# Glossary

1xEV-DO. See EV-DO.

1xEV-DV. The third phase of CDMA2000 following 1xEV-DO deployment. 1xEV-DV stands for 1x Evolution - Data Voice, and is characterized by a maximum data rate of 5.2 Mbps and the ability to support wireless Voice over IP (VoIP) services.

1xRTT. The first phase of CDMA2000, characterized by the ability to support a maximum data rate of 1.44 Kbps. 1xRTT stands for 1x, denoting the one radio channel of 1.25 MHz in Radio Transmission Technology.

2G. The second generation of wireless technology that was characterized by its use of digital transmissions rather than analog methods. Radio bandwidth is used for data transmissions. Data transmissions are limited to a maximum rate of 1.44 Kbps for CDMA 2G services (9.6 Kbps for GSM 2G). Radio bandwidth is consumed whenever the Mobile Node (MN) is connected to the Internet, regardless of whether it is receiving or transmitting data. This is based on the IS-95A standard for CDMA.

2.5G. An evolutionary step between 2G and 3G wireless services wherein two enhancements were introduced over 2G. The first is that the MN only consumes radio bandwidth when data is being transmitted or received. The second is that the maximum data rate increased to approximately 64 Kbps. Most 2.5G services only support data rates between 1.15 Kbps and 384 Kbps. This is based on the IS-95B standard for CDMA.

3G. The third generation of wireless technology, wherein data services are packetized, with speeds up to 2 Mbps. Based on the CDMA2000 standards.

3GPP. Third Generation Partnership Project. A group of organizational partners from ETSI, TIA/EIA, and other standardization bodies who are working together to define the evolution of GSM-based wireless communication core networks.

3GPP2. Third Generation Partnership Project 2. A second group of organizational partners from ETSI, TIA/EIA, and other standardization bodies who are working together to define the evolution of CDMA-based wireless communication networks

A

A10. The subscriber data portion of the R-P interface (based on GRE as defined in RFC-2784 and IP Encapsulation Within IP as defined in RFC-2003).

A11. The control portion of the R-P interface (based on Mobile IPv4 as defined in RFC-2002).

A11 Manager. A task within the system that controls the signalling de-multiplexing tasks of the A11 interface used for wireless communications.

AA-A. Authentication/Authorization Answer.

AA-R. Authentication/Authorization Request.

AAA. Authentication, Authorization, and Accounting. The security and billing methodology used by operators to ensure a user's identity and to determine their network usage so that they are properly billed. Often interchanged with the Remote Authentication Dial In User Service (RADIUS) protocols.

AAA Manager. Accounting, Authentication, and Authorization Manager. software task that performs all AAA protocol operations and functions for subscribers and context-level administrative users within the system.

ACL. Access Control List. A filtering mechanism used by many access IP routers that controls which traffic may be received or transmitted on an interface or port.

ACO. Alarm Cut Off. This is a toggle switch used to temporarily disable a central office alarm that occurs on a specific network device.

ACR. Active Charging Record.

Acceptable Cell. This is a cell that the MS may camp on to make emergency calls. It must satisfy criteria which are defined for A/Gb mode in 3GPP TS 43.022 and for Iu mode in 3GPP TS 25.304.

Access Technology. The access technology associated with a PLMN. The MS uses this information to determine what type of radio carrier to search for when attempting to select a specific PLMN (e.g., GSM, UTRAN, GSM COMPACT or E-UTRAN). A PLMN may support more than one access technology.

Address resolution. The process of determining the link-layer address of a node whose network-layer address is known.

AF. See Application Function

Aggregate Maximum Bit Rate. The maximum bit rate that limits the aggregate bit rate of a set of non-GBR bearers of a UE. The label (E-UTRAN only) indicates this subclause or paragraph applies only if E-UTRAN is used as current radio access network.

AH. See Authentication Header.

AKA. Authentication and Key Agreement.

Allowable PLMN. In the case of a MS operating in MS operation mode A or B, this is a PLMN which is not in the list of "forbidden PLMNs" in the MS. In the case of a MS operating in MS operation mode C, this is a PLMN which is not in the list of "forbidden PLMNs" or in the list of "forbidden PLMNs for GPRS service" in the MS.

Allowed CSG List.A list of CSG IDs stored in the UE. A UE is able to access only those CSG cells that have a CSG ID in this list.

Application Function.An Applciation Function is an element offering applications that use IP bearer resources. The AF is capable of communicating with the CRF to transfer dynamic charging rules related service information. One example of an AF is the P-CSCF of the IM CN subsystem.

APN. Access Point Name. The APN is a logical name for a packet data network and/or a service that the GGSN supports access to.

APS. Automatic Protection Switching. A means of achieving network redundancy through using automatic switching mechanisms to switch from a primary circuit to a pre-defined secondary circuit.

ARP. Address Resolution Protocol. A standard protocol for performing address resolution between IP addresses and various link-layer addresses.

Agent advertisement. The procedure by which a mobility agent becomes known to the mobile node.

Agent discovery. The process by which a mobile node can obtain the IP address of a home agent or foreign agent, depending upon whether the mobile node is home or away from home. Agent discovery occurs when a mobile node receives an agent advertisement, either as a result of periodic broadcast or in response to a solicitation.

ARQ. Automatic Repeat Request. A link layer may automatically retransmit packets that were not correctly received by the next hop link layer. This improves the robustness of the packet delivery, but comprises the latency and packet overhead.

AT. Access Terminal

ATM. Asynchronous Transfer Mode. A connection-oriented data link layer protocol used in cell relay/packet switch networks.

Authentication header (AH). Part of IP Security (IPSec) specification. Other IPSec header mechanisms include Diffie-Hellman, DES, 3DES, and others.

Authorization Token. The authorization token consists of the AF session identifier as well as the PDF identifier. The AF session identifier is assigned by the P-CSCF on successful IMS session establishment. The authorization token is sent to the UE by P-CSCF as part of the session establishment. The UE passes the authorization token in the binding information to the AGW. AGW uses the authorization token to get the PDF to be communicated for policy authorization and the session identifier is used for the authorization request to indicate the session to which authorization event belongs.

Automatic home agent discovery. The process by which a mobile node can obtain the IP address of a home agent on its home network, involving the transmission of a registration request to the subnet broadcast address of its home network.

AVP. Attribute -Value Pair.It corresponds to an Information Element in an AAA message.

B

Base Station. An entity in the public radio telecommunications system used for bi-directional radio communications with mobile stations or mobile nodes.

BBERF. Bearer Binding and Event Reporting Function (on HSGW or S-GW).

