LTE system interfaces-S6b,S6c,S6d,S9,Gi,Gx,Gy,Gz,Sp,Rx+,Wm interfaces
This page of LTE tutorial covers LTE system interfaces viz. S6b, S6c, S6d, S9, Gi, Gx, Gy, Gz, Sp, Rx+, Wm interfaces etc.
Refer LTE system interfaces➤ which mentions S1, X2-C, X2-U, S8, S10, S11, S12, S13, SBc, RX interfaces and refer LTE EPC network interfaces➤ which mentions S1 MME, S1-U, S3, S4, S5, S6a, Gx, S11, SGi interfaces.
Figure-1 depicts various interfaces between LTE system elements.
|LTE system interface||Description|
|S6b||It lies between PDN Gateway and 3GPP AAA Proxy/Server. It deals with mobility related authentication. S6b takes care of transport of commands in order to retrieve and to store mobility parameters. It takes care of transport of static QoS.|
|S6c||This reference point lies between PDN Gateway and 3GPP AAA server. S6c interface is used for mobility related authentications. It takes care of transport of commands to retrieve and to store mobility parameters.|
|S6d||This LTE interface lies between HSS and SGSN (i.e. Serving GPRS Support Node). It is similar to S6a interface.|
|S9||It lies between H-PCRF and V-PCRF in EPS network. H-PCRF is Home Network-PCRF and V-PCRF is Visited network PCRF.|
|Gi||This reference point lies in between packet domain and external packet data network (PDN).
Example, between GGSN and external IP network.
It does transfer of authentication and authorization information during APN (i.e. Access Point Name) provisioning. It takes care of transfer of accounting information during APN provisioning.
|Gx||This reference point lies between PCRF (Policy Charging and Rules Function) and PCEF in EPS network. It enables PCRF to have dynamic control over the PCC behavior at PCEF. Gx interface enables signaling of PCC decisions, negotiation of IP-CAN bearer establishment mode and termination of Gx session .|
|Gy||It is online charging reference point. Gy lies between PCEF (Policy Control Enforcement Function) and OCS (Online Charging Function). It's functionalies are similar to R0.|
|Gz||It is offline charging reference point. Gz lies in between PCEF and CGF. It's functionalies are similar to Rf in EPS.|
|Sp||It lies between SPR and PCRF. SPR stands for subscription profile registry. It takes care of transfer of subscriber information related to IP-CAN based on subscriber Id. It takes care of unsolicited notifications about subscriber information change.|
|Rx+||As we know Rx lies between AF and PCRF. Rx+ is Rx reference point used for EPC. Rx+ interface lies in between PCRF and IP services or proxies to the network. It takes care of transport of application level session information similar to Rx interface.|
|Wm||It lies between PDG and a 3GPP AAA Proxy/Server. It is called intra-operator reference point.|