LTE: What are interfaces present in LTE architecture ?

Question

Can somebody please explain the procedure of Detach Request if it is triggered by Network.?

Answer 1

Vimal Mentioned most of the interfaces so i am just adding an image showing all interfaces ....

Comments

Thanks Sachi, do we have the protocol definition also for each interface in the similar manner.

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This image  i taken from internet ...
About the short description i have not prepared full...

But u can refer http://lteworld.org/ltefaq/what-are-lte-interfaces for description

Answer 2

As you have included so many tags in your query. There are a number of interfaces are present in LTE architecture.

One entity talks to other entity through an interface. I would like to point out some of major interfaces.

1. Uu interface exists between UE and eNodeB.
2. S1-u interface exists between eNodeB and SGW.
3. S1-C interface exists between eNodeB and MME.
4. S11 interface exists between MME and SGW.
5. S5/S8 interface exists between SGW and PGW.
6. Gx interface exists between PGW/PCEF and PCRF.
7. SGi interface exists between external world ip network and PGW.
8. S6a interface lies between MME and HSS.

Comments

Vimal i have one doubt ...most of the figure it is not mentioned ...

what is the interface between S-GW and S-GW ??

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Sachidananda , I never found any interface between two SGWs.

Answer 3

The following are LTE Interfaces : (Ref: TS 23.401 v 841)

S1-MME :- Reference point for the control plane protocol between E-UTRAN and MME.
S1-U:- Reference point between E-UTRAN and Serving GW for the per bearer user plane tunnelling and inter eNodeB path switching during handover.
S3:- It enables user and bearer information exchange for inter 3GPP access network mobility in idle and/or active state.
S4:- It provides related control and mobility support between GPRS Core and the 3GPP Anchor function of Serving GW. In addition, if Direct Tunnel is not established, it provides the user plane tunnelling.
S5:- It provides user plane tunnelling and tunnel management between Serving GW and PDN GW. It is used for Serving GW relocation due to UE mobility and if the Serving GW needs to connect to a non-collocated PDN GW for the required PDN connectivity.
S6a:- It enables transfer of subscription and authentication data for authenticating/authorizing user access to the evolved system (AAA interface) between MME and HSS.
Gx:- It provides transfer of (QoS) policy and charging rules from PCRF to Policy and Charging Enforcement Function (PCEF) in the PDN GW.
S8:- Inter-PLMN reference point providing user and control plane between the Serving GW in the VPLMN and the PDN GW in the HPLMN. S8 is the inter PLMN variant of S5.
S9:- It provides transfer of (QoS) policy and charging control information between the Home PCRF and the Visited PCRF in order to support local breakout function.
S10:- Reference point between MMEs for MME relocation and MME to MME information transfer.
S11:- Reference point between MME and Serving GW.
S12:- Reference point between UTRAN and Serving GW for user plane tunnelling when Direct Tunnel is established. It is based on the Iu-u/Gn-u reference point using the GTP-U protocol as defined between SGSN and UTRAN or respectively between SGSN and GGSN. Usage of S12 is an operator configuration option.
S13:- It enables UE identity check procedure between MME and EIR.
SGi:- It is the reference point between the PDN GW and the packet data network. Packet data network may be an operator external public or private packet data network or an intra operator packet data network, e.g. for provision of IMS services. This reference point corresponds to Gi for 3GPP accesses.
Rx:- The Rx reference point resides between the AF and the PCRF in the TS 23.203.
SBc:- Reference point between CBC and MME for warning message delivery and control functions.