martin clark
telecommunications consulting
Telecom Glossary
telecommunications consulting
Telecom Glossary
physical layer
Layer 1 of the open systems interconnection (OSI) model. The physical layer protocol is the hardware and software in the line terminating device which converts the databits needed by the datalink layer into the electrical pulses, tones or other form.aA A A A A A+S A-law A/D A= AA AAA AAA AAI AAL AAL-IE AAL1 AAL2 AAL3/4 AAL5 AAR AARP ABM ABNF ABOR ABR ABR AC AC AC ac ACAP ACB ACCT ACD ACE ACF ACF ACFC ACI ACK ACL ACR ACSE AD ad adaptive differential pulse code modulation (ADPCM ADC ADDMD ADM ADMD administrator ADPCM ADS ADSL ADSL (asymmetric digital subscriber line) ADSP adspec advanced peer to peer networking (APPN) AE ae AEP aero AES AF af AFI AFP AFT ag agent AgentX AH AHIP ai AII AIM AIS AL AL al ALG ALLO am AM AM AMI amplification amplitude amplitude modulation (AM) AMPS AMR AMR-WB AMS AMSIX AN AN an ANA analogue transmission ANI ANS ANSI anycast ao AO AOI AOL AOW AP AP AP APDU APEX API APL RR APNIC APOP APP APPC APPE APPL application application layer APPN APS aq AR ar ARC ARCFOUR ARCNET ARE AREQUIPA ARIN ARL ARP ARPA arpa ARPANET ARPANET ARQ ARR ARR ARS ARS AS as AS (autonomous system) ASBR ASC ASCII ASCII (American standard code for information inte ASE ASIC ASK ASM ASN.1 ASO ASP asynchronous data transfer asynchronous transfer mode (ATM) at AT&T ATCP ATE ATM ATM-LE ATMARP ATME ATMM AtmMIB ATMP ATO ATP ATS attenuation attenuation distortion AU au AuC audio circuits AUG AUI AUTH AUU AVI AVI AVMMS AVP aw AW AWG Awnd AYT az
bB B B B B-BC B-channel B-ICI B-ISDN B-ISDN (broadband integrated services digital netw B-ISUP B-NT B-NT1 B-NT2 B-SP B-STP B-TA B-TE B-TE1 B-TE2 B8ZS ba BA BABT BACP BAKOM balanced balanced transmission Balun bandwidth BAP BAPT BAS baseband BASize BAT BB bb BBN Bc BCC BCC bcc BCD BCDBS BCN BCOB BCP BCP BCP (best current practice) BCS bd BDAT BDR Be be bearer service BECN BEDC BEEP BEL BER BER BER (bit error rate) BERT bf BFTP bg BGMP BGP BGP-ASC bh bi BID binary code BIND BIP BIS BIS BIS BISSI Bisync bit/s bitrate or bit speed BIU biz bj BLER block bm BML BMPT bn BN BNC BNF BNN BNS bo BOC BOM BOOTP BOP BPDU BPON BPP BPSK BR br BRA BRI BRI (basic rate interface) bridge BRK BRL broadband broadcast brouter Brouter BS BS bs BSC BSC BSD BSI BSN BSS BSS BSSID BT bt Btag BTAM BTC BTS BTx BUS busy hour busy hour traffic bv BVCP BVPS bw by BYE byte bz
