Техническая Инструкция для Cisco Cisco ASR 5000
Contents
Introduction
EPS Bearer QoS Profile
Basic QoS Feature Support
APN-AMBR enforcement support
Default-Bearer QOS enforcement support
SDF (PCC-rule) Level enforcement support
DSCP marking support
Bearer Binding Support
Related Cisco Support Community Discussions
Introduction
This article gives a brief Overview on Quality of Service (QoS) support in Cisco Aggregated
Service Router (ASR) 5x00 Packet Gateway (PGW). QOS enforcement support is one of the
important capability that PGW needs to support in Evolved Packet Core (EPC) network. There are
multiple aspects of QoS that needs to be supported in a PGW in order to spec compliant. An
Evolved Packet System (EPS) bearer is the level of granularity for bearer level QoS control in the
EPC and other Access types.
Service Router (ASR) 5x00 Packet Gateway (PGW). QOS enforcement support is one of the
important capability that PGW needs to support in Evolved Packet Core (EPC) network. There are
multiple aspects of QoS that needs to be supported in a PGW in order to spec compliant. An
Evolved Packet System (EPS) bearer is the level of granularity for bearer level QoS control in the
EPC and other Access types.
EPS Bearer QoS Profile
The EPS bearer QoS profile includes the parameters QCI, ARP, GBR and MBR. Each EPS bearer
(GBR and Non-GBR) is associated with the following bearer level QoS parameters:
(GBR and Non-GBR) is associated with the following bearer level QoS parameters:
QoS Class Identifier (QCI): A QCI is a scalar that is used as a reference to access node-specific
parameters that control bearer level packet forwarding treatment (e.g. scheduling weights,
admission thresholds, queue management thresholds, link layer protocol configuration, etc.), and
that have been pre-configured by the operator owning the access node (e.g. eNodeB). A one-to-
one mapping of standardized QCI values to standardized characteristics is captured Technical
Specification (TS) 23.203.
parameters that control bearer level packet forwarding treatment (e.g. scheduling weights,
admission thresholds, queue management thresholds, link layer protocol configuration, etc.), and
that have been pre-configured by the operator owning the access node (e.g. eNodeB). A one-to-
one mapping of standardized QCI values to standardized characteristics is captured Technical
Specification (TS) 23.203.
Allocation and Retention Priority (ARP): The ARP shall contain information about the priority
level (scalar), the pre-emption capability (flag) and the pre-emption vulnerability (flag). The primary
purpose of ARP is to decide whether a bearer establishment / modification request can be
accepted or needs to be rejected due to resource limitations (typically available radio capacity for
GBR bearers). ARP is also used at Policy and Charging Enforcement Function (PCEF)/ Policy and
Charging Rule Function (PCRF) for Bearer-Binding along with QCI. Bearer-Binding is a process of
binding the Policy and Charging control (PCC)-rules to a particular EPS bearer.
level (scalar), the pre-emption capability (flag) and the pre-emption vulnerability (flag). The primary
purpose of ARP is to decide whether a bearer establishment / modification request can be
accepted or needs to be rejected due to resource limitations (typically available radio capacity for
GBR bearers). ARP is also used at Policy and Charging Enforcement Function (PCEF)/ Policy and
Charging Rule Function (PCRF) for Bearer-Binding along with QCI. Bearer-Binding is a process of
binding the Policy and Charging control (PCC)-rules to a particular EPS bearer.
Guaranteed Bit Rate (GBR): Applicable to only GBR bearers. GBR denotes the bit rate that can
be expected to be provided by a GBR bearer. It is expected that the Radio Access Network (RAN)
and core would reserve the GBR for the bearer.
be expected to be provided by a GBR bearer. It is expected that the Radio Access Network (RAN)
and core would reserve the GBR for the bearer.
Maximum Bit Rate (MBR): Applicable to both GBR and Non-GBR bearers. The MBR limits the bit
rate that can be expected to be provided by a bearer (e.g. excess traffic may get discarded by a
rate shaping function). The MBR of a particular GBR bearer may be set larger than the GBR.
rate that can be expected to be provided by a bearer (e.g. excess traffic may get discarded by a
rate shaping function). The MBR of a particular GBR bearer may be set larger than the GBR.