Cisco ASR 5000 Series, Обзор продукта

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ASN Gateway Overview
▀ ASN Gateway in a WiMAX Network
▄ Cisco ASR 5000 Series Product Overview
OL-22938-02
The CSN also provides location-based services, connectivity for peer-to-peer services, provisioning, authorization
and/or connectivity to IP multimedia services, and support for lawful intercept services in the WiMAX radio access
network.
Important:
CSN is out of the scope of this document.
WiMAX Reference Points and Interfaces
A reference point (RP) in a WiMAX network is a conceptual link. An RP connects two groups of functions that reside
in different functional entities of an ASN, CSN, or mobile station (MS). It is not necessarily a physical interface; an RP
becomes a physical interface only when the functional entities on either side of it are contained in different physical
devices.
Following are the reference points implemented with the ASN Gateway for WiMAX mobility functions:
R3 Reference Point— Consists of the set of control plane protocols between the ASN and the CSN to support
AAA, policy enforcement, and mobility management capabilities. It also encompasses the bearer plane
methods (for example, tunneling) to transfer user data between the ASN and the CSN. R3 supports three types
of clients: PMIPv4, CMIPv4, CMIPv6 (this is IPv4 and IPv6 support for Proxy Mobile IP (PMIP)) and Client
Mobile IP (CMIP).
R4 Reference Point— Consists of the set of control and bearer plane protocols originating and terminating in
various functional entities of an ASN that coordinate MS mobility between ASNs and ASN Gateways. R4 is
the only interoperable RP between similar or heterogeneous ASNs.
R5 Reference Point—C onsists of the set of control plane and bearer plane protocols for internetworking
between the CSN operated by the home NSP and that operated by a visited NSP.
R6 Reference Point—C onsists of the set of control and bearer plane protocols for communication between the
base station and the ASN Gateway. The bearer plane is an intra-ASN datapath between the base station and
ASN gateway. The control plane includes protocols for datapath establishment, modification, and release
control, in accordance with the MS mobility events. R6, in combination with R4, may serve as a conduit for
exchange of MAC state information between base stations that cannot interoperate over R8.
R7 Reference Point—C onsists of an optional set of control plane protocols, for example, AAA and policy
coordination in the ASN gateway as well as other protocols for coordination between the two groups of
functions identified in R6. The decomposition of the ASN functions using the R7 protocols is optional.
Important:
To provide high throughput and high density call processing, the ASN Gateway integrates both the
Decision Point and Enforcement Point functions. Therefore, the R7 reference point is not exposed.