BCE. Binding Cache Entry (associated with PBU).

BE. Best Effort.

BGP. A routing protocol used in interdomain routing in large networks to maintain integrity of the network. It allows the routers to exchange only pre-specified information with pre-specified routers in other domains.

BHSA. Busy Hour Session Attempts. A measure of dynamic sessions (traffic calls) that can be attempted in an average Busy Hour.

BHSC. Busy Hour Session Completion. A measure of dynamic sessions (traffic calls) that can be completed in an average Busy Hour.

Binding. The triplet of numbers that contains the mobile node's home address, its care-of address, and the registration lifetime-how long the mobility agents may use the binding. Binding, within the system, creates the association of a virtual interface to a physical port on the system. This process allows the flow of traffic from the context through the physical port that the interface is associated with.

Binding Information. The binding information associates a PDP context to the IP flows of a media. The binding information is generated by the P-CSCF and sent to UE during the IMS session establishment. system receives the binding information from the UE during PDP context activation or modification. The binding information consists of a single authorization token and one or more flow identifiers for the IMS session.

Binding Mechanism. This mechanism is used to associate a PDP context bearer with the IP flow(s) of an IMS session in the PDF.

Binding update. The message that supplies a new binding to an entity that needs to know the new care-of address for a mobile node. The binding update contains the mobile node's home address, new care-of address, and a new registration lifetime.

BLOB. BLock of Bits.

BRA. Binding Revocation Acknowledgement.

BRI. Binding Revocation Indication.

BSC. Base Station Controller. A significant device within the 2G/2.5G RAN, the BSC allocates channels and manages BTS handoff. In 2G wireless, the BSC's upstream interfaces (to the MSC) are always TDM. In 2.5G, a BSC supports both TDM and packet upstream interfaces. In 3G, a BSC can support any combination of TDM and packet, TDM only, or packet only interfaces.

BSS. Base Station Subsystem. The 2G/2.5G Radio Access Network (RAN) technology responsible for connecting the mobile User Equipment (UE) with the Core Network (CN) in a GPRS/UMTS wireless network. The BSS incorporates the BTS, the BSC, and the PCU.

BTS. Base Transceiver Station. A component of the base station, it includes the transmitting and receiving radio equipment. A BTS is sometimes equated with the physical cell site of a wireless network.

Busy Hour. An uninterrupted 60-minute period during which the average volume of traffic is at its maximum.

C

Cached EPS security context. a cached security context to be used in EPS.

CAE. Content Adaptation Engine. An optional component of the Cisco Mobile Video Solution. It runs on the Cisco UCS (Unified Computing System) platform and functions in a UCS cluster to bring video storage and additional video optimization capabilities to the Mobile Video Solution.

Camped on a cell. The MS (ME if there is no SIM) has completed the cell selection/reselection process and has chosen a cell from which it plans to receive all available services. Note that the services may be limited, and that the PLMN may not be aware of the existence of the MS (ME) within the chosen cell.

Care-of address. An IP address at the mobile node's current point of attachment to the Internet, when the mobile node is not attached to the home network. A collocated care-of address is a care-of address assigned to one of the mobile node's network interfaces, instead of one being offered by a foreign agent.

CCA. CC-Answer.

CCP. Compression Configuration Protocol.

CCR. CC-Request>

CLCI Client. DCCA client located in GGSN.

CLCI Server. DCCA server typically located in the Online Charging System.

CDMA. Code Division Multiple Access. One of three wireless technology classes that encompasses 2G, 2.5G, and 3G communications. The other two are GSM and TDMA.

cdmaOne. Defines the 2G and 2.5G versions of CDMA technology. Based on IS-95A and IS-95B standards respectively.

CDMA2000. Defines the 3G version of CDMA technology.

CDR. Charging Data Record. A GTPP-based subscriber accounting record. Charging data record (also known as call detail record) consists of formatted information that includes event-based billing information such as call duration. Different systems generate different types of CDRs. The types, content and handling of CDRs is defined in various 3GPP specs within the TS 32.2xx series,

Cell. The unit of a base station having the ability to radiate in a given geographic area; a “sector” or “face” of a physical radio equipment implementation.

CFE. Common Firmware Environment. The system hardware that contains control processor-based software within the system.

CG. Charging Gateway. The device on the GSM GPRS or UMTS network that collects and maintains Call Detail Records (CDRs) for subscriber PDP contexts. Also referred to as a Charging Gateway function (CGF).

CGF. See CG.

Charging Rule. A set of information including the service data flow filters (IP 5 tuple), the gating status (pass/drop packets matching the rule) and the rating group, for a single service data flow. For an IMS media component a charging rule typically defines a single IP flow associated to a media component (e.g. RTP or RTCP).

CLI. Command Line Interface. A Man-machine Interface (MMI) used to configure, monitor, and administer a network device through its Operating System (OS).

CMIP. Client Mobile IP.

CSFB. Circuit Switched Fallback.

CSG.. Closed Subscriber Group. A Closed Subscriber Group identifies subscribers of an operator who are permitted to access one or more cells of the PLMN but which have restricted access (CSG cells).

CSG Cell. A CSG cell, part of the PLMN, broadcasting a specific CSG identity. A CSG cell is accessible by the members of the closed subscriber group for that CSG identity. All the CSG cells sharing the same CSG identity use the same radio access technology.

CSG ID. A CSG ID is an identifier associated to a cell or group of cells to which access is restricted to a defined group of users.

Current EPS security context. the EPS security context which has been taken into use by the network most recently.

Current serving cell. This is the cell on which the MS is camped.

CO. Central Office. The telecommunications facility where calls are switched.

Context. A specific group of configuration parameters that apply to the ports, interfaces, protocols, and services supported by a system. Each system can support multiple contexts and each context can reside as a separate, logically independent instance. Multiple context support allows numerous like or disparate services to exist on the same physical hardware.

CORBA. Common Object Request Broker Architecture. The Object Management Group's (MAG’s) core specification for distributed object interoperability.

Correspondent node. A node that sends or receives a packet to an MN; the correspondent node may be another mobile node or a non-mobile Internet node.

CP. Control Processor, a high-speed state-of-the-art CPU used by the system.

CSP. Card Slot Port subsystem. This is a software subsystem that manages all cards, slots, and physical ports installed in a system.

D

Data Radio Bearer. Data Radio bearer transports the packets of an E-RAB between a UE and an eNB. There is an one-to-one mapping between the E-RAB and the Data Radio Bearer.

DCCA. DIAMETER Credit Control Application. IETF Diameter Credit Control Application framework.

