Glossary of terms
| 1PPS | One Pulse Per Second |
AAI-48 | 48-bit Administratively Assigned Identifier |
AAI-64 | 64-bit Administratively Assigned Identifier |
ACK | Acknowledgement |
ADEV | Allan deviation |
AP | (Wireless LAN) Access Point |
ARB | Arbitrary |
ARTC | Arbitrary Reference Time Clock |
AV | Audio/Video |
AVB | Audio/Video Bridging |
| BBU | Base Band Unit (upper-layer processing within a basestation; equivalent to the CPRI term REC) |
BC | Boundary Clock (see T-BC) |
BITS | Building Integrated Timing Source |
BMC | Best Master Clock |
BMCA | Best Master Clock Algorithm |
BPSK | Binary Phase Shift Keying |
| BTS | Base Transceiver Station (the basestation name for a 2G network, e.g. GSM) |
CAN | Controller Area Network |
CDMA | Code Division Multiple Access |
CES | Circuit Emulation Service |
CID | Company ID |
CMI | Coded Mark Inversion |
CMLDS | Common Mean Link Delay Service |
CP | Communication Profile (according to IEC 61784-1:200710) |
CPF | Communication Profile Family (according to IEC 61784-1:2007) |
CPRI | Common Public Radio Interface (a specification for radio over fibre produced by the CPRI consortium, www.cpri.info) |
| CRAN | Centralised Radio Access Network (sometimes used to refer to Cloud RAN, although this is more general concept than Centralised RAN) |
CSMA/CD | Carrier Sense Multiple Access with Collision Detection |
CSN | Coordinated Shared Network |
CTC | Channel Time Clock |
cTE | constant Time Error |
| CU | Centralised Unit (higher-layer processing within the basestation) |
DAN | Dual Attached Node |
DANH | Dual Attached Node with HSR protocol |
DSL | Digital Subscriber Line |
DSLAM | Digital Subscriber Line Access Multiplexer |
dTE | dynamic Time Error |
| DU | Distributed Unit (lower-layer processing within the basestation) |
E2E | End-to-End |
EC | Equipment Clock |
| eCPRI | enhanced Common Public Radio Interface (a specification for radio over a packet network, e.g. Ethernet or IP, produced by the CPRI consortium, www.cpri.info) |
EEC | Ethernet Equipment Clock |
EEC | synchronous Ethernet Equipment Clock |
| eEEC | enhanced Ethernet Equipment Clock (the enhanced SyncE clock defined in G.8262.1) |
ELI-48 | 48-bit Extended Local Identifier |
ELI-64 | 64-bit Extended Local Identifier |
| eNodeB | evolved NodeB (basestation name for a 4G network, e.g. LTE) |
| EPC | Evolved Packet Core (the core network in 4G) |
EPON | IEEE 802.3 Ethernet passive optical network (as specified in IEEE Std 802.3-2008) |
| ePRC | enhanced Primary Reference Clock (defined in G.811.1) |
| ePRTC | enhanced Primary Reference Time Clock (defined in G.8272.1) |
| eRE | Radio Equipment (eCPRI term for the physical-layer processing within the basestation; equivalent to the RRU or RRH) |
| eREC | Radio Equipment Controller (eCPRI term for the higher-layer processing within the basestation; equivalent to the combination of a CU and DU) |
ESMC | Ethernet Synchronization Messaging Channel |
ESS | Extended Service Set |
ETH | Ethernet MAC layer network |
ETY | Ethernet PHY layer network |
EUI-48 | 48-bit Extended Unique Identifier |
EUI-64 | 64-bit Extended Unique Identifier |
FCS | Frame Check Sequence |
FDD | Frequency Division Duplexing |
FFM | Flicker Frequency Modulation |
FFO | Fractional Frequency Offset |
FM | Frequency Modulation |
FPC | Floor Packet Count |
FPM | Flicker Phase Modulation |
FPP | Floor Packet Percent |
FPR | Floor Packet Rate |