cC C C C C C C C-4 C-bit C-channel C-n c-plane C/I C/R C= CA ca CAC CAC CAD CAD-CAM CAI CALS CALSCH CAN CAP CAPA CAPI CAPI CARP carrier frequency carrier sense multiple access with collision detec CAS CAS CASE CAST CAT Cat.5 Cat.5 Cat.6 Cat.6 Cat.7 Cat.7 CATNIP CBC CBCP CBDS CBO CBR CBT cc CC cc CCA CCA CCD CCD CCIR CCIS CCITT CCP CCR CCS CCS CCSO ccTLDs CCU CCW cd CD CD CDDI CDLC CDMA CDN CDS CDUP CDV CDVT CE CE CE CEC CEI cell CellB CELP CELP (code excited linear predication) CEN CEP CEPT CEQ CER CES CES cf CF CFCCH CFDP CFI CGI ch chaddr CHAP CHARGEN CHPID ci CI CI ciaddr CIC CICS CID CID CIDR CIFS CIM CIM CIP CIPX CIR circuit transfer mode circuit-switching ck cl CL Clav CLEC CLI CLI CLI client CLIP CLIR Clk CLLM CLNAP CLNES CLNP CLNS CLP CLR CLS CLSF CLTP CLTS CLU cm CM CME CME CMI CMIP CMIP (common management information protocol) CMIS CMISE CMOL CMOT CMR CMS CMS CMT CN cn CNAME CNLS CNRP CO CO co CO&M coaxial cable COBS CODEC codec (coder/decoder) COH COI COLT COM com CON Conf configuration management connection admission control connection-oriented connectionless CONS console console port control plane COOKIE coop COP COPS COPS COPS-PR CORBA COS COSS COTS CP CP CPBCCH CPCCCH CPCS CPE CPE (customer premises equipment) CPL CPS CPU cq CR cr CR CR CRC CRC (cyclic redundancy check) CRF CRL CRLF CRM CRMA crosstalk CRS CRS Crypto API CS CS CS-CELP CS7 CS8 CSCH CSMA CSMA/CD CSR CSRC CSU Ctag CTD CTP CTS CTS CTS CTS cu CU CUG CV cv CWD Cwnd cx CX cy cz
dD D D-bit D-channel DA Daemon DAL DAMA DAP DAP DARPA DAS DAS DAS Das DASD DASS DAT data data compression datagram datalink layer DAYTIME dB DB-25 DB-37 DB-9 DBPSK DC DC DC-bit DCC DCCS DCD DCE DCE DCE (data circuit-terminating equipment) DCF DCF DCL DCLASS DCN DCS DD DDCMP DDDB DDI DDI DDL DDP DDS DE DE de DEA DEBUG DEC DEC DECNET DEFLATE DEL DELE DES DESE DESEbis DFI DGP DGPT DGT DGT DHC DHCP DIB DICOM DICT DID DIF DiffServ DIS DISC DISCARD DISP DIT DIX DIXIE dj dk DL DLCI DLE DLS DLSw DlswMIB DLU DLUR DLUS DM DM dm DM DM DMA DMD DME DMI DMO DMTF DMZ DN DN DNA DNCP DNIC Dns DNS DNS NCACHE DNS (domain name system) DNS RR DNS SRV DNS UPDATE DNSSEC DNS_ALG DOCSIS DoD DODIIS DOM domain name DOP DOS DOS dot12 DPC DPCM DPI DPS DPSK DQDB DQPSK DR DRS DS DS DS DS DS DS Field DS-PHY DS0 DS1 DS2 DS3 DSA DSAP DSCP DSE DSE DSG DSL DSLAM DSLCP DSML DSN DSN DSP DSP DSP DSR DSS DSS DSS1 DSS2 DSSS DSU DTD DTE DTE (data terminal equipment) DTMF DTP DTP DTR DU DUA DUAL duplex (full duplex) DUT DV DVMRP DVP DWDM DXC DXI dz
