Cisco ASR 5000 Series, Обзор продукта

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Glossary
▀ Environmental Information
▄ Cisco ASR 5000 Series Product Overview
OL-22938-02
PDP Session . unique association of a subscriber with a network access service given by the combination of MSISDN,
APN and IP address. A PDP session can consist of one or more PDP contexts (one primary and zero or more
secondary).
PDSN. Packet Data Serving Node. The PDSN is a part of the 3G network that performs packet processing and re-
direction to the mobile user's home network through communications with the Home Agent (HA).
PEP. Performance Enhancing Proxy. PEP is used to improve the performance of the Internet protocols (e.g., TCP) on
network paths where native performance suffers due to characteristics of a link or sub-network on the path.
Pi Interface. The packet data interface from the Foreign Agent to Internet or Home Agent.
Plain NAS message . a NAS message with a header including neither a message authentication code nor a sequence
number.
PLMN. Public Land Mobile Network. A term used to designate a GSM, GPRS or UMTS public mobile
communications network
Point Code (PC). A unique address for a node in an SS7 environment.
Policy Decision. The set of policy information AGW receives from E-PDF in a Gx/Ty Diameter message. E-PDF
constructs policy decision on the basis of Application Function events and events received over Gx/Ty interface .
Policy Information. The set of policy related data stored in E-PDF associated to a user, including information
determined via real-time analysis of an SDP offer/answer exchange derived information in the context of an IMS
session, information derived from a pre configured charging rule and preconcerted rule set. These information includes
at least charging rules, media component data, binding information and authorized QoS. Policy information such as
charging rules and authorized QoS are sent in a policy decision by the E-PDF to the AGW for enforcement.
Pool-area . A pool area is an area within which a MS may roam without need to change the serving CN node. A pool
area is served by one or more CN nodes in parallel. All the cells controlled by a RNC or BSC belong to the same one (or
more) pool area(s).
Port. A defined physical or logical connection where data enters or leaves a network device.
POS. Packet over SONET.
Preconcerted Charging Rule. Charging rule created and configured in E-PDF by the operator.
PPP. Point-to-Point Protocol. A protocol defined by RFC-1661 that allows for IP connectivity between network
devices.
Primary PDP Context. The first PDP context activated by a UE. At the primary PDP context activation an IP address
(the PDP address) is assigned to a UE. When activated a primary PDP context is general purpose (i.e. with no associated
TFT filters), during its lifetime may change to dedicated (i.e. with associated TFT filters).
PTI . Procedure Transaction Identity. An identity which is dynamically allocated by the UE for the UE requested ESM
procedures. The procedure transaction identity is released when the procedure is completed.
PSC. Packet Services Card. The PSC is an application card providing memory and processing capabilities for handling
subscriber sessions.
Pull Model. A communication model where a policy decision is requested by the AGW.
Push Model. A communication model where a policy decision is sent unsolicited by the authorizing entity (i.e. E-PDF)
to the AGW.
Q
QoS. Quality of Service. A measure of the service quality provided to a subscriber. In the IP environment, this relates to
acceptable levels of quality including bandwidth guarantees, latency, packet ordering, and other service-related levels of
service.
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