Dedicated bearer. An EPS bearer that is associated with uplink packet filters in the UE and downlink packet filters in the PDN GW where the filters only match certain packets.

Default APN. A Default APN is defined as the APN which is marked as default in the subscription data and used during the Attach procedure for PDN connection.

Default Bearer. The EPS bearer which is first established for a new PDN connection and remains established throughout the lifetime of the PDN connection.

Dedicated PDP Context. A PDP context with associated TFT filters, this may be a secondary or a primary PDP context (updated after its activation). There can be several such PDP contexts for a UE IP address.

Destination Context. The virtual context, or location, where a particular service configuration resides that mobile subscriber is directed to upon successful authentication through the system.

DHCP. Dynamic Host Configuration Protocol. A protocol by which a host obtains from a server certain information it needs to communicate, such as an IP address, prefix length, and Domain Name System (DNS) server address.

Diameter. A next-generation AAA protocol.

DL. Down link.

DNS. Domain Naming System. A system within the network that maps host-names into IP addresses.

Downlink. The direction of MSC to BSC.

DPCA. Diameter Policy Control Application (PCRF).

DPD. Dead Peer Detection. Also known as Keepalive, this is a timer that starts after the last IKE_AUTH message is sent to the MS and resets when traffic is received from the MS. If no valid messages are received when the timer expires the session is disconnected.

DSCP Marking. DiffServ Code Point (IP Differentiated Services). When the Internet was first deployed many years ago, it lacked the ability to provide Quality of Service guarantees due to limits in router computing power. It therefore ran at a default QoS level, or “best effort”. There were four “Type of Service” bits and three “Precedence” bits provided in each message, but they were ignored. These bits were later re-defined as DiffServ Code Points (DSCP) and are largely honored in peered links on the modern Internet.

Dynamic Charging Rule. Charging rule where some or all of the data within the charging rule (e.g. service data flow filter information) is assigned via real-time analysis using for example dynamic application derived criteria. An example of a dynamic charging rule is a rule determined by the E-PDF by means of real-time SDP derived information analysis.

E

eAN/ePCF. Evolved Access Network/Evolved Packet Control Function.

eHRPD. Evolved High Rate Packet Data (3GPP2).

ePDG. Evolved Packet Data Gateway.

EAP. Extensible Authentication Protocol. EAP is an authentication protocol which provides an infrastructure that enables clients to authenticate with a central authentication server.

EAP-AKA. An extension to the EAP enabling authentication and session key distribution using the UMTS AKA (Authentication and Key Agreement) mechanism.

ECM. EPS Connection Management.

EIR. Equipment Identity Register. This security-based database enables network operators to track mobile phones in a wireless network and to disable stolen equipment.

EHPLMN. Equivalent Home PLMN. Any of the PLMN entries contained in the Equivalent HPLMN list.

EMACS. A standard UNIX text editor. EMACS commands are used to manipulate command lines in the CLI.

EMM. EPS Mobility Manager.

EMM context. An EMM context is established in the UE and the MME when an attach procedure is successfully completed.

EMM-CONNECTED mode. A UE is in EMM-CONNECTED mode when a NAS signalling connection between UE and network is established. The term EMM-CONNECTED mode used in the present document corresponds to the term ECM-CONNECTED state used in 3GPP TS 23.401.

EMM-IDLE mode. A UE is in EMM-IDLE mode when no NAS signalling connection between UE and network exists.

EMS. Element Management System. Defines the system or application used to manage a network device, or groups of like network devices.

Encapsulation. The process of incorporating an original IP packet (less any preceding fields such as a MAC header) inside another IP packet, making the fields within the original IP header temporarily lose their effect.

EPC Network. Evolved packet core network. The successor to the 3GPP Release 7 packet-switched core network, developed by 3GPP within the framework of the 3GPP System Architecture Evolution (SAE).

EPS. Evolved Packet System. The evolved packet system (EPS) or evolved 3GPP packet-switched domain consists of the evolved packet core network and the evolved universal terrestrial radio access network.

Equivalent HPLMN list. To allow provision for multiple HPLMN codes, PLMN codes that are present within this list shall replace the HPLMN code derived from the IMSI for PLMN selection purposes. This list is stored on the USIM and is known as the EHPLMN list. The EHPLMN list may also contain the HPLMN code derived from the IMSI. If the HPLMN code derived from the IMSI is not present in the EHPLMN list then it shall be treated as a Visited PLMN for PLMN selection purposes.

E-RAB identity. The E-RABidentity uniquely identifies an E-RABfor one UE. Note. The E-RAB identity remains unique for the UE even if the UE-associated logical S1-connection is released during periods of user inactivity.

E-RAB. Eveloved Radio Access Bearer. An E-RAB uniquely identifies the concatenation of an S1 Bearer and the corresponding Data Radio Bearer. When an E-RAB exists, there is a one-to-one mapping between this E-RAB and an EPS bearer of the Non Access Stratum.

ESM. EPS Session Management.

ESN. Electronic Serial Number. A unique 32-bit binary number that identifies each cellular device. This information is passed as part of the call setup.

E-UTRAN. Enhanced UTRAN (3GPP).

EV-DO. The second phase of CDMA2000 following 1xRTT deployment. 1xEV-DO stands for 1x Evolution - Data Only, and is characterized by a maximum data rate of 2.4 Mbps.

F

FDMA. Frequency Division Multiple Access. A method of allocating a discrete amount of frequency bandwidth to individual users to allow multiple conversations across many users. The technique of assigning individual frequency slots, and re-use of those slots throughout a system.

FITS. Failure in Time Statistics. A statistical method of determining the number of failures that are expected to occur over a specific time period. The telecommunications industry generally assumes this number to represent the number of failures per million hours (Fpmh).

FEC. Forward Error Correction. The physical link layer may add many extra bits to the data before transmitting it. The receiving physical link layer uses those bits to automatically correct errors in the received data, without needing the data to be retransmitted. The transmitter and receiver must use the same FEC algorithm.

Firewall. A device that protects a private network against intrusion from nodes that are using the public network.

Flow Identifier. An IP flow is indicated uniquely in an IMS session by means of a flow identifier. The flow identifier is created based on the ordinal number of the media stream and of the IP flow in the media where the IP flows are arranged based on the ports used.

FNG. Femto Network Gateway. The FNG enables mobile operators to provide 3G network services to subscribers with wireless handsets via Femtocell Access Points (FAPs). The FNG makes it possible for operators to provide secure access to the operator’s 3G network from a non-secure network, extend wireless service coverage indoors, especially where access would otherwise be limited or unavailable, reduce the load on the macro wireless network, and make use of existing backhaul infrastructure to reduce the cost of carrying wireless calls.

