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3GPP Interfaces description
General map
SAE/LTE map
This document provide clickable maps about 3GPP network nodes and
interfaces. For readability reasons two different maps have been provided:
the first one shows the 2G/3G network configuration (general map), the
second one shows the SAE/LTE configuration with new nodes and
interfaces (SAE/LTE map).
Please read the readme page for a correct use of the document
Useful links
Readme
Mobile Interface - ankitsaxena
Readme
This is a quick reference guide which shows the mobile network architecture
and related 3GPP interfaces together with their brief description. The main
scope of this guide, is to provide a quick and visual overview. If you need
official technical documentation, please look at the useful link section.
It’s not intended to be used as an official technical specification or as
product/solution guideline.
The technical information are taken form other documents that are subject to
modifications, such modifications may not result in an update of this
document.
Not all nodes/interfaces are mentioned in this document but only the most
common and the ones that are more often included in Ericsson business
solutions.
However reference to Ericsson official documentation is provided to allow
further detail collection.
Back to index
Mobile Interface - ankitsaxena
Other PLMN
RBS
RBS
RBS
OSS
SCP SMS-C HLR/HSS GMLC
GGSN SGSN
SGSN
MSC-S CSCF MRFP
BGCF
MGW MGW
RNC RNC BSC
HUB/RXI
MSC
GMSC
VLR
MGCF
VLR
RBS
Mut
Mur
Gom
Gn Gn Gs E Nc
G
Mg Mj
Nb
Mc Mc
Mb
Iur
Iub
A-bis
A A
Gb IuCS
IuPS
Ext. PDN
H
Uu Um
LI-IMS LEMF
X1
X2
Ge
Gf Gd
Gr
C
MSC
D
SSF
E
C
EIR AUC General map
Lh
Gi
Mub
Back to index
Lg
Lc
MSC-S
SCF
SSF-SCF
SCF-HLR
Gc
Gd
Mobile Interface - ankitsaxena
RBS
HLR/HSS
SGSN
RNC
BSC
RBS
Iub Uu
Um
Gr
MME
Serving GW
PCRF
Gb IuPS
S3
S4
S11
eNodeB
S1-U
Non-3GPP access
S2a
S7
SGi
S6a
IP Network
PDN GW
S12
EIR
S13
eNodeB
X2
MME
S10
MSC/VLR
SGs
Sv
S6d
ePDG
Non trusted
S2b
SWn S2c
AAA
S6b
SWa/STa
SAE/LTE map
S1-MME
Back to index
S5/S8
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
A BSC MGW,
MSC
The A interface between the MSC and its BSS is specified in the 48-series of Technical
Specifications.
The BSS-MSC interface is used to carry information concerning:
- BSS management;
- call handling;
- mobility management.
BSSAP
(DTAP+BSSMAP)
Back to general map
A
Control plane
(DTAP / BSSMAP)
BSSAP
SCCP
MTP3
MTP2
MTP1/L1
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
A-bis BSC BTS The Abis interface refers to the interface between the BSC and the BTS. The Abis
interface allows control of the radio equipment and radio frequency allocation in the BTS. RR, BTSM
A-Bis Back to general map
Control plane
BTSM / RR
LAPD
L1
Mobile Interface - ankitsaxena
Interface
(
Between
Description Top Protocols
Node Node
C HLR GMSC
The Gateway MSC server must interrogate the HLR of the required subscriber to obtain
routing information for a call or a short message directed to that subscriber.
Signalling on this interface uses the Mobile Application Part (MAP), which in turn uses the
services of Transaction Capabilities.
MAP
C Back to general map
MTP3-b
SAAL-NNI
AAL5
ATM
MTP1/L1
L1
IP
MTP3
MTP2
M3UA
SCTP
SCCP
MAP
Control plane
TCAP
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
D HLR VLR
This interface is used to exchange the data related to the location of the mobile station
and to the management of the subscriber. The main service provided to the mobile
subscriber is the capability to set up or to receive calls within the whole service area. To
support this, the location registers have to exchange data. The VLR informs the HLR of
the location of a mobile station managed by the latter and provides it (either at location
updating or at call set-up) with the roaming number of that station. The HLR sends to the
VLR all the data needed to support the service to the mobile subscriber. The HLR then
instructs the previous VLR to cancel the location registration of this subscriber.
Exchanges of data may occur when the mobile subscriber requires a particular service,
when he wants to change some data attached to his subscription or when some
parameters of the subscription are modified by administrative means.
MAP
D Back to general map
MTP3-b
SAAL-NNI
AAL5
ATM
MTP1/L1
L1
IP
MTP3
MTP2
M3UA
SCTP
SCCP
MAP
Control plane
TCAP
Mobile Interface - ankitsaxena
Interface
((
Between
Description Top Protocols
Node Node
E MSC MSC
When a mobile station moves from one MSC area to another during a call, a handover
procedure has to be performed in order to continue the communication. For that purpose
the MSC servers have to exchange data to initiate and then to realise the operation.
After the handover operation has been completed, the MSC servers will exchange
information to transfer A-interface or Iu-interface signalling as defined in 3G TS 23.009.
When a short message is to be transferred between a Mobile Station and Short Message
Service Centre (SC), in either direction, this interface is used to transfer the message
between the MSC server serving the Mobile Station and the MSC server, which acts as
the interface to the SC.
MAP
E Back to general map
MTP3-b
SAAL-NNI
AAL5
ATM
MTP1/L1
L1
IP
MTP3
MTP2
M3UA
SCTP
SCCP
MAP
Control plane
TCAP
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
F MSC EIR This interface is used between MSC server and EIR to exchange data, in order that the
EIR can verify the status of the IMEI retrieved from the Mobile Station. MAP
F Back to general map
MTP3-b
SAAL-NNI
AAL5
ATM
MTP1/L1
L1
IP
MTP3
MTP2
M3UA
SCTP
SCCP
MAP
Control plane
TCAP
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
G VLR VLR When a mobile subscriber moves from a VLR area to another Location Registration
procedure will happen. This procedure may include the retrieval of the IMSI and
authentication parameters from the old VLR. MAP
G Back to general map
MTP3-b
SAAL-NNI
AAL5
ATM
MTP1/L1
L1
IP
MTP3
MTP2
M3UA
SCTP
SCCP
MAP
Control plane
TCAP
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
H HLR AUC
When an HLR receives a request for authentication and ciphering data for a Mobile
Subscriber and it does not hold the requested data, the HLR requests the data from the
AuC. The protocol used to transfer the data over this interface is not standardised. In
Ericsson nodes the AUC is integrated into the HLR node.
