Nokia 7705 - 3.5 Network Ingress; 3.5.1 Network Ingress Classification

QoS and QoS Policies
104
Quality of Service Guide
3HE 11014 AAAC TQZZA Edition: 01
3.5 Network Ingress
This section contains the following topics for traffic flow in the network ingress
direction:
• Network Ingress Classification
• Network Ingress Queuing
• Network Ingress Scheduling
• Network Ingress Shaping to Fabric
• Configurable Network Ingress Shaping to Fabric
• Network Fabric Shaping on the Fixed Platforms
3.5.1 Network Ingress Classification
Network ingress traffic originates from a network egress port located on another
interworking device, such as a 7710 or 7750 Service Router or another 7705 SAR,
and flows from the network toward the fabric in the 7705 SAR.
The ingress MPLS packets can be mapped to forwarding classes based on EXP bits
that are part of the headers in the MPLS packets. These EXP bits are used across
the network to ensure an end-to-end network-wide QoS offering. With pseudowire
services, there are two labels, one for the MPLS tunnel and one for the pseudowire.
Mapping is performed using the EXP values from the outer tunnel MPLS label. This
ensures that the EXP bit settings, which may have been altered along the path by the
tandem label switch routers (LSRs), are used to identify the forwarding class of the
encapsulated traffic.
Ingress GRE and IP packets are mapped to forwarding classes based on DSCP bit
settings of the IP header. GRE tunnels are not supported for IPv6; therefore, DSCP
bit classification of GRE packets is only supported for IPv4. DSCP bit classification
of IP packets is supported for both IPv4 and IPv6.
Untrusted traffic uses multi-field classification (MFC), where the traffic is classified
based on any IP criteria currently supported by the 7705 SAR filter policies; for
example, source and destination IP address, source and destination port, whether or
not the packet is fragmented, ICMP code, and TCP state. For information on MFC,
refer to the 7705 SAR Router Configuration Guide, “Multi-field Classification (MFC)”
and “IP, MAC, and VLAN Filter Entry Commands”.