Foreign Agent (FA). A mobility agent on the foreign network that can assist the mobile node in receiving datagrams delivered to the care-of address.

Foreign network. The network to which the mobile node is attached when it is not attached to its home network, and on which the care-of-address is reachable from the rest of the Internet.

Forward Tunnel. The direction of encapsulated data traveling from the Home Agent to the Foreign Agent.

Frequency layer. Set of cells with the same carrier frequency.

FQDN. Fully Qualified Domain Name. An Internet node's FQDN is its complete domain name as defined by the Domain Name System (DNS). A node can be known locally by a relative domain name that is a sub-string of its FQDN, but such a relative name cannot be resolved correctly by Internet nodes outside of the part of the domain name hierarchy indicated by the relative name. The fully qualified name can be resolved from anywhere in the Internet, subject to access control and ability to route of the resolution request.

G

Ga interface. The interface between the GSN (either GGSN or SGSN) and the charging gateway (CG) uses GTPP to communicate.

GBR bearer. Guaranteed Bit Rate Bearer. An EPS bearer that uses dedicated network resources related to a guaranteed bit rate (GBR) value, which are permanently allocated at EPS bearer establishment/ modification.

Gb interface. The interface between the SGSN and the 2G/2.5G RAN base station subsystem - usually the connection with the BSS is to the PCU.

G-CDR. GGSN charging data record.

Gc interface. The interface used by the GGSN to communicate with the Home Location Register (HLR) via a GTP-to-MAP (Mobile Application Part) protocol convertor.

General Purpose PDP Context. A PDP context without associated TFT filters where all the traffic is allowed, including internet traffic. This may be a primary or a secondary PDP context. However, only one PDP context without associated TFT filters can exist.

GERAN. GPRS-Edge Radio Access Network.

Gf interface. The SS7 interface between the SGSN and an EIR.

GGSN. Gateway GPRS Support Node. A device in a GSM GPRS/UMTS data network that performs data session establishment, accounting, and traffic routing.

Gi interface. The interface used by the GGSN to communicate with Packet Data Networks (PDNs) external to the PLMN.

Global Title (GT). A unique SCCP address (such as a mobile phone number) used to identify a destination. A global title does not include routing information.

Global Title Translation (GTT). The SS7 mechanism that provides translation of the destination global titles to enable message routing to the appropriate end-point.

Gn interface. The interface used between two GSN (GGSN and/or SGSN) in the same GPRS/UMTS Public Land Mobile Network (PLMN). This interface serves as both the signalling and data path for establishing and maintaining subscriber PDP contexts.

Go interface. The interface used by the GGSN to communicate with Policy Decision function (PDF) for provisioning of policy for a PDP context bearer used for IMS session media flow transport.

Gp interface. The IP-based interface used between a GGSN and a GPRS support nodes (GSNs, e.g. GGSNs and/or SGSNs) in a different PLMNs.

GPRS. General Packet Radio Service. The GSM version of 2.5G wireless data communications.

GRE. Generic Routing Encapsulation. A generic encapsulation protocols used to tunnel data between various networks. Defined in RFC-2784. This protocol is mandated to be used in R-P and Mobile IP communications.

Gr interface. The SS7 interface between the SGSN and an HLR.

Gs interface. The SS7 interface between the SGSN and an MSC/VLR.

GSM. Global System for Mobile communications. One of three wireless technology classes that encompasses 2G, 2.5G, and 3G communications. The other two are CDMA and TDMA.

GSN. GPRS Support Node can be either an SGSN or a GGSN.

GSS. GTPP Storage Server. An external backup/storage server for one or more types of CDRs: eG-CDRs, G-CDRs, M-CDRs, S-CDRs, and/or SMS CDRs.

GTP. GPRS Tunneling Protocol. The protocol used between the GGSN and the SGSN.

GTP-C. The GPRS Tunneling Protocol (GTP) for the control plane handles signalling between GSNs within the core network.

GTP-P. GTP Prime. The protocol used by the GGSN and SGSN to communicate with the charging gateway.

GTP-U. The GPRS Tunneling Protocol (GTP) for user data plane signalling to handle the user data moving between the RAN and the Core Network (CN) and within the CN.

GT. See Global Title.

GTT. See Global Title Translation.

Gx interface. The interface used by the GGSN to communicate with Charging Rule Function (CRF). Gx interacts between GGSN, the TPF (Traffic Plane Function) and the CRF (Charging Rule Function). It is based on the Diameter base protocol and the Diameter Credit Control Application standard. The GGSN acts as the client where as the CRF contains the Diameter server functionality.

H

Handoff. The process by which an air interface circuit between a mobile node and the network, including all signalling and transfer of user information.

Handover. Procedure that changes the serving cell of a UE in RRC_CONNECTED.

HAT. High Availability Task. This is a software task that manages the operational state of the system.

Home address. The IP address assigned to the mobile node, making it logically appear attached to its home network.

Home Agent (HA). A node on the home network that effectively causes the mobile node to be reachable at its home address even when the mobile node is not attached to its home network.

Home PLMN. This is a PLMN where the MCC and MNC of the PLMN identity match the MCC and MNC of the IMSI.

HLR. Home Location Register. The HLR stores access service parameter information for users belonging to the particular home network.

Home network. The network at which the mobile node seems reachable, to the rest of the Internet, by virtue of its assigned IP address.

HRPD. High Rate Packet Data.

HRPD Access. Combination of the eAN - PCF of the cdma2000 access.

HSGW. HRPD Serving Gateway.

HSS. Home Subscriber Service.

I

IDL. Interface Definition Language. This refers to the application programming interface used to develop CORBA-based management interfaces as defined by the Object Management Group (OMG).

IKE. Internet Key Exchange. An IPSec (Internet Protocol Security) mechanism that is used to create SAs (Security Associations) between two entities in an IP-based VPN (Virtual Private Network).

IMS. IP Multimedia Subsystem. IMS provide a wide application support for transport of voice, video, and data independent of the access support.

IMEI. International Mobile Equipment Identity.

IMEI-SV. International Mobile Equipment Identity - Software Version.

IMSA. IP Multimedia Subsystem Authorization. In case of 3GPP networks this service requires specific support for a roaming IMS subscriber. Apart from other functionality sufficient, uninterrupted, consistent, and seamless user experience is required to particular subscriber session for an application. It is also important that the subscriber gets charged only for the amount of resources consumed by the particular IMS application used.