MAP
H Back to general map
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Gb SGSN BSC
The Gb interface connects the SGSN and the BSS, and allows the exchange of signaling
information between them. It also allows the exchange of signaling information and user
data between the SGSN and Mobile Stations (MSs).
The BSS-SGSN interface is used to carry information concerning:
- packet data transmission;
- mobility management.
GMM, SNDCP
Gb Back to general map
Back to SAE/LTE map
Control plane User plane
GMM SNDCP
Frame Relay
L1
LLC
BSSGP
NS
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Gc GGSN HLR
This optional signalling path may be used by the GGSN to retrieve information about the
location and supported services for the mobile subscriber, to be able to activate a packet
data network address.
There are two alternative ways to implement this signalling path:
- if an SS7 interface is implemented in the GGSN, signalling between the GGSN
and the HLR uses the Mobile Application Part (MAP), which in turn uses the services of
Transaction Capabilities (TCAP)
MAP
Gc Back to general map
MTP3-b
SAAL-NNI
AAL5
ATM
MTP1/L1 L1 IP
MTP3
MTP2
M3UA
SCTP
SCCP
MAP
Control plane
TCAP
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Gd SGSN SMS-
C
This interface is used to transfer short messages between SGSN/IP-SM-GW and SMS-
GMSC or SMS-IWMSC over GPRS. Signalling on this interface uses the Mobile
Application Part (MAP) (see TS 29.002 [26]). MAP
Gd Back to general map
MTP3-b
SAAL-NNI
AAL5
ATM
MTP1/L1 L1
MTP3
MTP2
SCCP
Control plane
MAP
TCAP
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Ge SGSN SCP
The Ge interface connects the SGSN to a Service Control Point (SCP) with Customized
Applications for Mobile Network Enhanced Logic (CAMEL), and grants the SCP real-time
control over subscriber service usage on the SGSN.
The Ge interface enables the SCP to have real-time control over subscriber service
usage on the SGSN. The main application is prepaid charging. Once CAMEL interaction
is activated, the SCP can instruct the SGSN to allow or disallow service invocation, to
insert data in Charging Data Records (CDRs), and to report on service usage.
CAMEL
Ge Back to general map
MTP3-b
SAAL-NNI
AAL5
ATM
MTP1/L1 L1 IP
MTP3
M3UA
MTP2
SCTP
Control plane
CAP/INAP
TCAP
SCCP
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Gf SGSN EIR This interface is used between SGSN and EIR to exchange data, in order that the EIR
can verify the status of the IMEI retrieved from the Mobile Station. MAP
Gf Back to general map
Control plane
CAP
TCAP
SCCP
MTP3
MTP2
E1/T1
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Gn SGSN SGSN,
GGSN
This interface is used to support mobility between the SGSN and GGSN. The Gn
interface is used when GGSN and SGSN are located inside one PLMN. The Gn interface
also includes a part which allows SGSNs to communicate subscriber and user data,
when changing SGSN.
GTP
Gn Back to general map
Control plane User plane
GTP-C GTP-U
AAL5
ATM
L1 Ethernet
UDP
IPSec/GRE
IP
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Gr SGSN HLR
This interface is used to exchange the data related to the location of the mobile station
and to the management of the subscriber. The main service provided to the mobile
subscriber is the capability to transfer packet data within the whole service area. The
SGSN informs the HLR of the location of a mobile station managed by the latter. The
HLR sends to the SGSN all the data needed to support the service to the mobile
subscriber. Exchanges of data may occur when the mobile subscriber requires a
particular service, when he wants to change some data attached to his subscription or
when some parameters of the subscription are modified by administrative means.
MAP
Gr Back to general map
Back to SAE/LTE map
MTP3-b
SAAL-NNI
AAL5
ATM
MTP1/L1 L1
MTP3
MTP2
SCCP
Control plane
MAP
TCAP
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Gs SGSN MSC,
VLR
The SGSN may send location information to the MSC/VLR via the optional Gs interface.
The SGSN may receive paging requests from the MSC/VLR via the Gs interface. The
MSC/VLR may indicate to an SGSN, via the Gs interface, that an MS is engaged in a
service handled by the MSC.
BSSAP+
Gs Back to general map
MTP3-b
SAAL-NNI
AAL5
ATM
MTP1/L1 L1
MTP2
MTP3
Control plane
BSSAP+
SCCP
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Gom OSS SGSN,
GGSN The Gom interface connects the SGSN to Operation & Maintenance (O&M) equipment in
the O&M network, making it possible for an operator to communicate with the SGSN.
O&M protocols
(FTP, SSH, HTTP,
etc)
Gom Back to general map
Mobile Interface - ankitsaxena
Interface
((
Between
Description Top Protocols
Node Node
Mub OSS RNC O&M interface for RBS (between RBS and WCDMA OSS) -
Mur OSS RBS O&M interface for RNC (between RNC and WCDMA OSS) -
Mut OSS RXI O&M interface for HUB-RXI (between HUB-RXI and WCDMA OSS) -
Mub, Mur, Mut Back to general map
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Iub RNC RBS
When the RNS consists of a Radio Network Controller (RNC) and one or more Node B,
this interface is used between the RNC and Node B to support the services offered to the
UMTS users and subscribers.
The interface also allows control of the radio equipment and radio frequency allocation in
the Node B.
The interface is specified in the 25.43x series of Technical Specifications.
NBAP
Iub Back to general map
Back to SAE/LTE map
Control plane User plane Transport Control plane
SAAL-UNI SAAL-UNI
AAL5 AAL2 AAL5
Iu FP
ATM
L1
NBAP
Q.2630.1
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
IuCS MSC RNC
The RNS-MSC interface is used to carry information concerning:
- RNS management;
- Call handling;
- Mobility management.
RANAP
IuCS Back to general map
Control plane User plane Transport Control plane
RANAP
SCCP
MTP3-B MTP3-B
SAAL-NNI AAL-2 SAR SSCS SAAL-NNI
AAL5 AAL2 AAL5
ATM
L1
Iu UP
Q.2630.1
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
IuPS SGSN RNC
The IuPS interface between SGSN and RNS/BSS is used to carry information
concerning:
- Packet data transmission;
- Mobility management.
RANAP, GTP-U
IuPS Back to general map
Back to SAE/LTE map
Control plane User plane
RANAP
SCCP
MTP3-B UDP
SAAL-NNI IP
L1
AAL5
ATM
GTP-U
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Iur RNC RNC
The Iur interface provides capability to support radio interface mobility between RNSs, of
UEs having a connection with
UTRAN. This capability includes the support of handover and radio resource handling
between RNSs.