FTM | Fine Timing Measurement |
ITU-T G.9960 and ITU-T G.9961 | |
GBAS | Ground Based Augmentation System |
GbE | Gigabit Ethernet |
GM | Grandmaster (see T-GM) |
GMT | Greenwich Mean Time |
| gNodeB | The basestation name for a 5G network |
GNSS | Global Navigation Satellite System (generic name for the various satellite-based navigation and time distribution services, e.g. GPS, GLONASS, Beidou etc) |
GPON | Gigabit-capable Passive Optical Network |
GPS | Global Positioning System |
gPTP | generalized Precision Time Protocol (see PTP) |
HRM | Hypothetical Reference Model |
HRPD | High Rate Packet Data |
IANA | Internet Assigned Numbers Authority |
ICV | Integrity Check Value |
HSR | High availability Seamless Redundancy |
IP | Internet Protocol |
IPv4,6 | IPv6 Internet Protocol version 4 / 6 |
IRNSS | Indian Regional Navigation Satellite System |
IS | Integration Service |
ISO | International Organization for Standardization |
ISS | Internal Sublayer Service |
IWF | Inter-Working Function |
JD | Julian Date |
JDN | Julian Day Number |
LAN | Local Area Network |
LCI | Location Configuration Information |
LLC | Logical Link Control |
LTE | Long Term Evolution |
LTE-A | Long Term Evolution – Advanced |
M2M | Machine to Machine |
MAC | Media Access Control (according to IEEE Std 802.3-2005) |
MACsec | Media Access Control security |
MAFE | Maximum Average Frequency Error |
MA-L | MAC Addresses Large |
MA-M | MAC Addresses Medium |
MAN | Metropolitan Area Network |
MA-S | MAC Addresses Small |
MATIE | Maximum Average Time Interval Error |
max|TE| | Maximum absolute Time Error |
MBMS | Multimedia Broadcast Multicast Service |
MBSFN | MBMS based on Single Frequency Network |
MD | Media-Dependent |
MDEV | Modified Allan Deviation |
MII | Media-Independent Interface |
| MIMO | Multiple Input Multiple Output |
MJD | Modified Julian Day |
MLME | MAC Layer Management Entity (IEEE 802.11) |
MPCP | MultiPoint Control Protocol (IEEE 802.3) |
MPDPDU | MPCP Data Unit (IEEE 802.3) |
MTIE | Maximum Time Interval Error |
NE | Network Element |
NIST | National Institute of Standards and Technology (see www.nist.gov) |
| NodeB | The basestation name for a 3G network, e.g. UMTS |
NRZ | Non-Return to Zero |
NTP | Network Time Protocol |
NUI-48 | 48-bit Network Unique Identifier |
NUI-64 | 64-bit Network Unique Identifier |
OAM | Operations, Administration and Maintenance |
OC | Ordinary Clock |
OFD | Observed Floor Delay |
OLT | Optical Line Terminal (IEEE 802.3) |
ONT | Optical Network Terminal |
ONU | Optical Network Unit (IEEE 802.3) |
OSC | Optical Supervisory Channel |
OSSP | Organization-Specific Slow Protocol |
OTN | Optical Transport Network |
OUI | Organizational Unique Identifier (allocated by the IEEE) |
P2P | Peer-to-Peer |
PAM | Pulse Amplitude Modulation |
PDV | Packet Delay Variation |
PEC | Packet-based Equipment Clock |
PDU | Protocol Data Unit |
PEC-S | Packet-based Equipment Clock Slave |
PHY | Physical layer (according to IEEE Std 802.3-2005) |
PICS | Protocol Implementation Conformance Statement |
PLL | Phase-Locked Loop |
PM | Phase Modulation |
PNT-F | Packet Network Timing Function |
PP | Packet Processing |
ppm | parts per million |
PPS | Pulse Per Second |
PRC | Primary Reference Clock |
PRTC | Primary Reference Time Clock (defined in G.8272) |
PSN | Packet Switched Network |
PTP | Precision Time Protocol (defined in IEEE1588) |
PRP | Parallel Redundancy Protocol |