eE E E-bit E-R E.164 E1 E2 E3 EA EA-bit EAB EAP EAPOL EBCDIC EBCDIC EBCN EBGP EBN ebusiness EC EC ec EC ECC ECC echo ECHO ECHOCTL ECHOE ECHOK ECHOKE ECHONL ECMA ECML ECN ECP ECS ECSA ECSD ED ED EDC EDGE EDI EDI (electronic data interchange) EDIFACT EDNS0 edu ee EF EFCI EFCN EFI EFI EFM EFS EFS (error free seconds) EFTPOS eg EGA EGP EGPRS EGRP eh EHLO EIA EIGRP EIN EIR EIR EL EL EL EL-bit ELAN ELAP ELLC EM EM email email EMC EMC (electromagnetic compatibility) EMI EMI (electromagnetic interference) EML EMSD EN EN Enb ENCAP ENCAPS encapsulation encryption ENQ EntityMIB ENUM EOF EOL EOM EOR EOT EP EPOS EPRT EPSV EQ ER er ERA Erlang ERM ERP es ES ES ES-IS ESC ESCON ESD ESI ESMTP ESP ESRO ESS ESSID et ETACS ETAG Etag ETB ETFTP ETHERIP EtherMIB ethernet LAN ETR ETS ETSI ETX ETX/ACK EU EUI EXP EXPN extranet
ff F f F F F-bit FAC fading FADU FANP FAS fault management FAX FC FCAPS FCC FCS FDD FDDI FDDI (fibre distributed data interface) FDMA FDR FDX FE FEAC FEBE FEC FEC FECN female connector FEP FERF FEXT FF FF FG FH FH-PHY FI fi FIB FID FIFO file transfer FILO FIN FIN FINGER FIPS firewall FITL fj fk flow control FlowMIB FLP FM fm FM FMBS FMH fo FOIRL FOOBAR forwarding FP FPE FQDN fr FR FRAD FRAD (frame relay access device) frame frame frame relay framing FRBS frequency modulation (FM) FRFH FRMR FRR FRS FRSE FRTE FS FS FSBS FSK FSK (frequency shift keying) FSS FTAM FTN FTP FTPSRV FTTB FTTC FTTH FTTK FUNI FYI FZA
gG.703 G.704 G.732 GA ga GAP GARP gateway GB Gbit/s GBSVC GCAC GCRA gd GDMO ge GECOS gf GFC GFSK gg gg GGP GGSN gh GI gi giaddr GIF GII GKMP gl GLOP gm GME GMII GMPLS GMRP GMSK GMT gn GND gopher GOS GOS (grade of service) GOSIP gov gp GPRS GPRS (general packet radio service) gr GRE GS gs GSM GSM (global system for mobilecommunication) GSMP GSN GSS_API GSTN gt GTF gu GUI GUI (graphical user interface) GVRP gw gy gzip
hH H-FP H.261 H0 H11 H12 half duplex Hamming code HAP Hayes protocol HCI HCS HDB3 HDLC HDLC (high level data link control) HDP HDR Hdr HDSL HDSL (high bitrate digital subscriber line) HDX header HEC HELO HELP HEMP HEMS hexadecimal HFC HIPERLAN HIPPI hk HLF HLI hm HMAC HMP hn HOB HOPOPT Host host Host-Host HP HPR hr HS HSRP HSSI HT ht HTCP HTML html (hypertext markup language) HTTP http (hypertext transfer protocol) HTTPS hu hub huffman code HUP HW hyperlink
iI I I-bit i-frame I.420 I/G I/O IA2 IA5 IAB IANA IANA (Internet assigned numbers authority) IANAifType IAP IAPP IASG IBGP IBM IBSS IC iCalendar ICANON ICCN ICD ICF ICI ICIP ICLS ICMP ICMPv6 ICP ICP ICP ICPC ICRNL ICRP ICRQ ICS ICV id ID IDEA Ident IDI IDL IDMIB IDMR IDN IDP IDPR IDR IDRP IDU IDUP IE ie IE IEC IEC IEE IEEE IEEE 802 IEEE 802.2 IEEE 802.2 IEEE 802.3 IEEE 802.3 IEEE 802.5 IEEE 802.5 IEN IESG IETF IETF (Internet engineering task force) IEXTEN IFG IfMIB IGM IGMP IGNCR IGNPAR IGP IGRP IHL IISP IKE il ILEC ILL ILL ILM ILMI ILMI im IMAC IMAP IMAXBEL iMIP IMP IMP IMP IMP/host IMPP IMSI IMSSI IN in INAP InARP IND info INI INLCR INN INPCK int INT INTELSAT interface interference Internet InterNIC intranet IntSrv INX io IOC IOCP IOP IOS IOTP IP IP IP IP (Internet protocol) IP address IP address IP address class IP Comp IP Mobility IP Paging IP Precedence IP-E IP-MTU IPComp IPCP IPHC IPI IPL IpMIB IPMS Ipng IPO IPOA IPP IPPM IPS IPsec IPv4 IPv4 IPv4 (Internet protocol version 4) IPv6 IPv6 IPv6 (Internet protocol version 6) IPv6 routers IPv6-ADDR IPv6-AUTH IPv6-CP IPv6-DISC IPv6-ESP IPv6-Frag IPv6-ICMP IPv6-NoNxt IPv6-Opts IPv6-Route IPv6-SA IPX IPXCP IPXWAN iq IQUERY IR ir IR-PHY IRA IRC irc IRDP IRN IRP IRP IRS IRTF IRTP is IS IS IS-IS ISAKMP iSCSI ISDN ISDN (integrated services digital network) ISDU ISI ISI ISIG ISM ISN ISO ISO (International Organization for Standardizatio ISO 2110 ISO-10646 ISO-10646- J-1 ISO-IP ISOC ISP ISP ISP ISP ISP (Internet service provider) ISPBX ISR ISSI ISSN ISTRIP ISUP it IT IT ITC iTIP ITOT ITT ITU ITU (International Telecommunications Union) ITU-R ITU-T ITU-T (ITU Standardization sector) ITU-T recommendation IUCLC IUT IVD IW IWF IWP IWU IX IXANY IXC IXOFF IXON
lL L-bit L2F L2TP L2TP-FR LA la LA LAC LAN LAN (local area network) LANE LANG LAP LAPB LAPD LAPM LASER LATA latency layered protocol lb lc LCGN LCN LCP LCT LD LD LD-CELP LDAP LDAP API LDDB LDIF LDP LDP LDP LDP LDUP LE LE LE LEC LEC LED LEN Level 0 LF LF LFA LFA LFC LFSID LGN LH LH LI LI li LIB LIC LIFO line code LINX LIPKEY LIST Listserv LIVT lk LLA LLAP LLC LLC LLC (logical link control) LLI LMCS LMDRP LMDS LME LMI LMTP LN LNA LNS LOC LOF LOP LPD LPDU LPR LQC lr ls LSA LSAck LSB LSD LSNAT LSP LSP LSR LSR LSRR LSU LSUB lt LT LTE LTH LTU LU lu LUNI lv LW LX ly LZS LZS-DCP LZW
mM M M-ACTION M-bit M-bit M-CANCEL-GET M-CREATE M-DELETE M-EVENT-REPORT M-GET m-plane M-SET M1-interface M2-interface M3-interface M4-interface M5-interface MA ma MAC MAC (medium access control) MAC address MADCAP MAE MAIL male connector MAN MAN (metropolitan area network) managed object management plane manager Manchester code MANET MAP MAP MAPOS MARC mark MARS MASC MAU MAU MaxCR MaXIM-11 MB Mb/s Mbit/s MBONE MBP Mbps MBS MBZ mc MC-bit MCDV MCF MCGAM MCI MCLR MCNS MCP MCP MCR MCS MCS MCTD MCU MD MD md MD MD2 MD4 MD5 MDI MDL MdmMIB MDN MDP MDU media medium Megaco MEMS message handling system (MHS) message switching messaging service MF MF MF MF mg MGCP mh