RNSAP
Iur Back to general map
Control plane User plane Transport Control plane
RNSAP
SCCP
MTP3-B MTP3-B
SAAL-NNI SAAL-NNI
AAL5 AAL2 AAL5
Iu FP
Q.2630.1
ATM
L1
Mobile Interface - ankitsaxena
Interface
((
Between
Description Top Protocols
Node Node
Lc GMLC gsmS
CF This interface is used to get location information for CAMEL based services GMLC
Lg GMLC MSC,
SGSN
This interface is used by the GMLC to convey a location request to the MSC or SGSN
currently serving a particular target UE whose location was requested. The interface is
used by the MSC or SGSN to return location results to the GMLC. MAP
Lh GMLC HLR This interface is used by the GMLC to request the address of the visited MSC or SGSN
for a particular target UE whose location has been requested MAP
Lc, Lg, Lh Back to general map
Control plane
MAP
TCAP
SCCP
MTP3
MTP2
MTP1/L1
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Mb MGW IMS
Via the Mb reference point IPv6 network services are accessed. These IPv6 network
services are used for user data transport. Note, that GPRS provides IPv6 network
services to the UE, i.e. the GPRS Gi reference point and the IMS Mb reference point may
be the same.
RTP, RTCP
Mb Back to general map
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Mg MSC
(MGCF) CSCF
The Mg reference point allows the MGCF to forward incoming session signalling (from
the circuit switched network) to the CSCF for the purpose of interworking with circuit
switched networks.
The protocol used for the Mg reference point is SIP (as defined by RFC 3261 [61],
other relevant RFC's, and additional enhancements introduced to support 3GPP´s
needs).
SIP
Mg Back to general map
TCP SCTP UDP
IP
SIP
Control plane
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Mj MSC
(MGCF) BGCF This reference point allows the Breakout Gateway Control Function to exchange
session signalling message with the Media Gateway Control Function for the
purpose of interworking to the circuit switched networks, or for transit scenarios. SIP
Mj Back to general map
TCP SCTP UDP
IP
SIP
Control plane
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Mn MSC
(MGCF) MGW This interface provides the Media Gateway Control for interworking between the IP
Multimedia Subsystem (IMS) and CS domain (ISUP, BICC and SIP-I). 3GPP TS
29.332 GCP (H.248)
Mn Back to general map
MTP3-b
SAAL-NNI
AAL5
ATM
L1 IP
Control plane
GCP
M3UA
SCTP
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Nb MGW MGW Interface between two Media Gateways for user plane and control of user plane
connections used for circuit switched services. Q.AAL2, AAL2
Nb Back to general map
Control plane User plane
Q.2630.2
MTP3-B
SAAL-NNI
AAL5 AAL2
I.366.2
L1
ATM
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Nc MSC MSC,
TSC
Control plane interface between MSC/GMSC Servers used for circuit switched services
using BICC signaling based on ATM or IP transmission or ISUP signaling based on TDM
transmission. BICC
Nc Back to general map
ISUP
MTP3-B
SAAL-NNI
AAL5 MTP2
ATM
L1 IP MTP1/L1
Control plane
BICC
SCTP
M3UA
MTP3
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Uu RBS UE
The Uu interface is used to communicate among the UE Positioning entities associated
with the SRNC, the UEs and the stand-alone LMU. The Uu interface may pass
measurement requests and results to and from the UE or the stand-alone LMU. UE
Positioning operations at the Uu interface are generally defined in the 24- and 25-series
of 3GPP Technical Specifications. Furthermore, 25.305 describes how a stand-alone
LMU may be distinguished from a normal UE.
PDCP
Uu Back to general map
Back to SAE/LTE map
User plane
PDCP
RLC
MAC
L1
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
S1-MME eNode
B MME The eNBs are connected by means of the S1 interface to the EPC (Evolved Packet
Core), more specifically to the MME (Mobility Management Entity) by means of the S1-
MME related to control plane traffic. S1-AP
S1-MME
Back to SAE/LTE map
–Over the S1 interface the S1AP protocol is, e.g., used to:
•Facilitate a set of general E-UTRAN procedures from the
EPC such as paging-notification as defined by the
notification SAP.
•Separate each User Equipment (UE) on the protocol level
for mobile specific signalling management as defined by the
dedicated SAP.
•Transfer of transparent non-access signalling as defined in
the dedicated SAP.
•Request of various types of E-RABs through the dedicated
SAP.
•Perform the mobility function.
3GPP TS 36.41x
3GPP TS 24.301
Control plane
S1-AP
SCTP
IP
L2
L1
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
S1-U eNode
B S-GW The eNBs are connected by means of the S1 interface to the EPC (Evolved Packet
Core), more specifically to the Serving GW by means of the S1-U related to user plane
traffic. GTPv2-C
S1-U
Back to SAE/LTE map
3GPP TS 29.274
GTP tunnels are used between two nodes communicating over a GTP
based interface, to separate traffic into different communication flows.
A GTP tunnel is identified in each node with a TEID, an IP address and a
UDP port number. The receiving end side of a GTP tunnel locally assigns
the TEID value the transmitting side has to use. The TEID values are
exchanged between tunnel endpoints using GTP-C or S1-MME messages.
The criteria defining when the same or different GTP tunnels shall be used
between the two nodes differs between the control and the user plane, and
also between interfaces.
For the control plane, for each end-point of a GTP-C tunnel:
•The TEID-C shall be unique per PDN-Connection on GTP based S5 and S8
interfaces. The same tunnel shall be shared for the control messages related
to all bearers associated to the PDN-Connection. A TEID-C on the S5/S8
interface shall be released after all its associated EPS bearers are deleted.
•There shall be only one pair of TEID-Cs per UE on each of the S3, S10 and
the S16 interfaces. The same tunnel shall be shared for the control messages
related to the same UE operation. A TEID-C on the S3/S10/S16 interface shall
be released after its associated UE context is removed or the UE is detached.
•There shall be only one pair of TEID-C per UE over the S11 and the S4
interfaces. The same tunnel shall be shared for the control messages related
to the same UE operation. A TEID-C on the S11/S4 interface shall be released
after all its associated EPS bearers are deleted
For GTP-U, a TEID-U is used according to 3GPP TS 29.281 [13].
NOTE: GTP-U is based on GTP version 1 (GTPv1).