IMSI. International Mobile Subscriber Identity. Uniquely identifies a subscriber to a mobile telephone service. A 50-bit field, used in GSM system, that identifies a mobile device's home country and carrier.

Interface. As used in context of system services, an interface is a virtual, or logical, assignment of a virtual router instance that provides higher-layer protocol transport. Interfaces are bound to physical ports within the system.

Initial NAS message. A NAS message is considered as an initial NAS message, if this NAS message can trigger the establishment of a NAS signalling connection. For instance, the ATTACH REQUEST message is an initial NAS message.

IP. Internet Protocol. A protocol used for the transmission of packetized data. Part of the TCP/IP suite of communications protocols.

IP-CAN. IP-Capable Access Network.

IP in IP. Refers to the encapsulation of an inner IP header with an outer IP header for tunneling configuration.

IPSec. IP Security. A multi-functional encryption technique used to transport packetized data in an un-readable fashion across multiple network devices.

IPv4v6 capability. Capability of the IP stack associated with a UE to support a dual stack configuration with both an IPv4 address and an IPv6 address allocated.

ISAKMP. Internet Security Association and Key Management Protocol. In IPSec negotiations, this protocol allows the receiver to obtain a public key and authenticate the sender using digital certificates.

ISP. Internet Service Provider. A vendor, or telecommunications carrier, who provides Internet access services to customers.

IuPS. The interface between the Radio Network Controller (RNC) in the UTRAN and a 3G SGSN. Supports both control plane and user data plane signalling, transmitting IP over ATM.

IWF. Inter-working Function. Describes a device that is located between the MSC and the Internet, used to connect wireless subscribers to the Internet through 2G and 2.5G networks.

L

L2TP. Layer 2 Tunneling Protocol. Communications protocol used to establish tunnels between network devices to securely transport data.

LAC. (1) for data tunneling within a VPN environment: L2TP Access Concentrator. A LAC connects an L2TP tunnel from a subscriber to a peer LNS. (2) for mobility management: Location Area Code. Identifies an area in a PLMN within which the MS/UE can move without the need of a location update to the VLR.

LAN. Local Area Network. Used to denote group or groups of physically inter-connected network devices that are capable of sharing information with each other.

Last Visited Registered TAI. A TAI which is contained in the TAI list that the UE registered to the network and which identifies the tracking area last visited by the UE.

Linked Bearer Identity. This identity indicates to which default bearer the additional bearer resource is linked.

LC. Line Card. Rear-installed card within the system that provides physical network connectivity. Most LCs have physical external network interfaces.

LCP. Link Control Protocol.

LMA. Local Mobility Anchor (mobility server, HA-like, P-GW)

LNS. L2TP Network Server. An LNS terminates an L2TP tunnel from a peer LAC and provides a network connection through the tunnel.

Logical Port. A subdivision of a physical port or interface within the system.

LR. Location Registration. An MS which is IMSI attached to non-GPRS services only performs location registration by the Location Updating procedure. A GPRS MS which is IMSI attached to GPRS services or to GPRS and non-GPRS services performs location registration by the Routing Area Update procedure only when in a network of network operation mode I. Both location updating and routing area update procedures are performed independently by the GPRS MS when it is IMSI attached to GPRS and non-GPRS services in a network of network operation mode II or III. An MS which is attached via the E-UTRAN performs location registration by the tracking area update procedure.

LRSN. Local Record Sequence Number. The SGSN or GGSN includes this node-specific, unique sequential number in every partial or complete CDR.

LSA. Localised Service Area. A localised service area consists of a cell or a number of cells. The cells constituting a LSA may not necessarily provide contiguous coverage.

LTE. Long Term Evolution.

M

MAG. Mobile Access Gateway (mobility client, FA-like, HSGW, PMIP S-GW).

Mapped EPS security context. It is a mapped security context to be used in EPS.

MBMS-dedicated cell. cell dedicated to MBMS transmission.

MBR. Maximum Bit Rate (QoS).

M-CDR. Mobility management CDR is generated by an SGSN.

Minimal encapsulation. A variant encapsulation technique specified in RFC 2003 that temporarily alters the structure of the original IP header, but uses fewer bytes for tunneling packets to the care-of-address than the default method (IP-in-IP) uses.

MME. Mobility Management Entity. An EPS element which manages mobility in EPC networks.

MME area. An area containing tracking areas served by an MME.

MME Pool Area. An MME Pool Area is defined as an area within which a UE may be served without need to change the serving MME. An MME Pool Area is served by one or more MMEs ("pool of MMEs") in parallel. MME Pool Areas are a collection of complete Tracking Areas. MME Pool Areas may overlap each other.

Mobile IP. A protocol used to provide IP mobility to IPv4-based nodes, defined in RFC-2002).

MNSRID. Mobile Node Session Reference ID. Denotes the calling number of the MN (i.e. the number that the call is being made from).

Mobile Node (MN). An MN is any device, handset, personal digital assistant, laptop, that connects to the Internet using wireless technology. A node that, as part of normal use, changes its point of attachment to the Internet. Also referred to as Mobile Station (MS).

Mobile Station (MS). See Mobile Node.

Mobility. The ability of a mobile node to change its point-of-attachment from one link to another while maintaining all existing communications and using only its IP home address.

Mobility Agent. A node (typically, a router) that offers support services to mobile nodes. A mobility agent can be either a Home Agent (HA) or a Foreign Agent (FA).

MSC. Mobile Switching Center. The MSC switches MS-originated or MS-terminated traffic. An MSC is usually connected to at least one base station. It may connect to other public networks PSTN, ISDN, etc., other MSCs in the same network. Another name used to identify the MSC is the Mobile Telephone Switching Office (MTSO). The MSC provides the interface for user traffic between the wireless network and other public switched networks, or other MSCs.

MSID. Mobile Station Identification. The Mobile Station ID is the number used to identify a specific mobile device.

MSK. Master Session Key.

MTBF. Mean Time Between Failure. Synonymous with MTTF, this is the anticipated time between failures of the same component.

MTTF. Mean Time To Failure. The average interval of time that a component will operate before failing.

MTTR. Mean Time To Repair. The average amount of time needed to repair or replace a component, recover a system, or otherwise restore service after a failure.

MVG. Mobile Video Gateway. The central component of the Cisco Mobile Video Solution. It employs a number of video optimization techniques that enable mobile operators to enhance the video experience for their subscribers while optimizing the performance of video content transmission over the mobile network.

N

NAI. Network Address Identifier. Used to create a new unique subscriber identifier, based on ESN or other identifiers, when a subscriber enters the network without a user name.