MH MHRP MHS MHTML MIB MIB MIB (management information base) mib-2 MIB-II MIC MICP MID MID midcom MIF MII mil MIL-STD MIM MIME MipMIB MIS MIS MISTY1 MIXER mk MKD ml ML MLDP MLID MLP MLT MLTNET mm MM MM mm MMF MMI MMS mn MNP MNT MO mo mobile IP MOCS MODE modem modem modulation monomode fibre MOs MOSPF MOTIS MP mp MP MP+ MP3 MPEG MPEG (motion pictures experts group) MPH MPLS MPLS (multiprotocol label switching) MPLS-ATM MPLS-BGP MPLS-FR MPLS-SHIM MPLS-VPN MPOA MPOFR MPP MPP MPPC MPPE MPT mq mr MRRU MRU MS MS MS ms MS-bit MSAP MSB MSC MSDP MSDTP MSDU MSF msg MSL MSN MSN MSN MSOH MSP MSP MSP MSS MSS MST MSVC mt MTA Mta MTAE MTBF MTL MTP MTP MTP MTP MTS MTTR MTU MTU MTU mu Mu-law MUA MUF Multicast multimedia service multimode fibre multiplexing multipoint multiprotocol museum MUX mv MVI MVL MVS mw mx my mz MZAP
nN N(R) N(S) N-ISDN N/A N/P-bit NA na NAE NAI NAK name Name/Finger NAPTR NARP NAS NASA NAT NAT-PT NAU NAV NBFCP NBMA NBNS NBP NBS nc NCOP NCP NCP NCP NCP NCS NDF NDIS NDS ne NE NECP NEF NEL NEM net NET netascii NetBEUI NetBIOS NETBLT NETCRT NETRIS NETRJS NETRJT network layer network performance (NP) network-node interface (NNI) NewsML NEXT nf NFB NFILE NFS ng NGL NHC NHFLE NHRP ni NIC NIC NICNAME NIS NIST NIU NL nl NLA NLA NLM NLPID NLRI NLST nm NM NMB NMC NMF NMF NML NMS NMS (network management system) NN NN NNI NNTP no NOC NOFLSH noise NOOP NOP np NP NPA NPC NPDU NPMA NPSI nr NREN NRM NRT NRZ NRZI NSAP NSDU NSF NSF NSFnet NSN NSP NSR NSS NSS NSSA NT NT1 NT2 NTBBA NTE NTN NTP NTU nu NUI NUL NULL encryption NULL service NVFS NVP NVT NVT-ASCII NWG nz
oO O-bit O-bit O-bit O/R OAF OAKLEY OAM OAM&P OAMC OC OC-1 OC-12 OC-192 OC-3 OC-48 OC-n OCC OCCN OCD OCRNL OCRP OCRQ OCS OCSP ODA ODETTE ODI ODMR ODP ODP official standards OFN OfTel OH OID OLCUC OLRT OLS OLTU om OM OMAP OMC OMG ONC ONLCR ONLRET ONOCR ONP OO OOF OOK OPAL OPC opcode OpenPGP OPOST optical fibre ORB org ORS OS OSF OSF OSH OSI OSI (open systems interconnection) OSI model OSIE OSINLCP OSIRM OSPF OSPF (open shortest path first) OSS OTA OTAPA OTASP OUI OWF
pP P P P P-bit P/F P1-interface P3-interface PA pa PABX PAC PAC PACCH packet packet assembler/disassembler (PAD) packet transfer mode packet-switching PAD PAD PADI PADO PADR PADS PADT PAF PAM PAMA PANS PAP parallel data transmission PARC PARENB PARMRK PARODD PAS PASS PASTE PASV Path PathErr PathTear PBX PC PC PCCP PCF PCI PCI PCIM PCM PCM (pulse code modulation) PCMAIL PCN PCR PCS PCS PDA PDCH PDF PDH PDN PDO PDTCH PDU PDU PE pe peer partner peering PENDIN performance management PF pf PF-KEY PFC PFR