QZSS | Quasi-Zenith Satellite System |
RE | Radio Equipment (CPRI term for the physical-layer processing within the basestation; equivalent to the RRU or RRH) |
REC | Radio Equipment Controller (CPRI term for the upper-layer processing within the basestation; equivalent to the BBU) |
RF | Radio Frequency |
| RRH | Remote Radio Head (physical layer processing within a basestation; another name for the RRU; equivalent to the CPRI term RE) |
| RRU | Remote Radio Unit (physical layer processing within a basestation; another name for the RRH; equivalent to the CPRI term RE) |
RT-DSLAM | Remote Terminal-Digital Subscriber Line Access Multiplexer |
RTT | Radio Transmission Technology |
RTT | Round-Trip Time |
RWFM | Random Walk Frequency Modulation |
SA | Security Associations |
SAI-48 | 48-bit Standard Assigned Identifier |
SAI-64 | 64-bit Standard Assigned Identifier |
SBAS | Satellite Based Augmentation System |
SDH | Synchronous Digital Hierarchy |
SEC | SDH Equipment Clock |
SFD | Start Frame Delimiter |
SM | State Machine |
SNTP | Simple Network Time Protocol |
SOF | Start of Frame |
SSM | Synchronization Status Message |
SSMB | Synchronization Status Message Byte |
SSU | Synchronization Supply Unit |
STA | Station |
STM | Synchronous Transport Module |
STM-N | Synchronous Transport Module-N |
SyncE | Synchronous Ethernet |
TAI | Temps Atomique International (international atomic time) |
T-BC | Telecom Boundary Clock (defined in G.8273.2) |
TC | Traffic Class |
TC | Transparent Clock (see T-TC) |
TDD | Time Division Duplexing |
TDEV | Time Deviation |
TDM | Time Division Multiplexing |
TDMA | Time Division Multiple Access |
TD-SCDMA | Time Domain Synchronized CDMA |
TE | Time Error |
TG | Task Group |
T-GM | Telecom Grandmaster (defined in G.8273.1) |
TIE | Time Interval Error |
TLV | Type, Length, Value (according to IEEE Std 802.1AB) |
ToD | Time of Day |
ToS | Type of Service |
TS | TimeStamp |
T-TC | Telecom Transparent Clock (defined in G.8273.3) |
T-TSC | Telecom Time Slave Clock (defined in G.8273.2) |
UCMM | UnConnect Message Manager |
UCT | UnConditional Transfer |
UDP | User Datagram Protocol |
UDP/IP | User Datagram Protocol (see IETF RFC 768 B5) / Internet Protocol |
UI | Unit Interval |
UTC | Coordinated Universal Time |
UTC | Universal Time Co-ordinated |
UTRA | Universal Terrestrial Radio Access |
VCO | Voltage Controlled Oscillator |
VLAN | Virtual Local Area Network |
WCDMA | Wideband CDMA |
WDM | Wavelength Division Multiplexing |
WFM | White Frequency Modulation |
WG | Working Group |
WiMAX | Worldwide Interoperability for Microwave Access |
WLAN | Wireless Local Area Network |
xDSL | x-type Digital Subscriber Line |
xPON | x Passive Optical Network |
Relationship between fronthaul terms
BTS | 2G term for a basestation | ||
|---|---|---|---|
Node B | 3G term for a basestation | ||
eNodeB | 4G term for a basestation | ||
Generic terms | CPRI terms | ||
BBU | REC | Upper layer processing (i.e. not physical layer) within a basestation | |
RRU, RRH | RE | Physical layer processing (i.e. radio layer) within a basestation | |
gNodeB | 5G term for a basestation | ||
Generic terms | eCPRI terms | ||
CU | eREC | Higher-layer processing within a basestation | |
DU | Lower-layer processing within a basestation | ||
RRU, RRH | eRE | Physical layer processing (i.e. radio layer) within a basestation | |
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