NAS. Network Access Signaling (network attach, authentication, bearer setup, and mobility management).

NAS signalling connection recovery. It is a mechanism initiated by the NAS to restore the NAS signalling connection on indication of "RRC connection failure" by the lower layers.

NAS signalling connection. It is a peer to peer S1 mode connection between UE and MME. A NAS signaling connection consists of the concatenation of an RRC connection via the "LTE-Uu" interface and an S1AP connection via the S1 interface. The UE considers the NAS signalling connection established when the RRC connection has been established successfully. The UE considers the NAS signalling connection released when the RRC connection has been released.

Network Type. The network type associated with HPLMN or a PLMN on the PLMN selector. The MS uses this information to determine what type of radio carrier to search for when attempting to select a specific PLMN. A PLMN may support more than one network type.

NAS protocols. Non-access stratum protocols. The protocols between UE and MSC or SGSN that are not terminated in the UTRAN, and the protocols between UE and MME that are not terminated in the E-UTRAN.

NAT. Network Address Translation. Protocol defined in RFC-1631. Enables a LAN to use one set of IP addresses for an internal traffic and another set of IP addresses for an external traffic.

NEBS. Network Equipment Building Standards. A rigid and extensive set of performance, quality, safety, electrical, and environmental recommendations that are applicable to devices installed in a carrier's Central Office (CO).

NMS. Network Management System. Applications that provide overall management of all network elements. Defined by the third tier of the TMN model of telecommunications management networks.

Nomadicity. The full range of network technology being designed to come to the assistance of the mobile (or nomadic) computer user, not limited to network-layer protocols.

Non-GBR bearer. An EPS bearer that uses network resources that are not related to a Guaranteed Bit Rate (GBR) value.

NPU. Network Processor Unit. A high-speed state-of-the-art processor customized for packet forwarding functions. See Also NPU Manager.

NPU Manager. The NPU manager task provides NPU-related information to other software tasks and performs recovery services for the NPU. An NPU manager task is started for each processing card in the system.

O

OMG. Object Management Group. The OMG is an open membership, not-for-profit consortium that produces and maintains computer industry specifications for CORBA and other related protocols.

OSS. Operations Support System. Methods and procedures that support the daily operations of a carrier's network infrastructure. This includes order processing, equipment assignment, and other administrative functions related to the devices installed in the network.

OOB. Out-of-band Management. Out-of-band management is a method wherein management information exchanged between the network element and its associated management application is carried on a separate communications path from the user data that is coming to/from the network element. Conversely, in-band management is management data that is carried across the same interface as user data.

P

PBA. Proxy Binding Acknowledgement.

PBU. Proxy Binding Update (defined in RFC 5213 Proxy Mobile IPv6).

PCCM. PDN Connection Configuration Message.

PCF. Packet Control Function. A part of the 3G networking equipment that relays packet data and control signalling between the BSC and the PCF. In some cases, the PCF may be integrated into the BSC.

PCO. Protocol Configuration Options.

PCRF. Policy and Charging Rules Function.

P-CSCF. Proxy-CSCF is the first point of contact for the UE in the IMS network. The UE needs to establish a bearer context using which the IMS signalling is carried by the UE with the P-CSCF.

P-CSCF Discovery. As part of the initial context establishment, the system may be required to select/discover a P-CSCF to be used by the UE and send the selected P-CSCF information to the UE in the create response for that PDP context. This procedure is called the P-CSCF discovery procedure.

PCU. Packet Control Unit. Typically a component in the BSS that connects to the BSC to an SGSN in the core network of a GPRS/UMTS wireless network. Once the call is established, the PCU handles the packet data portion of a wireless call.

PDIF. Packet Data Interworking Function. A security gateway providing secure voice and data over a WiFi network via an IPSec tunnel.

PDN. Packet Data Network. Any packet-based data network, such as the Internet or an intranet, that a mobile subscriber would attempt to access.

PDN address. an IP address assigned to the UE by the Packet Data Network Gateway (PDN GW).

PDN Connection. The association between a UE represented by one IPv4 address and/or one IPv6 prefix/address, and a PDN represented by an APN.

PDN-ID. PDN Identifier.

PDP Session. unique association of a subscriber with a network access service given by the combination of MSISDN, APN and IP address. A PDP session can consist of one or more PDP contexts (one primary and zero or more secondary).

PDSN. Packet Data Serving Node. The PDSN is a part of the 3G network that performs packet processing and re-direction to the mobile user's home network through communications with the Home Agent (HA).

PEP. Performance Enhancing Proxy. PEP is used to improve the performance of the Internet protocols (e.g., TCP) on network paths where native performance suffers due to characteristics of a link or sub-network on the path.

P-GW. PDN Gateway.

Pi Interface. The packet data interface from the Foreign Agent to Internet or Home Agent.

Plain NAS message. A NAS message with a header including neither a message authentication code nor a sequence number.

PLMN. Public Land Mobile Network. A term used to designate a GSM, GPRS or UMTS public mobile communications network

PMIPv6. Proxy Mobile IP version 6.

Point Code (PC). A unique address for a node in an SS7 environment.

Policy Decision. The set of policy information AGW receives from E-PDF in a Gx/Ty Diameter message. E-PDF constructs policy decision on the basis of Application Function events and events received over Gx/Ty interface.

Policy Information. The set of policy related data stored in E-PDF associated to a user, including information determined via real-time analysis of an SDP offer/answer exchange derived information in the context of an IMS session, information derived from a pre configured charging rule and preconcerted rule set. These information includes at least charging rules, media component data, binding information and authorized QoS. Policy information such as charging rules and authorized QoS are sent in a policy decision by the E-PDF to the AGW for enforcement.

Pool-area. A pool area is an area within which a MS may roam without need to change the serving CN node. A pool area is served by one or more CN nodes in parallel. All the cells controlled by a RNC or BSC belong to the same one (or more) pool area(s).

Port. A defined physical or logical connection where data enters or leaves a network device.

POS. Packet over SONET.

Preconcerted Charging Rule. Charging rule created and configured in E-PDF by the operator.

PPP. Point-to-Point Protocol. A protocol defined by RFC-1661 that allows for IP connectivity between network devices.

Primary PDP Context. The first PDP context activated by a UE. At the primary PDP context activation an IP address (the PDP address) is assigned to a UE. When activated a primary PDP context is general purpose (i.e. with no associated TFT filters), during its lifetime may change to dedicated (i.e. with associated TFT filters).

PTI. Procedure Transaction Identity. An identity which is dynamically allocated by the UE for the UE requested ESM procedures. The procedure transaction identity is released when the procedure is completed.