pg PG PGL PGM PGP PGP PH ph PH Ph-SAP phase shift keying (PSK) PHB PHY physical layer PICS PID PIM PIM-DM PIM-SM PIM-SSM PiMF PIN PIN PING PingMIB PINT PIPE PIU pixel PIXIT pk PKCS PKI pl PL PL PL-LE PL-OAM PL-OU PLCP plesiochronous digital hierarchy (PDH) PLK PLL PLMTS PLP PLS PLS PLU PLW pm PM PM PMA PMD PMP PMTU PMUX pn PNA PNG PNNI PNS POH POI POI PolSK PON POP POP POP port PORT POS POS POSIX post office POTS PP PPD PPDU PPM PPP PPP (point-to-point protocol) PPP multilink PPP-LINK PPP/AAL5 PPP/FR PPP/HDLC PPPoE PPPoISDN PPPoSONET PPPoX.25 PPS PPTP pr PRA PRBS PRDMD presentation layer presentation medium PRI PRI (primary rate interface) PRIM primary multiplex (PMUX) PrintMIB PRM PRMA PRMD PRNG protocol protocol stack ProtocolID proxy Proxy-PAR PRR PRS PRT Prty ps PSAP PSDN PSE PSF PSH PSI PSK PSN PSN PSTN PT pt PTCCH PTE PTI PTM PTO PTP PTR PTS PTT pty PU PV PVC PVC PVCC PVPC pw PW PWD PWM py
qQ Q-SIG Q3 QA QA QA qa QAF QAF QAM QAM (quadrature amplitude modulation) QCLASS qdu QNAME QOS QOS QPSK QPSX QTYPE quality of service (QOS) QUIT QUOTE Qx
rR R R R R reference point R-bit R-bit RA RA RAC RADIUS RAI RAM RAP RARP RAS RAS RATP RBB RBOC RC RC RC2 RC4 RC5 RCA RCN RCPT RCR Rcwd RD RD RDA RDBMS RDI RdmsMIB RDN RDP RE re real-time application reconnection Ref regenerator REIN REJ repeater REQ RES RESP REST Resv REsvConf ResvErr ResvTear RETR REX RF RFC RFC (request for comments) RFI RFP RFQ RFS RFS RG RI RI RI RID RID RIF RII RIP RIP (routing information protocol) RIPE RIPng RISC RJ-11 connector RJ-45 connector RJE RJOR RL RLC rlogin RLP RM RM RM RMCP RMD RMON RMON (remote monitoring) RMT RNFR RNR RNTO ro RO RO ROA ROHC ROM RORE ROSE routed router router alert routing protocol routing table RP RPC RPOA RPR RPS RPS RPSL RPSL RQ RR RR RR RR RRE RRP RRQ RRR RRT RS RS RS RS Rs RS RS-232 RS-422 RS-449 RSA RSA RSE RSET Rsh RSOH Rsp RSRVD RSS RST RSU RSVD RSVP Rsvp RT RT RTA RTCP RTFM RTO RTP RTP RTR RTS RTS RTSE RTSP RTT RTTVAR ru RU RUC RUIP rw RW Rwhois RWP Rx RxD RXJ RXR RZ
sS S&F s-bit S-bit S-bit s-frame S/Key S/MIME S/T SA SA sa SAA SAA SAAL SAB SABM SABME SACK SAD samba SAML SAML SAP SAP SAP SAPI SAR SAR SAS SAS SASL SAT SAT SATA SATF sb SB SB SBM SBS SBSVC sc SC SC sca SCCCN SCCRP SCCRQ SCE scj scn SCR SCR scr SCSI SCSP SCTP sd SD SDCP SDDI SDE SDES SDF SDH SDH (synchronous digital hierarchy) SDL SDL SDLC SDLC (synchronous datalink control) SDP SDR SDRP SDT SDTP SDU SDXF se SE SE SECB SECBR SECSH SecureFast SecurID security management SEC_GSS segment SEGV SEL ser serial data transmission SERIAL_ server SES