Overview of QoS policies on 7210 SAS-Sx/S 1/10GE and 7210 SAS-Sx 10/100GE

QoS policies are applied on service ingress, access port egress, network port ingress and egress, and network IP interfaces ingress when configured 7210 SAS-Sx/S 1/10GE and 7210 SAS-Sx 10/100GE operates with MPLS uplinks.

These policies allow users to configure the following:

classification rules for how traffic is mapped to FCs
FC association with meters and meter parameters used for policing (rate-limiting)
queuing parameters for shaping
QoS marking/interpretation

There are several types of QoS policies:

service ingress policies for access SAP ingress

Service ingress QoS policies are applied to the customer-facing SAPs. Traffic that enters through the SAP is classified to map it to an FC. FCs are associated with meters/policers on ingress. The mapping of traffic to meters can be based on combinations of customer QoS marking (IEEE 802.1p bits), IP criteria, and MAC criteria.
access egress policies for access port egress

Access egress policies are analogous to SAP egress policies as defined in the 7750 SR series of products. The difference is the point of attachment. An access egress policy is applied on the physical port as opposed to the logical port (SAP) for SAP egress policy. It applies to all SAPs on a port. An access egress QoS policy maps the traffic egressing on customer facing ports into various queues and marks the traffic accordingly.
access ingress policies for access port ingress

An access ingress policy is applied to the physical port instead of the SAP; the policy applies to all SAPs configured on the specific access port. At ingress, the access ingress QoS policy uses dot1p, DEI with dot1p, or IP DSCP values to assign an FC and profile to traffic, which facilitates the classification of traffic received on the access port. The FC is associated with meters at ingress. An access ingress QoS policy allows the user to define up to one meter per FC for unicast traffic, and up to one meter per FC for multipoint traffic (that is, broadcast, multicast, and unknown-unicast) for multipoint services. The system supports up to 16 meters per access ingress QoS policy.

Note:
This policy is available only when the node is operating in sap-scale mode high. See the 7210 SAS-Mxp, S, Sx, T Services Guide and 7210 SAS-Mxp, R6, R12, S, Sx, T Basic System Configuration Guide for more information about the sap-scale-mode command.
network policies for network and hybrid port, ingress and egress

The 7210 SAS-Sx/S 1/10GE and 7210 SAS-Sx 10/100GE support two types of network QoS policies, one applied to a network IP interface and the other to a network port or a hybrid port. Network QoS policies are applied to IP interfaces. On ingress, the policy applied to an IP interface maps incoming MPLS LSP EXP values to FC and profile state for the traffic received from the core network. On egress, the policy maps FC and profile state to MPLS LSP EXP values for traffic to be transmitted into the core network. The network policy applied to a network port maps incoming IP packets, DSCP, or dot1p values, to the FC and the profile state for the traffic received from the core network. On egress, the policy maps FC and profile state to DSCP or dot1p values for IP traffic to be transmitted into the core network.
network queue policies for network and hybrid port, egress

Network queue policies are applied on egress to network or hybrid ports when operating in network mode. The policies define the FC queue characteristics for these entities. The FCs are mapped to the queues. There are 16 queues at the port level. FC-to-queue mapping is static and not configurable. The number of queues is not user-configurable, and the software allocates 16 queues at the port level.
port scheduler policies for access port, network port, and hybrid port egress

Port scheduler policies are applied on egress for access, network, and hybrid ports. These policies allow the user to define queue scheduling attributes, such as strict-priority queuing and weighted queuing.
slope policies

Slope policies are applied to the egress queues on the access, network, and hybrid ports. These policies define the WRED congestion management attributes, such as drop probability and thresholds for high-profile and low-profile traffic.
remark policies for access port, network port, and hybrid port egress marking

Remark policies are applied to access ports/SAPs, network ports/IP interfaces, and hybrid ports/SAPs/IP interfaces to configure the marking values for different forwarding classes and profiles.These policies enable marking of packet header QoS fields for packets that are forwarded out of the port, SAP, or IP interface. See Remark policies for more information.

The characteristics of the FC meters, including the number of FC meters for unicast traffic and the meter characteristics (like CIR, PIR, and so on) are defined within the policy. Each FC can be associated with different unicast parameters. A service ingress QoS policy also defines up to three (3) meters per FC to be used for multipoint traffic for multipoint services. Up to 32 meters, in total, are supported per Service ingress QoS policies.

In the case of the VPLS, the following types of forwarding are supported (which is not to be confused with FCs): unicast, multicast, broadcast, and unknown. Multicast, broadcast, and unknown types are flooded to all destinations within the service, while the unicast forwarding type is handled point-to-point in the service.

The FCs are mapped to 16 queues at the port level (8 for unicast and 8 for multicast). FC-to-queue mapping is static and not configurable. The number of queues is not user configurable and the software allocates 16 queues at the port level. An access egress policy also defines the remarking of the FC-to-packet header bits (for example, IEEE 802.1p bits in the Layer 2 VLAN header, and others.).

The following applies to the use of QoS policies on hybrid ports:

Network queue policies are supported for queue configuration of egress queues on hybrid ports. These egress queues are shared by traffic sent out of SAPs and network IP interfaces configured on hybrid ports.
Network QoS policies of type ‟ip-interface” are supported for network IP interfaces on hybrid ports. The behavior is similar to the existing behavior for network IP interfaces on network ports. It supports per IP interface ingress classification and policing and egress marking (only EXP marking for MPLS traffic).
Network QoS (type = port) policies are supported for hybrid ports. The behavior is similar to existing behavior for network ports. It supports per port ingress classification and policing and egress marking (dot1p and/or DSCP marking) for IP control packets.
SAP ingress QoS policies are supported for SAPs configured on hybrid ports. The behavior is similar to existing behavior for access SAP ingress. It supports per SAP ingress classification and policing.
For marking traffic sent out of SAPs and IP traffic sent out of IP interfaces configured on hybrid ports, users must use the network QoS policy of type ‟port”, with an option to mark dot1p, DSCP, or both.

