Terminology » WiMAX » WiMAX Network Interfaces: R1, R2, R3, R4, R5, R6, R7, R8 Reference Points

WiMAX Network Interfaces: R1, R2, R3, R4, R5, R6, R7, R8 Reference Points

wimax network interface reference point asn csn

This page covers WiMAX network interfaces, also referred to as reference points.

The interface types discussed include R1, R2, R3, R4, R5, R6, R7, and R8. As shown in the figure below, a WiMAX network consists of four basic entities:

  • MS (Mobile Subscriber in mobile WiMAX) or SS (Subscriber Station in fixed WiMAX)
  • NAP (Network Access Provider)
  • NSP (Network Service Provider)
  • Internet

The NAP is responsible for providing radio access functionalities. The NSP is responsible for providing IP connectivity. The Internet provides internet content to the SS/MS interfaced with the NSP.

wimax network interface types or reference points

WiMAX reference points, or interface types, are links that connect two functional entities. They are essentially protocols for these entities to communicate, similar to IP network interface types. This facilitates successful interoperability between equipment from multiple vendors.

The following table describes the WiMAX network interface types:

WiMAX interface typePosition/Functionif any interface
R1Exists between the wireless Subscriber Station (SS) and the Base Station (BS).
R2Exists between the MS (Mobile Station) and the CSN (Connectivity Service Network) in a mobile WiMAX system. EAP traffic flowing from MS to AAA server goes through R2/R3 interface.
R3Exists between the ASN (Access Service Network) and the CSN. RADIUS traffic flowing between the AAA server and the ASN-GW goes through R3.
R4This WiMAX interface exists between one ASN and another WiMAX ASN.
R5Exists between one CSN and another CSN.
R6Is located within the ASN. It represents the link between the ASN-GW and the BS.
R7Is located within the ASN-GW entity. It handles all internal communications within the gateway itself.
R8This WiMAX interface is located within an ASN and represents a link between two BSs.