Express Forwarding Mark network traffic?
In order to mark network traffic, Cisco Express Forwarding must be configured on both the interface receiving the traffic and the interface sending the traffic. Traffic marking can be configured on an interface, a subinterface, or an ATM permanent virtual circuit (PVC). Marking network traffic is not supported on the following interfaces:
What does Multiprotocol Label Switching ( MPLS ) do?
Multiprotocol Label Switching (MPLS) experimental (EXP) field on all imposed label entries Traffic marking allows you to fine-tune the attributes for traffic on your network. This increased granularity helps single out traffic that requires special handling and, thus, helps to achieve optimal application performance.