User's Manual

CHAPTER 1. Overview of Mobile WiMAX System

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The ACR supports the Convergence Sublayer (CS) and performs the packet classification

and Packet Header Suppression (PHS) functions. When the ACR carries out the header

compression function, it supports Robust Header Compression (ROHC) defined in the

NWG standard.

In addition, the ACR performs the paging controller and location register functions for an

MS in Idle Mode.

In authentication, the ACR performs the authenticator function and carries out the key

distributor function to manage the higher security key by interworking with the AAA server

as an AAA client. At this time, RAS performs the key receiver function to receive the

security key from the key distributor and manage it.

The ACR interworks with the AAA server of CSN for authentication and charging services

and with the HA of CSN for Mobile IP (MIP) service. The ACR as FA of MIP supports

Proxy MIP (PMIP).

The RAS performs the Service Flow Management (SFM) function to create/change/release

connections for each Service Flow (SF) and the admission control function while

creating/changing connections. In regard to the SFM function of the RAS, the ACR carries

out the SF Authentication (SFA) and SFID management functions. The ACR carries out the

SFA function to obtain the QoS information from Policy Function (PF) and apply it in the

SF creation and performs the SFID management function to create/change/release SFID

and map SF according to the packet classification.

In handover, the RAS performs the handover control function to determine the execution of

the handover and deal with corresponding handover signaling. The ACR confirms the

neighbor RAS list and relays the handover signaling message to the target system.

At this time, the ACR and the RAS carries out the context function to exchange the context

information between the target system and the serving system.

The RAS provides Admission Control to collect/manage the MS’s radio resource

information and the RAS’s own radio resource information (e.g., BSID). When load

balancing is required based on Admission Control results, it performs resource

management through FA overriding and BS init HO (Handover).

ASN System Function

For the detailed description about the system functions, refer to the system

description for each system provided by Samsung.