Cisco ASR 5000 Series, Обзор продукта

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ASN Paging Controller and Location Registry Overview
▀ Introduction
▄ Cisco ASR 5000 Series Product Overview
OL-22938-02
attempts to reach an idle mode subscriber device, the anchor paging controller alerts the paging group members when it
receives downlink traffic by requesting the paging agent in the base station to signal the idle mode subscriber.
Description of PC/LR Support
The PC/LR runs as a stand-alone function in a separate chassis or as an integrated service on same chassis as the Anchor
Authenticator (A-PC)/Anchor Datapath (A-DP) ASN Gateway. The idle mode LR database uses distributed software
architecture and provides an LR manager task that partitions smaller database volumes across separately running session
manager tasks in the system. The implementation is based on a topologically unaware paging scheme in which the A-PC
does not have global awareness of all member base stations in a paging group. The A-PC uses a single-step paging
operation where paging notifications are sent to the last-reported serving paging controller or directly attached base
station.
Idle mode operation is very important in order for any cellular system to keep the mobile device reachable when it is
inactive. It enables mobility in addition to conserving battery life. Idle mode paging also eliminates the requirements of
independent VLRs/HLRs, when it is supported as an integrated function in the ASN Gateway system.
Licenses
The ASN PC/LR service is a separate product from the ASN Gateway. You must purchase the WiMAX Paging
Controller/Location Register product license separately to enable this service.
Paging and Location Update Procedures
This section provides an overview of the ASN Gateway‘s paging and location update procedures.
The system provides following components for the paging controller, paging group and location registry functionality.
Paging Controller (PC)
The paging controller is a functional entity that administers the activity of idle mode mobile stations in the network. It is
identified by PC ID, which maps to the address of a functional entity in a WiMAX network. In this implementation, the
PC is co-located with ASN Gateway. There are two types of PCs:
Anchor PC : For each idle mode MS, there is a single anchor PC that contains the updated location information
of the MS.
Relay PC : There are one or more other PCs in the network, called relay PCs, that participate in relaying paging
and location management messages between the paging agent and the anchor PC.