User plane
GTP-U
UDP
IP
L2
L1
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
SGs MSC MME
It is the reference point between the MME and MSC server. The SGs reference point is
used for the mobility management and paging procedures between EPS and CS
domain, and is based on the Gs interface procedures. The SGs reference point is also
used for the delivery of both mobile originating and mobile terminating SMS. Additional
procedures for alignment with the Gs reference point are not precluded.
The SGs interface is used to provide Fallback for Location Services (LCS) and Call
Independent Supplementary Services (SS).
The signalling on this interface uses SCTP.
SGsAP (BSSAP+)
SGs
Back to SAE/LTE map
Control plane
SGsAP(BSSAP+)
SCTP
IP
L2
L1
3GPP TS 23.272
The SGs interface functionality is based on the
mechanisms specified for the Gs interface
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
Sv MSC MME The interface provides SRVCC support for functions like sending Forward Relocation
Message between MME or SGSN and 3GPP MSC Server. GTPv2-C
Sv
Back to SAE/LTE map
Control plane
GTP
UDP
IP
L2
L1
3GPP TS 29.280
3GPP TS 23.216
3GPP TS 29.274
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
S6a MME HLR/H
SS
This interface is used to exchange the data related to the location of the mobile station
and to the management of the subscriber. The main service provided to the mobile
subscriber is the capability to transfer packet data within the whole service area. The
MME informs the HSS of the location of a mobile station managed by the latter. The
HSS sends to the MME all the data needed to support the service to the mobile
subscriber. Exchanges of data may occur when the mobile subscriber requires a
particular service, when he wants to change some data attached to his subscription or
when some parameters of the subscription are modified by administrative means.
Signalling on this interface uses Diameter S6a/S6d Application
Diameter
S6a
Back to SAE/LTE map
3GPP TS 29.272
3GPP TS 23.401
Control plane
Diameter
SCTP
IP
L2
L1
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
S6d SGSN HLR/H
SS
This interface is used to exchange the data related to the location of the mobile station
and to the management of the subscriber. The main service provided to the mobile
subscriber is the capability to transfer packet data within the whole service area. The
SGSN informs the HSS of the location of a mobile station managed by the latter. The
HSS sends to the SGSN all the data needed to support the service to the mobile
subscriber. Exchanges of data may occur when the mobile subscriber requires a
particular service, when he wants to change some data attached to his subscription or
when some parameters of the subscription are modified by administrative means.
Signalling on this interface uses Diameter S6a/S6d Application
Diameter
S6d
Back to SAE/LTE map
Control plane
Diameter
SCTP
IP
L2
L1
3GPP TS 29.272
3GPP TS 23.401
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
S5/S8 S-GW PDN-
GW
These interfaces are between S-GW and PDN-GW, provides support for functions for
packet data services towards end users during roaming and non-roaming cases (i.e. S8
is the inter PLMN variant of S5). GTPv2-C
S5, S8
Back to SAE/LTE map
Control plane
GTP
UDP
IP
L2
L1
3GPP TS 29.274
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
S13 MME EIR This interface is used between MME and EIR to exchange data, in order that the EIR can
verify the status of the IMEI retrieved from the Mobile Station Diameter
S13
Back to SAE/LTE map
Control plane
Diameter
SCTP
IP
L2
L1
3GPP TS 29.272
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
S4 SGSN S-GW This interface 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 GTPv2-C
S4
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Control plane
GTP
UDP
IP
L2
L1
3GPP TS 29.274
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
S12 S-GW RNC
Interface 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
GTPv2-C
S12
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3GPP TS 29.274
User plane
GTP-U
UDP
IP
L2
L1
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
S2a Non-
3GPP
access
PDN-
GW It provides the user plane with related control and mobility support between trusted non
3GPP IP access and the Gateway
S2b
Non-
3GPP
access
PDN-
GW It provides the user plane with related control and mobility support between ePDG and
the Gateway. It’s related to non trusted non-3GPP access
S2c UE PDN-
GW
It provides the user plane with related control and mobility support between UE and the
Gateway. This reference point is implemented over trusted and/or untrusted non-3GPP
Access and/or 3GPP access.
S2a, S2b, S2c
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3GPP TS 29.275
3GPP TS 23.402
IPv4/IPv6 IPv4
Tunneling Tunneling
PMIPv4
IPv4
L2
L1
IPv4/IPv6
PMIPv6
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
S6b PDN-
GW AAA
It is the interface between PDN GW and 3GPP AAA server/proxy for mobility related
authentication and authorization. This interface may also be used to retrieve and request
storage of mobility parameters, such as the PDN GW Identity. It may also be used to
retrieve static QoS profile for a UE for non-3GPP access in case dynamic PCC is not
supported
Diameter
S6b
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3GPP TS 29.273
Control plane
Diameter
SCTP
IP
L2
L1
3GPP TS 23.402
The S6b reference point shall be based on
Diameter, as defined in IETF RFC 3588 [7] and
contain the following additions and extensions:
–IETF RFC 4005, which defines a Diameter
protocol application used for Authentication,
Authorization and Accounting (AAA) services in
the Network Access Server (NAS) environment.
–IETF Draft draft-korhonen-dime-pmip6 , which
defines a Diameter extensions and application
for PMIPv6 MAG to AAA and LMA to AAA
interfaces.
–IETF Draft draft-ietf-dime-qos-attributes , which
defines attribute value pairs to convey QoS
information between Diameter peers.
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
SWa
Non-
trusted
non-
3GPP
access
AAA It enables support for the Untrusted non-3GPP IP Access with the 3GPP AAA
Server/Proxy and transports access authentication, authorization and charging-related
information in a secure manner Diameter
STa
Truste
d non-
3GPP
access
AAA It connects the Trusted non-3GPP IP Access with the 3GPP AAA Server/Proxy and
transports access authentication, authorization, mobility parameters and charging-related
information in a secure manner Diameter
SWa, STa
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3GPP TS 29.273
3GPP TS 23.402
Control plane
Diameter
SCTP
IP
L2
L1
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
SWn
Non-
trusted
non-
3GPP
access
ePDG This is the reference point between the Untrusted Non-3GPP IP Access and the ePDG.