PSC. Packet Services Card. The PSC is an application card providing memory and processing capabilities for handling subscriber sessions.

Pull Model. A communication model where a policy decision is requested by the AGW.

Push Model. A communication model where a policy decision is sent unsolicited by the authorizing entity (i.e. E-PDF) to the AGW.

Q

QCI. QoS Class Index.

QoS. Quality of Service. A measure of the service quality provided to a subscriber. In the IP environment, this relates to acceptable levels of quality including bandwidth guarantees, latency, packet ordering, and other service-related levels of service.

R

RA. Router Advertisement.

RADIUS. Remote Authentication Dial In User Service. A group of protocols used to provide AAA functionality for users through a defined server.

RAN or RN. Radio Access Network or Radio Network. The culmination of BTS's and BSC's, including the PCF in 3G networks.

RAT. Radio Access Technologies/Radio Access Type.

RAT-related TMSI. When the UE is camping on an E-UTRAN cell, the RAT-related TMSI is the GUTI; when it is camping on a GERAN or UTRAN cell, the RAT-related TMSI is the P-TMSI.

Rating Group. Information that identifies a user plane data traffic category and is used by the online and offline charging systems for rating purposes.

RCC. Redundancy Crossbar Card. Interface card within the system that provides redundant connectivity for LCs upon a processing card failure.

RCT. Recovery Control Task. A system software task that controls the automatic failover and restart of other tasks within the system. Each recovery action is directed to the RCT from the HAT.

Reverse Tunnel. The direction of encapsulate data traveling from the Foreign Agent to the Home Agent.

Registration Area. A registration area is an area in which mobile stations may roam without a need to perform location registration. The registration area corresponds to location area (LA) for performing location updating procedure, to routing area for performing the GPRS attach or routing area update procedures, and to list oftracking areas (TAs) for performing the EPS attach or tracking area update procedure. The PLMN to which a cell belongs (PLMN identity) is given in the system information transmitted on the BCCH (MCC + MNC part of LAI). In a shared network a cell belongs to all PLMNs given in the system information transmitted on the BCCH.

Registration. This is the process of camping on a cell of the PLMN and doing any necessary LRs.

RFC. Request for Comments. A document that contains Internet standards and protocols, along with other useful information that has relevance to the Internet community. RFCs provide developers the rules and directions on how to implement various Internet communications functions so that they adhere with, are interoperable to, other vendors' implementations of the same function. RFCs are controlled by the International Engineering Task Force (IETF).

Redirection. A message that is intended to cause a change in the routing behavior of the node receiving it.

Registration. The process by which the mobile node informs the home agent about its current care-of address .

Remote redirection. A redirect sent from a source not present on the local network. The source can be located anywhere in the global Internet and may have malicious intent and be untraceable.

Replay attacks. A security violation whereby a malicious entity attempts to imitate a transaction recorded during a previous and valid transaction between two protocol entities. Both protocol entities have to be aware that the subsequent identical traffic streams may no longer be valid. Since the previous transaction was valid, the algorithms for detecting replay attacks need to incorporate data that can never be reproduced in any correct subsequent transaction.

RM. Resource Management subsystem. This group of software tasks assigns resources to other tasks within the system as they are initiated and monitors all resource allocations.

RMU. Rack Mounting Unit. A unit of measurement used in telecommunications to denote the amount of vertical space required to place a network device into an equipment cabinet or telecommunications rack. Each RMU is equivalent to 1.75 in. (4.45 cm.) in height.

RNC. Radio Network Controller.

ROHC. RObust Header Compression.

Route optimization. A process that enables the delivery of packets directly to the care-of address from a correspondent node without having to detour through the home network.

R-P. The interface that exists between the PCF and the PDSN in a CDMA2000 network.

RPLMN. Registered PLMN. This is the PLMN on which certain LR outcomes have occurred (see table 1). In a shared network the RPLMN is the PLMN defined by the PLMN identity of the CN operator that has accepted the LR.

R-P VPN. A routing domain for the ingress R-P protocol consisting of a group of physical or logical interfaces with an associated configuration. The system supports multiple R-P VPNs, and does not forward packets between multiple routing domains.

RS. Router Solicitation.

RSVP. Resource ReSerVation Protocol.

Rule Base. A collection of static charging rules configured in system.

Rule Base ID. The identifier of a rule base.

S

S1. An interface between an eNB and an EPC, providing an interconnection point between the E-UTRAN and the EPC. It is also considered as a reference point.

S101 mode. This mode applies to a system that operates with a functional division that is in accordance with the use of an S101 interface.

S12 Interface. A GTP-U direct tunnel interface/reference point between an S-GW and an RNC.

S13 Interface. A GTP-C/U interface/reference point between an MME and an EIR.

S1-MME. An interface/reference point for the control plane protocol between E-UTRAN and MME.

S3 Interface. An interface/reference point between an MME and a release 8 SGSN.

S4 Interface. An interface/reference point between an S-GW and a release 8 SGSN.

S5/S8 Interface. A PMIPv6/GTP interface/reference point between a P-GW and an S-GW. S5 is the non-roaming (home network) interface between a home P-GW and a home S-GW. S8 is the roaming interface between a home P-GW and a visited S-GW.

SAE. System Architecture Evolution.

SAAU. Simultaneously Attached and Active Users.

SBLP. Service-based Local Policy. This term refers to the instantiation of a policy for use of bearer resources in the access network based on Authorization by a service. In the context of Go interface this is the combined QoS given to a set of IP flows for an IMS session.

SCCP. Signaling Connection Control Part. An SS7 transport layer, connection-oriented protocol that works with MTP-3 to provide routing.

SCCP Network. A proprietary concept designed to facilitate the creation and management of SCCP parameters specific to the SGSN routing.

S-CDR. SGSN generated CDR.

SCT. Shared Configuration Task. This task provides the system’s software with facilities to configure system parameters, retrieve information, and notify the system of configuration changes.

SCTP. Stream Control Transmission Protocol.

SDF. Service Data Flow (specified by 3GPP).

SDT. Signalling De-Multiplexing Task. See Also A11 Manager.

Secondary PDP Context. A new activated PDP context reusing the PDP address and other PDP context information from an already active PDP context, but with a different QoS profile. A secondary PDP context may be dedicated (i.e. with associated TFT filters) or general purpose (i.e. with no associated TFT filters).

SectorID. Sector Address Identifier. This identifier is used to identify an HRPD AN. The Network operator shall set the value of the SectorID according to the rules specified

Selected PLMN. This is the PLMN that has been selected according to subclause 3.1, either manually or automatically.