Note:
If DSCP remarking or both is specified, the DSCP field is not marked for the traffic sent out of the Layer 2 SAPs.

Service ingress, access egress, and network QoS policies are defined with a scope of either template or exclusive. Template policies can be applied to multiple entities (such as SAPs and ports); exclusive policies can be applied to only a single entity. One service ingress QoS policy can be applied to a specific SAP.

An access ingress policy is applied to the physical port instead of the SAP; the policy applies to all SAPs configured on the specific access port. At ingress, the access ingress QoS policy uses dot1p, DEI with dot1p, or IP DSCP values to assign a forwarding class and profile to traffic, which facilitates the classification of traffic received on the access port. The FC is associated with meters at ingress. An access ingress QoS policy allows the user to define up to one meter per forwarding class for unicast traffic, and up to one meter per forwarding class for multipoint traffic (that is, broadcast, multicast, and unknown-unicast) for multipoint services. The system supports up to 16 meters per access ingress QoS policy.

An access egress policy can be applied to an access port. One access egress QoS policy can be applied to the access port. One network QoS policy can be applied to a specific IP interface, network port, or hybrid port based on the type of network QoS policy. A network QoS policy defines both ingress and egress behavior. One network queue policy can be applied to the network port or hybrid port. If no QoS policy is applied to a SAP, port, or interface, a default QoS policy is applied.

The 7210 SAS-Sx/S 1/10GE and 7210 SAS-Sx 10/100GE can operate in either the low SAP scale mode or high SAP scale mode. In low SAP scale mode, SAP and service scaling is limited by the amount of CAM resources available for the SAP ingress policy (both classification and meters). In the high SAP scale mode, SAP and service scaling are significantly higher compared to the low SAP scale mode and use access port ingress policies. The use of network port policies remains unchanged when the system is operating in high SAP scale mode; however, the high SAP scale mode assumes that the user requires Layer 2 uplinks, and uses access port ingress and egress policies on those uplinks.

SAPs configured on ports operating in hybrid mode cannot be configured to use access ingress QoS policies. Therefore, the access-ingress-qos port-mode option is not supported for ports configured in hybrid mode.

The following QoS policies are supported on access ports and SAPs in the low SAP scale mode:

service ingress policy for SAP ingress classification and metering using the following:
- CAM-based classification and metering
- table-based classification and CAM-based metering
service egress policy for SAP egress queuing, shaping, and scheduling with an egress policy for marking only
access egress policy for access port egress queuing, shaping, scheduling, and marking (this policy is mutually exclusive with the use of service egress policies)

The following QoS policies are supported on access ports and SAPs in the high SAP scale mode:

the choice of an access port ingress policy on access service delivery ports or per-SAP ingress policies; Nokia recommends using an access port ingress policy for higher SAP scaling
access egress policy for port egress queuing, shaping, scheduling, and marking (this policy is mutually exclusive with the use of service egress policies)

The following table describes the major functions performed by QoS policies.

Table: QoS policy types and descriptions for 7210 SAS-Sx/S 1/10GE and 7210 SAS-Sx 10/100GE devices in network mode
Policy type	Applied at…	Description	Section
Service ingress	SAP ingress	defines up to 16 FC meters and meter parameters for traffic classification defines match criteria to map flows to the meters, based on any one of the criteria	Service ingress QoS policies
Access egress	Access port	defines up to 8 FC queues and queue parameters for traffic classification maps FCs to the queues defines FC to remarking values defines CIR levels and PIR weights that determine how the queue is prioritized by the scheduler	Access egress QoS policies on 7210 SAS-T, 7210 SAS-Sx/S 1/10GE, and 7210 SAS-Sx 10/100GE
Access Ingress	Access Port	defines dot1p and IP DSCP classification criteria to use defines up to 16 meters per access ingress QoS policy	Access ingress QoS policies
Network (of type ‟ip-interface”)	IP interface	used for classification/marking of MPLS packets at ingress, defines MPLS LSP-EXP to FC mapping and 12 meters used by FCs at egress, defines FC to MPLS LSP-EXP marking	Network QoS policies in network mode
Network (of type ‟port”)	Network and hybrid ports	used for classification/marking of IP packets at ingress, defines DSCP or dot1p to FC mapping and 8 meters at egress, defines FC to DSCP, dot1p marking, or both	Network QoS policies in network mode
Network queue	Network ports and hybrid ports	defines FC mappings to network queues and queue characteristics for the queues	Network queue policies in network mode
Slope	Access ports, network ports, and hybrid ports	enables or disables the high-slope, low-slope, and non-TCP parameters within the egress pool	Slope policy parameters
Port scheduler	Access ports, network ports, and hybrid ports	defines the parameters for the port scheduler	Port scheduler policies for 7210 SAS-T
Remark	Network port, access ports, and hybrid ports	applied at egress, defines the FC-to-priority bits (DSCP or dot1p or EXP) marking	Remark policies on 7210 SAS-Mxp, 7210 SAS-R6, 7210 SAS-R12, 7210 SAS-S 1/10GE, 7210 SAS-Sx 10/100GE, and 7210 SAS-T (network mode)