Traffic on this interface for a UE-initiated tunnel has to be forced towards ePDG Diameter
SWn
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3GPP TS 29.273
3GPP TS 23.402
Control plane
Diameter
SCTP
IP
L2
L1
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
SGi PDN-
GW Ext
PDN
Interface between the PDN-GW and a packet data network. It 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 -
SGi
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3GPP TS 29.061
Mobile Interface - ankitsaxena
Interface
Between
Description Top Protocols
Node Node
X2 eNode
B eNode
B This is a logical interface between two eNBs. Whilst logically representing a point to point
link between eNBs, the physical realization need not be a point to point link X2AP
X2
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Control plane
X2-AP
SCTP
IP
L1
–The list of functions on the X2 interface is the
following:
•Intra LTE-Access-System Mobility Support for ECM-
CONNECTED UE:
–Context transfer from source eNB to target eNB
–Control of user plane transport bearers between source eNB and
target eNB
–Handover cancellation
–UE context release in source eNB
•Load Management
•Inter-cell Interference Coordination
–Uplink Interference Load Management
•General X2 management and error handling functions:
–Error indication
–Reset
•Application level data exchange between eNBs
•Trace functions
Mobile Interface - ankitsaxena
Node Description
Base Station Controller
The Base Station Controller (BSC) area is an area of radio coverage consisting of one or more cells
controlled by one BSC. The boundaries of a BSC area and a location area are independent; a
location area may span the boundary between BSC area and a BSC area may span the boundary
between location areas
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Node Description
Radio Network
Controller
The Radio Network Controller (RNC) area is an area of radio coverage consisting of one or more cells
controlled by one RNC. The boundaries of a RNC area and a location area are independent; a
location area may span the boundary between RNC area and a RNC area may span the boundary
between location areas
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Mobile Interface - ankitsaxena
Node Description
Home Subscriber Server
The HSS is the master database for a given user. It is the entity containing the subscription-related
information to support the network entities actually handling calls/sessions.
A Home Network may contain one or several HSSs: it depends on the number of mobile subscribers,
on the capacity of the equipment and on the organisation of the network.
As an example, the HSS provides support to the call control servers in order to complete the
routing/roaming procedures by solving authentication, authorisation, naming/addressing resolution,
location dependencies, etc.
The HSS is responsible for holding the following user related information:
- User Identification, Numbering and addressing information;
- User Security information: Network access control information for authentication and authorization;
- User Location information at inter-system level: the HSS supports the user registration, and stores
inter-system location information, etc.;
- User profile information.
The HSS also generates User Security information for mutual authentication, communication integrity
check and ciphering.
The HSS may integrate heterogeneous information, and enable enhanced features in the core
network to be offered to the application & services domain, at the same time hiding the heterogeneity.
The HSS consists of the following functionalities:
- IP multimedia functionality to provide support to control functions of the IM subsystem such as the
CSCF. It is needed to enable subscriber usage of the IM CN subsystem services. This IP multimedia
functionality is independent of the access network used to access the IM CN subsystem.
- The subset of the HLR/AUC functionality required by the PS Domain (GPRS and EPC).
- The subset of the HLR/AUC functionality required by the CS Domain, if it is desired to enable
subscriber access to the CS Domain or to support roaming to legacy GSM/UMTS CS Domain
networks
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Mobile Interface - ankitsaxena
Node Description
Home Location Register
The HLR can be considered a subset of the HSS that holds the following functionality:
- The functionality required to provide support to PS Domain entities such as the SGSN, MME and
GGSN, through the Gr, S6a, S6dand Gc interfaces and the 3GPP AAA Server for EPS in case of non-
3GPP access via SWx and for the I-WLAN through the D'/Gr' interface. It is needed to enable
subscriber access to the PS Domain services.
- The functionality required to provide support to CS Domain entities such as the MSC/MSC server
and GMSC/GMSC server, through the C and D interfaces. It is needed to enable subscriber access to
the CS Domain services and to support roaming to legacy GSM/UMTS CS Domain networks
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Mobile Interface - ankitsaxena
Node Description
Authentication Centre
The AuC can be considered a subset of the HSS that holds the following functionality for the CS
Domain and PS Domain:
- The AuC is associated with an HLR and stores an identity key for each mobile subscriber registered
with the associated HLR. This key is used to generate security data for each mobile subscriber:
- data which are used for mutual authentication of the International Mobile Subscriber Identity (IMSI)
and the network;
- a key used to check the integrity of the communication over the radio path between the mobile
station and the network;
- a key used to cipher communication over the radio path between the mobile station and the network.
- The AuC communicates only with its associated HLR over a non-standardised interface denoted the
H-interface. The HLR requests the data needed for authentication and ciphering from the AuC via the
H-interface, stores them and delivers them to the VLR and SGSN and MME which need them to
perform the security functions for a mobile station
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Mobile Interface - ankitsaxena
Node Description
Visitor Location
Register
A mobile station roaming in an MSC area or within a GERAN/UTRAN pool-area is controlled by a
Visitor Location Register. When a Mobile Station (MS) enters a new location area it starts a
registration procedure. An MSC in charge of that area notices this registration and transfers to a
Visitor Location Register the identity of the location area where the MS is situated. If this MS is not yet
registered in the VLR, the VLR and the HLR exchange information to allow the proper handling of CS
calls involving the MS.
A VLR may be in charge of one or several MSC areas.
The VLR contains also the information needed to handle the calls set-up or received by the MSs
registered in its data base (for some supplementary services the VLR may have to obtain additional
information from the HLR). The following elements are included:
- the International Mobile Subscriber Identity (IMSI);
- the Mobile Station International ISDN number (MSISDN);
- the Mobile Station Roaming Number (MSRN), see TS 23.003 [3] for allocation principles;
- the Temporary Mobile Station Identity (TMSI), if applicable;
- the Local Mobile Station Identity (LMSI), if used;
- the location area where the mobile station has been registered;
- the identity of the SGSN where the MS has been registered. Only applicable to PLMNs supporting
GPRS and which have a Gs interface between MSC/VLR and SGSN;
- the last known location and the initial location of the MS;
- the identity of the MME where the MS has been registered. Only applicable to PLMNs supporting
EPC and CS Fallback and which have a SGs interface between MSC/VLR and MME
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Mobile Interface - ankitsaxena
Node Description
Equipment Identity
Register
The Equipment Identity Register (EIR) in the GSM system is the logical entity which is responsible for
storing in the network the International Mobile Equipment Identities (IMEIs), used in the
GERAN/UTRAN/E-UTRAN system.
The equipment is classified as "white listed", "grey listed", "black listed" or it may be unknown as
specified in TS 22.016 [2] and TS 29.002].
This functional entity contains one or several databases which store(s) the IMEIs used in the system.
The mobile equipment may be classified as "white listed", "grey listed" and "black listed" and therefore
may be stored in three separate lists.
An IMEI may also be unknown to the EIR.