Service Based Authorization. This term refers to the authorization for use of bearer resources in the access network based on a determination by the application, possibly due to negotiation involving the user. In general, bearer resources may be authorized if the resources requested at the bearer do not exceed the resources negotiated or requested at the service level.

Serving GW Service Area. A Serving GW Service Area is defined as an area within which a UE may be served without need to change the Serving GW. A Serving GW Service Area is served by one or more Serving GWs in parallel. Serving GW Service Areas are a collection of complete Tracking Areas. Serving GW Service Areas may overlap each other.

Session Manager. A group of tasks used by the system for subscriber processing services. Each CP can have multiple session managers. Each session manager is paired with an AAA manager, and can support multiple A11 managers.

SGs Interface. An interface between an MME and an MSC/VLR. Used for Circuit Switched Fallback scenarios.

SGSN. Serving GPRS Support Node. The SGSN tracks the location of mobile devices in a GSM GPRS or UMTS network and routes packet traffic from the BSS to the GGSN.

S-GW. Serving Gateway.

Shared Network. An MS considers a cell to be part of a shared network, when multiple PLMN identities are received on the BCCH.

SID. System Identification. A number that uniquely identifies a network within a cellular of PCS system.

Simple IP. The most commonly used routing protocol on the Internet. This is the IP portion of the TCP/IP suite of protocols used in wireless packet communications.

SIT. System Initiation Task. This critical task is responsible for starting all tasks and system initialization.

SMC. System Management Card, used with the Packet Services Card (PSC) in the ASR 5000 hardware platform. It serves as the primary controller and is responsible for initializing the entire system and loading the software’s configuration image into other cards in the chassis as applicable. Provides out-of-band management interfaces and access to centralized chassis resources.

SMS. Short Message Service.

SoLSA exclusive access. Cells on which normal camping is allowed only for MS with Localised Service Area (LSA) subscription.

Source Base Station. The BS that is in control of the call is designated the source BS and remains the source BS until it is removed from control of the call.

Source Context. The context that a mobile subscribers is placed into by the system when they connect to the system through a PCF.

Source routing. A routing technique that causes some or all intermediate routing points to be represented directly in the data packet to be forwarded. This is in contrast to the typical situation in which intermediate routers rely on acquired routing state information to forward incoming packets.

SPIO. Switch Processor I/O card. Interface card within the system that provides input/output and management interfaces for its corresponding management card.

SS7 Routing Domain. A proprietary concept designed to facilitate the creation and management of SS7-based configuration parameters (e.g., link ids and application server processes) by organizing and grouping them.

Static Charging Rule. Charging rule where all the data within the charging rule (e.g. service data flow filter information) is statically assigned by configuration. Static charging rule are typically configured in system.

STM. SONET Timing Module. Provides Stratum 3 timing for both TDM and packet interfaces.

T

TAI. Tracking Area Identifier. A tracking area that consists of multiple eNBs.

TAI list. A list of TAIs that identify the tracking areas that the UE can enter without performing a tracking area updating procedure. The TAIs in a TAI list assigned by an MME to a UE pertain to the same MME area.

TDM. Time Division Multiplex. A technique for simultaneously transmitting a number of separate data signals over a single communications medium by interleaving a part of each signal one after another.

TDMA. Time Division Multiple Access. One of the wireless technology classes that encompasses 2G, 2.5G, and 3G communications. The other is CDMA.

TFT. Traffic Flow Template.

TIA. Tunnel Inner Address. An IP address assigned by a PDIF/FA and used to create the initial CHILD_SA. After authentication and the creation of a new IPSec_SA with the HoA, the initial CHILD_SA is torn down and the address returned to the pool.

TLLI. Temporary Logical Link Identifier. This Id is derived from the P-TMSI and the RA to uniquely identify an MS in a GPRS sub-network.

TLV. Type Length Value.

Traffic Category. User plane data traffic subject to the same access cost and rating type. A traffic category is identified by a Rating-Group and gathers a set of services.

Traffic flow aggregate. A temporary aggregate of packet filters that are included in a UE requested bearer resource modification procedure and that is inserted into a traffic flow template (TFT) for an EPS bearer context by the network once the UE requested bearer resource modification procedure is completed.

Triangular routing. The path followed by a packet from a correspondent host to a mobile node that must first be routed to the mobile node's Home Agent (HA).

Tunnel. A path followed by a first packet while it is encapsulated within the payload portion of a second packet.

Tunneling. The same as encapsulation, but with additional connotations about changing the effects of Internet routing on the original IP packet.

U

UE. User Equipment. Term commonly used in 3G/4G scenarios. Equivalent to MS or mobile station (commonly used in 2G/2.5G scenarios) and to MN or mobile node (commonly used in 2G/2.5G scenarios involving IP-level functions).

UE-associated logical S1-connection. The UE-associated logical S1-connection uses the identities MME UE S1AP ID and eNB UE S1AP ID. For a received UE associated S1-AP message the MME identifies the associated UE based on the MME UE S1AP ID IE and the eNB identifies the associated UE based on the eNB UE S1AP ID IE. The UE-associated logical S1-connection may exist before the S1 UE context is setup in eNB.

UE-associated signalling. When S1-AP messages associated to one UE uses the UE-associated logical S1-connection for association of the message to the UE in eNB and EPC.

UMTS. Universal Mobile Telecommunications System. The GSM-based evolution for 3G wireless communications. This term is also referred to as W-CDMA.

Unicast/MBMS-mixed cell. This is the cell supporting both unicast and MBMS transmissions

Uplink. Any BS that supports the call other than the source BS is designated as a target BS.

UTRAN. UMTS Terrestrial Radio Access Network.

V

Visited PLMN. This is a PLMN different from the HPLMN (if the EHPLMN list is not present or is empty) or different from an EHPLMN (if the EHPLMN list is present).

VLR. Visited Location Register. The VLR caches access service parameter information (such as the MS/UE’s mobile number) that it obtains from a particular user's HLR upon call establishment.

VoIP. Voice over IP. The protocol that describes the packetization of analog voice signals into digital data packets.

VPN. Virtual Private Network. A virtual router or domain instance that enables secure communications between allowed network users and devices. Context is the work most commonly used to denote this type of connectivity.

VSNP. Vendor Specific Network Protocol.

VSNCP. Vendor Specific Network Control Protocol.

W

WCDMA or W-CDMA. Wideband CDMA. The GSM-based evolution for 3G wireless communications. This term is also referred to as UMTS.

X

X2 Interface. It 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.