List of VOLTE Abbreviations

1×RTT Single carrier radio transmission technology
3GPP Third generation partnership project
3GPP2 Third generation partnership project 2
AAA Authentication, authorization and accounting
AAL ATM adaptation layer
AAR AA request
ACA Accounting answer
ACK Acknowledgement
ACR Accounting request
AGCF Access gateway control function
A-GNSS Assisted global navigation satellite system
AGW Access gateway
AKA Authentication and key agreement
ALG Application level gateway
AMR Adaptive multi-rate
AMR-WB Adaptive multi-rate wideband
AOC Advice of charge
AP Authentication proxy
APN Access point name
APN-AMBR Access point name–aggregate maximum bit rate
ARP Allocation and retention priority
AS Application server
ASA Abort session answer
ASR Abort session request
ATCF Access transfer control function
ATGW Access transfer gateway
ATM Asynchronous transfer mode
AUC Authentication centre
AUID Application usage identification
AUTN Authentication token

AVC Advanced video coding
AVP Attribute value pair; audio visual profile
AVPF Audio visual profile with feedback
B2BUA Back to back user agent
BGCF Breakout gateway control function
BICC Bearer independent call control
BS Billing system
BSC Base station controller
BSS Base station system
BTS Base transceiver station
CAT Customized alerting tone
CB Communication barring
CCBS Completion of communications to busy subscriber
CCF Charging collection function
CCNR Completion of communications on no reply
CD Communication deflection
CDF Charging data function
CDMA Code division multiple access
CDR Charging data record
CLI Calling line identification
CN Core network
CSFB Circuit switched fallback
DCH Dedicated traffic channel
PCH Paging channel
CFB Communication forwarding busy
CFNL Communication forwarding on not logged in
CFNR Communication forwarding no reply
CFNRc Communication diversion on mobile subscriber not
reachable
CFU Communication forwarding unconditional
CGF Charging gateway function
CGI Cell global identification
CK Ciphering key
CLIP Calling line identification presentation
C-MSISDN Correlation mobile subscriber international ISDN
number
CONF Conference calling
CPC Continuous packet connectivity
CPE Customer premise equipment
CRS Customized ringing signal
CS Circuit switched
CSCF Call session control function
CSFB Circuit switched fallback
CSMO Circuit switched mobile originating
CTF Charging trigger function
Data over cable service interface specification
DPCCH Dedicated physical control channel
DPDCH Dedicated physical data channel
DRB Data radio bearer
DRX Discontinuous reception
DTAP Direct transfer application part
DTM Dual transfer mode
DTMF Dual-tone Multi-frequency
DTX Discontinuous transmission
EATF Emergency access transfer function
ECF Event charging function
ECM Evolved packet system connection management
E-CSCF Emergency CSCF
ECT Explicit communication transfer
E-DCH Enhanced dedicated channel
EDGE Enhanced data rates for global evolution
EFR Enhanced full rate
eHRPD Evolved high rate packet data
EMM Evolved packet system mobility management
eMSS Enhanced mobile switching centre server
eNB Evolved nodeB
eNodeB Evolved nodeB
EPC Evolved packet core
ePDG Evolved packet data gateway
EPS Evolved packet system
E-SMLC Evolved serving mobile location centre
E-STN-SR Emergency session transfer number for SRVCC
ETSI European Telecommunications Standards Institute
E-UTRAN Evolved universal mobile telecommunications
system terrestrial radio access network
EV-DO Evolution data only
FA Flexible alerting
FGI Feature group indicator
FoR Follow on request
FTP File transfer protocol
GAA Generic authentication architecture
GBR Guaranteed bit rate
GERAN Global system for mobile communications/EDGE
radio access network

GGSN Gateway general packet radio service
support node
GMLC Gateway mobile location centre
GPRS General packet radio service
GPS Global positioning system
GRUU Globally routable user agent URI
GSM Global system for mobile communications
GSMA GSM association
GTP GPRS tunnelling protocol
GTP-C GPRS tunnelling protocol control plane
GTP-U GPRS tunnelling protocol user plane
GWF Gateway function
HARQ Hybrid automatic repeat request
HLR Home location register
HOLD Communication hold
HPLMN Home public land mobile network
HRPD High rate packet data
HSDPA High speed downlink packet access
HS-DSCH High speed downlink shared channel
HSGW HRPD serving gateway
HSPA High speed packet access
HSS Home subscriber server
HSUPA High speed uplink packet access
HTTP Hyper text transfer protocol
IAM Initial address message
IBCF Interconnection border control function
ICID Internet protocol multimedia subsystem charging
identifier
ICS Internet protocol multimedia subsystem centralised
services
I-CSCF Interrogating CSCF
ICSI Internet protocol multimedia subsystem
communication service identification
IETF Internet engineering task force
iFC Initial filter criteria
IK Integrity key
IM Instant messaging
IMEI International mobile equipment identity
IMPI IMS private user identity
IMPU Internet protocol multimedia subsystem public user
identity
IMS Internet protocol multimedia subsystem
IMSI International mobile subscriber identifier
IMS-MGW IMS media gateway
IM-SSF Internet protocol multimedia service switching
function