An EIR shall as a minimum contain a "white list" (Equipment classified as "white listed")
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Mobile Interface - ankitsaxena
Node Description
Mobile Switching Centre
The Mobile-services Switching Centre (MSC) constitutes the interface between the radio system and
the fixed networks. The MSC performs all necessary functions in order to handle the circuit switched
services to and from the mobile stations.
In order to obtain radio coverage of a given geographical area, a number of BSS and/or RNS are
normally required; i.e. each MSC would thus have to interface to one or more BSS(s) and/or RNS(s).
In addition several MSCs may be required to cover a country.
When Intra Domain Connection of RAN Nodes to Multiple CN Nodes is applied, all the MSCs serving
a pool-area share the responsibility to serve the MSs located in the pool-area. All these MSCs
interface to all the BSS(s) and/or RNS(s) forming the pool-area.
The Mobile-services Switching Centre is an exchange, which performs all the switching and signalling
functions for mobile stations located in a geographical area designated as the MSC area. When Intra
Domain Connection of RAN Nodes to Multiple CN Nodes is applied, one or more MSCs serve a pool-
area, but each individual MS is served by only one out of these MSCs, as described in TS 23.236 .
The main difference between a MSC and an exchange in a fixed network is that the MSC has to take
into account the impact of the allocation of radio resources and the mobile nature of the subscribers
and has to perform in addition
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Node Description
MSC Server
The MSC Server mainly comprises the call control (CC) and mobility control parts of a MSC.
The MSC Server is responsible for the control of mobile originated and mobile terminated CC CS
Domain calls. It terminates the user-network signalling and translates it into the relevant network –
network signalling. The MSC Server also contains a VLR to hold the mobile subscriber's service data
and CAMEL related data.
The MSC Server controls the parts of the call state that pertain to connection control for media
channels in a CS-MGW.
An MSC Server which has been enhanced for SRVCC provides the following functions as needed for
support of SRVCC according to TS 23.216:
- Handling the Relocation Preparation procedure requested for the voice component from MME via Sv
interface;
- Invoking the session transfer procedure from IMS to CS ;
- Coordinating the CS Handover and session transfer procedures;
- Handling the MAP_Update_Location procedure without it being triggered from the UE.
If a MSC Server is enhanced for IMS Centralized Services (as defined in TS 23.292), it is responsible
for the CS to IMS interworking, and it terminates the user-network signalling received over the CS
access (A/Iu and E interface) and translates it into SIP signalling in IMS and vice versa
Mobile Interface - ankitsaxena
Node Description
Gateway MSC
If a network delivering a call to the PLMN cannot interrogate the HLR, the call is routed to an MSC.
This MSC will interrogate the appropriate HLR and then route the call to the MSC where the mobile
station is located. The MSC which performs the routing function to the actual location of the MS is
called the Gateway MSC (GMSC).
The acceptance of an interrogation to an HLR is the decision of the operator.
The choice of which MSCs can act as Gateway MSCs is for the operator to decide (i.e. all MSCs or
some designated MSCs).
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Mobile Interface - ankitsaxena
Node Description
Serving GPRS Support
Node
The location register function in the SGSN stores two types of subscriber data needed to handle
originating and terminating packet data transfer:
- subscription information:
- the IMSI;
- one or more temporary identities;
- zero or more PDP addresses.
- location information:
- depending on the operating mode of the MS, the cell or the routeing area where the MS is
registered;
- the VLR number of the associated VLR (if the Gs interface is implemented);
- the GGSN address of each GGSN for which an active PDP context exists
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Mobile Interface - ankitsaxena
Node Description
Gateway GPRS Support
Node
The location register function in the GGSN stores subscriber data received from the HLR and the
SGSN. There are two types of subscriber data needed to handle originating and terminating packet
data transfer:
- subscription information:
- the IMSI;
- zero or more PDP addresses.
- location information:
- the SGSN address for the SGSN where the MS is registered
GGSN Back to general map
Mobile Interface - ankitsaxena
Node Description
Mobility Management
Entity
MME is the control plane entity within EPS supporting functions as listed below. For detailed
functional role of MME, see specifications TS 23.401, TS 23.402 and TS 36.300.
Mobility Management,
- NAS signalling and security;
- Inter CN node signalling for mobility between 3GPP access networks;
- Tracking Area list management;
- PDN GW and Serving GW selection;
- SGSN selection for handovers to 2G or 3G 3GPP access networks;
- Roaming ;
- Authentication;
- Bearer management functions including dedicated bearer establishment.
- Lawful Interception of signalling traffic.
In order to support 3GPP2 access, MME supports:
- HRPD access node selection and maintenance for handovers to HRPD;
- Transparent transfer of HRPD signalling messages and transfer of status information between E-
UTRAN and HRPD access;
The procedures for information transfer between the SGSN, the MME and the HSS are defined in TS
23.401 and TS 23.060.
The CS fallback enabled MME supports the following additional functions according to TS 23.272 :
- Deriving a VLR number and LAI out of the TAI
- Maintaining of SGs association towards MSC/VLR for EPS/IMSI attached UE
- Initiating IMSI detach at EPS detach
- Initiating paging procedure towards eNodeB when MSC pages the UE for CS services
- Supporting SMS procedures for CS Fallback.
- Support CS Fallback interface and related functions for 1xRTT CDMA access.
When the MME supports the interworking to 3GPP CS, the MME supports the following functions as
specified in TS 23.216:
- Performing the PS bearer splitting function by separating the voice PS bearer from the non-voice PS
bearers.
- Handling the non-voice PS bearers handover with the target cell as according to Inter RAT handover
procedure as defined in TS 23.401.
- Initiating the SRVCC handover procedure for handover of the voice component to the target cell.
- Coordinating PS handover and SRVCC handover procedures when both procedures are performed,
- support interworking and SRVCC related functions for 1xRTT CDMA access
MME
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Mobile Interface - ankitsaxena
Node Description
Serving GW
The Serving GW is the gateway which terminates the interface towards E-UTRAN.
For each UE associated with the EPS, at a given point of time, there is a single Serving GW. For
detailed S-GW functions, see TS 23.401 [76] and TS 23.402.
Connectivity to a GGSN is not supported.
The functions of the Serving GW include:
- the local Mobility Anchor point for inter-eNodeB handover;
- Mobility anchoring for inter-3GPP mobility;
- ECM-IDLE mode downlink packet buffering and initiation of network triggered service request
procedure;
- Lawful Interception;
- Packet routeing and forwarding;
- Transport level packet marking in the uplink and the downlink;
- Accounting on user and QCI granularity for inter-operator charging;
- A local non-3GPP anchor for the case of roaming when the non-3GPP IP accesses connected to the
VPLMN;
- Event reporting (change of RAT, etc.) to the PCRF;
- Uplink and downlink bearer binding towards 3GPP accesses as defined in TS 23.203;
- Uplink bearer binding verification with packet dropping of "misbehaving UL traffic";
- Mobile Access Gateway (MAG) functions if PMIP-based S5 or S8 is used;
- Support necessary functions in order for enabling GTP/PMIP chaining functions
Serving GW
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Mobile Interface - ankitsaxena
Node Description
Packet Data Network
GW
The PDN GW is the gateway which terminates the SGi interface towards the PDN.
If a UE is accessing multiple PDNs, there may be more than one PDN GW for that UE, however a mix
of S5/S8 connectivity and Gn/Gp connectivity is not supported for that UE simultaneously.
The P GW provides PDN connectivity to both GERAN/UTRAN only UEs and E UTRAN capable UEs
using any of E UTRAN, GERAN or UTRAN. The P GW provides PDN connectivity to E UTRAN
capable UEs using E UTRAN only over the S5/S8 interface. The P¬GW may also provide PDN
connectivity to UEs using non-3GPP access networks with the procedures defined in TS 23.402.
For detailed PDN-GW functions, see TS 23.401 [76] and TS 23.402.
PDN GW functions include:
- Per-user based packet filtering (by e.g. deep packet inspection);
- Lawful Interception;
- UE IP address allocation;
- Transport level packet marking in the uplink and downlink, e.g. setting the DiffServ Code Point,
based on the QCI of the associated EPS bearer;
- UL and DL service level charging, gating control, rate enforcement as defined in TS 23.203;
- UL and DL rate enforcement based on APN-AMBR;
- DL rate enforcement based on the accumulated MBRs of the aggregate of SDFs with the same GBR
QCI (e.g. by rate policing/shaping);
- DHCPv4 (server and client) and DHCPv6 (client and server) functions;
Additionally the PDN GW includes the following functions for the GTP-based S5/S8:
- UL and DL bearer binding as defined in TS 23.203;
- UL bearer binding verification;
The PDN GW functions also includes user plane anchor for mobility between 3GPP access and non-
3GPP access. It supports:
- A LMA function, if PMIP-based S5 or S8, or if S2a or S2b is used;
- A DSMIPv6 Home Agent, if S2c is used;
- Allocation of GRE key, which is used to encapsulate uplink traffic to the PDN GW on the PMIP-
based S5/S8, or S2a or S2b interface;
- A MIPV4 Home Agent, if S2a with MIPv4 FA CoA mode is used
PDN GW
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Mobile Interface - ankitsaxena
Node Description
Trusted and Untrusted Non-3GPP Access Networks are IP access networks that use access
technology whose specification is out of the scope of 3GPP.
Whether a Non-3GPP IP access network is Trusted or Untrusted is not a characteristic of the access
network.
In non-roaming scenario it is the HPLMN's operator decision if a Non-3GPP IP access network is
used as Trusted or Untrusted Non-3GPP Access Network.
In roaming scenario, the HSS/3GPP AAA Server in HPLMN makes the final decision of whether a
Non-3GPP IP access network is used as Trusted or Untrusted non-3GPP Access Network. The
HSS/3GPP AAA Server may take the VPLMN's policy and capability returned from the 3GPP AAA
Proxy or roaming agreement into account
Non-3GPP Access
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Mobile Interface - ankitsaxena
Node Description
Evolved Packet Data
Gateway
The functionality of ePDG includes the following:
- Functionality defined for the PDG in TS 23.234 for the allocation of a remote IP address as an IP
address local to the ePDG which is used as CoA when S2c is used;
- Functionality for transportation of a remote IP address as an IP address specific to a PDN when S2b
is used;
- Routing of packets from/to PDN GW (and from/to Serving GW if it is used as local anchor in VPLMN)
to/from UE;
- De-capsulation/Encapsulation of packets for IPSec and PMIP tunnels (the latter only if network
based mobility (S2b) is used);
- Mobile Access Gateway (MAG) if network based mobility (S2b) is used;
- Tunnel authentication and authorization (termination of IKEv2 signalling and relay via AAA
messages);
- Local mobility anchor within untrusted non-3GPP access networks using MOBIKE (if needed);
- Transport level packet marking in the uplink;
- Enforcement of QoS policies based on information received via AAA infrastructure;
- Lawful Interception
ePDG
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Mobile Interface - ankitsaxena
Node Description
Authentication
Authorization
The 3GPP AAA Server is located at the HPLMN and provides support for non-3GPP Access users
with services like Authentication, Authorisation and location management services in order to get
access to EPS. It also contains necessary user related information in order to grant access to non-
3GPP access. It also coordinates the information needed to support mobility between 3GPP and non-
3GPP accesses such as coordination of PDN-GW information. It interacts with HSS to maintain
consistent information for users supporting mobility and service continuity between 3GPP and non-
3GPP access. For details, see TS 23.402
AAA Server
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Mobile Interface - ankitsaxena
Node Description
Mobile Station
The mobile station consists of the physical equipment used by a PLMN subscriber; it comprises the
Mobile Equipment (ME) and the Subscriber Identity Module (SIM), called UMTS Subscriber Identity
Module (USIM) for Release 99 and following. The ME comprises the Mobile Termination (MT) which,
depending on the application and services, may support various combinations of Terminal Adapter
(TA) and Terminal Equipment (TE) functional groups
MS Back to general map
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Mobile Interface - ankitsaxena
Node Description
User Equipment
The User Equipment Allows a user access to network services. For the purpose of 3GPP
specifications the interface between the UE and the network is the radio interface. A User Equipment
can be subdivided into a number of domains, the domains being separated by reference points.
Currently the User Equipment is subdivided into the UICC domain and the ME Domain. The ME
Domain can further be subdivided into one or more Mobile Termination (MT) and Terminal Equipment
(TE) components showing the connectivity between multiple functional groups
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Mobile Interface - ankitsaxena
Node Description
Gateway Mobile
Location Centre
The Gateway Mobile Location Centre (GMLC) is the first node an external Location Application
accesses in the GSM PLMN. The GMLC performs registration authorization and requests routing
information from the HLR. There may be more than one GMLC in a PLMN
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Mobile Interface - ankitsaxena
Node Description
GSM Service Switching
Function
A functional entity that interfaces the MSC/GMSC to the gsmSCF. The concept of the gsmSSF is
derived from the IN SSF, but uses different triggering mechanisms because of the nature of the
mobile network
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Mobile Interface - ankitsaxena
Node Description
Call Session Control
Function
The CSCF can act as Proxy CSCF (P CSCF), Serving CSCF (S CSCF), Emergency CSCF (E CSCF),
or Interrogating CSCF (I CSCF). The P CSCF is the first contact point for the UE within the IM
subsystem (IMS); the S CSCF actually handles the session states in the network; the E CSCF
handles certain aspects of emergency sessions such as routing an emergency request to the correct
emergency centre or PSAP; the I CSCF is mainly the contact point within an operator's network for all
IMS connections destined to a subscriber of that network operator, or a roaming subscriber currently
located within that network operator's service area
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Mobile Interface - ankitsaxena
Node Description
Media Gateway Control
Function
The MGCF:
- Controls the parts of the call state that pertain to connection control for media channels in an IMS-MGW.
- Communicates with CSCF, BGCF, and circuit switched network entities.
- Determines the next hop depending on the routing number for incoming calls from legacy networks.
- Performs protocol conversion between ISUP/TCAP and the IM subsystem call control protocols.
- Out of band information received in MGCF may be forwarded to CSCF/IMS-MGW
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Mobile Interface - ankitsaxena
Node Description
Multimedia Resource
Function Controller
The MRFC:
- Controls the media stream resources in the MRFP.
- Interprets information coming from an AS and S CSCF (e.g. session identifier) and control MRFP accordingly.
- Generates CDRs .
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Mobile Interface - ankitsaxena
Node Description
Multimedia Resource
Function Processor
The MRFP:
- Controls bearers on the Mb reference point.
- Provides resources to be controlled by the MRFC.
- Mixes incoming media streams (e.g. for multiple parties).
- Sources media streams (for multimedia announcements).
- Processes media streams (e.g. audio transcoding, media analysis).
- Floor Control (i.e. manage access rights to shared resources in a conferencing environment).
MRFP Back to general map
Mobile Interface - ankitsaxena
Node Description
Policy and Charging
Rules Function
The Policy and Charging Rules Function (PCRF) acts as a policy decision point for policy and
charging control of service data flows and IP bearer resources. The PCRF selects and provides the
applicable policy and charging control decision to the PCEF.
When Gxx interface applies, the PCRF maintains the correlation between the GW control session and
the IP-CAN session. The PCRF also acts as an information exchange point between BBERF and
PCEF to forward event triggers, which can't be transferred directly between the BBERF and PCEF
PCRF is the policy and charging control element. PCRF functions are described in more detail in TS
23.203.
In non-roaming scenario, there is only a single PCRF in the HPLMN associated with one UE's IP-CAN
session.
In a roaming scenario with local breakout of traffic and/or when a Gxx interface applies there are two
PCRFs associated with one UE's IP-CAN session:
- H-PCRF that resides within the H-PLMN;
- V-PCRF that resides within the V-PLMN.
A single logical PCRF entity may be deployed by means of multiple and separately addressable
PCRFs in the PLMN. In this case, the PCRF discovery and selection is enabled by Diameter Routing
Agency (DRA).
PCRF
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Node Description
Enhanced Node B
An eNB is a logical network component which serves one or more E-UTRAN cells.
The Evolved UTRAN (E-UTRAN) consists of eNBs, providing the E-UTRA user plane
(PDCP/RLC/MAC/PHY) and control plane (RRC) protocol terminations towards the UE. The eNBs can
be interconnected with each other by means of the X2 interface. The eNBs are connected by means
of the S1 interface to the EPC (Evolved Packet Core), more specifically to the MME (Mobility
Management Entity) by means of the S1-MME and to the Serving Gateway (S-GW) by means of the
S1-U interface. The S1 interface supports a many-to-many relation between MMEs / Serving
Gateways and eNBs
eNodeB
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Node Description
Breakout Gateway
Control Function
The Breakout Gateway control function (BGCF) determines the next hop for routing the SIP message.
This determination may be based on information received in the signalling protocol, administrative
information, and/or database access. For PSTN /CS Domain terminations, the BGCF determines the
network in which PSTN/CS Domain breakout is to occur and - within the network where the breakout
is to occur - selects the MGCF.
Details are described in TS 23.228
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Node Description
Operation and Support
System
Operation and Support System (OSS) is the system to support the activities performed in an OMC
and/or NMC. The network operator monitors and controls the network through OSS which offers cost
effective support of centralized, regional and local operation and maintenance activities
OSS Back to general map
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Node Description
Media Gateway
The Media Gateway function operates on the user plane in order to enable interworking between
between different transport domain. The MSC Server controls the Media Gateway function. The
Media Gateway function has 2 functional layer:
- Media Stream provides the devices needed to manipulate the user data according to the circuit-
based service being used.
- Transport provides the switching of the user plane and bearer control for the interworking between
different transport domain
MGW Back to general map
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Node Description
gsmSSF-gsmSCF This interface is used by the gsmSCF to control a call in a certain gsmSSF and to request the
gsmSSF to establish a connection with a gsmSRF. Relationships on this interface are opened as a
result of the gsmSSF sending a request for instructions to the gsmS
gsmSSF-gsmSCF Back to general map
MTP3-b
SAAL-NNI
AAL5
ATM
MTP1/L1 L1 IP
MTP3
M3UA
MTP2
SCTP
Control plane
CAP/INAP
TCAP
SCCP
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Node Description
gsmSCF-HLR
This interface is used by the gsmSCF to request information from the HLR. As a network operator
option the HLR may refuse to provide the information requested by the gsmSCF.
This interface is also used for USSD operations, both for gsmSCF-initiated dialogues and MS-initiated
dialogues (relayed via HLR). It is a network operator option whether to support or not USSD
operations on this interface
gsmSCF-HLR Back to general map
MTP3-b
SAAL-NNI
AAL5
ATM
MTP1/L1
L1
IP
MTP3
MTP2
M3UA
SCTP
SCCP
MAP
Control plane
TCAP
Mobile Interface - ankitsaxena
Document title Web link
Technical Specification Group Services and Systems Aspects; Network Architecture 3GPP TS 23.002
Protocol Specification Survey 109 43-HSD 101 13/5
Ericsson Standardization and Industry Initiatives Standardization and Industry Initiatives
ITU-T ITU-T
IETF RFC page
3GPP 3GPP specs
ETSI ETSI specs
Ericsson Statement of Compliance 3GPP Ericsson SoCs
Useful Links
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