session session layer SFD SFT sg SGML SGMP SGSN sh SHA SHDSL SHTTP si SI siaddr Sieve SIFT SIG SIIT SIM simplex SIP SIP SIPP SIR SITA SITE sj sk SKIP SKIPJACK SKMP sl SLA SLA SLE SLI SLIP SLP SLP SM SM SM sm SM SM SM SMAE SMASE SMB SMDS SME SMF SMF SMF SMFS SMI SMK SML SMNT SMON SMP SMS SMT SMTP SMX SN sn SN SNA SNA (systems network architecture) SNACP sname SNAP SNAP SNI SNI SNMP (simple network management protocol) SNMP extensions snmpMIB SNMPv1 SNMPv2 SNMPv3 SNMPv3-v2-v1 SNP SNPA SNPP SNQP SNTP SO so SOAP SOC socket socket SOCKS SOH SOH SOIF SOML SONET SONET (synchronous optical network) SP SP SP SPAM SPC SPD SPE SPED SPF SPI SPID SPIRIT SPIRITS SPKI SPKM SPL SPM SPN SPNA SPPI SPT SPX SQL sr SR SR SRB SRE SREJ SRF SRI SRL SRP SRT srTCM SRTS SRTT SS SS SS7 SSAP SSCF SSCOP SSCP SSCS SSH SSH-ARCH SSH-CONNECT ssh-connection SSH-TRANS ssh-userauth SSH-USERAUTH SSI SSL SSM SSM SSRC SSRR SSTHRESH ST ST ST ST st ST2+ sta STACK STAT STAT statistical multiplexing STD STD (standard) STD1 STDA STDL STE STE STE STM STM STM STM-1 STM-16 STM-4 STM-64 STM-n StopCCN STOR storage medium STOU STP STP STP STP (shielded twisted pair) str STRU STS STS-1 STS-12 STS-192 STS-3 STS-48 STS-n STX SUB subnetting SUPDUP SUT sv SVC SVC SVI SVL SVP SVP switch SWS SX sy SYN synchronisation synchronous data transfer Syslog SYST sz
tT T T T-bit T-bit T-bit T-bit T1 T3 TA TA TACACS Tag-switching TAPI TAR TAT TAT TB TB TBF Tc tc TC TC TC TCA TCAM TCAP TCE TCF TCN TCP TCP (transmission control protocol) TCP extensions TCP/IP TCP/IP TcpMIB td TDD TDM TDMA TE TE TE telecommunications management network (TMN) TELNET TERM tf TFA TFTP TG tg th TH THT TIB TIC TIFF TIG TIM TIME time division multiplex (TDM) TIP TIPS tj tk TKEY RR TLA TLA TLAP tld TLD tlf TLI Tlr TLS tls tlu TLV tm TMN TMux tn TN3270E TNS TNVIP to TO TOA token ring LAN TOP TOS TOSTOP TP TP tp TP TP TP TP TP1 TP2 TP3 TP4 TPE TPI TPID TPM TPON TR TR tr TR TR transaction transport layer TRCC TRIP trTCM trunk TS TS TS16 TSB TSF TSI TSIG TSO TSOPT TSP tspec TSSI TSTP TSWTCM TT tt TTC TTL TTP TTR TTRT TTY TTY_OP_ ISPEED TTY_OP_END TTY_OP_OSPEED TU TU-n TUBA TUG TUID tunneling TURN tv tv tw twisted pairs Tx TxD tz
uU U-bit u-frame U-interface u-plane U/L UA ua UA UAE UAL UAL UAP UART UAS UB UBR UCLA UCS UCSB UDDI UDF UDLR UDP UDP (user datagram protocol) UdpMIB UDT UFT ug UI UIDL UIDPLUS uk um UME UMTS UMTS (universal mobile telephone service) UNARP unbalanced transmission UNI unicode Unicode uniq UNIX UNRP UPC UPF UPS UpsMIB UPT URA URG URI URL URL (uniform resource locator) URN us US US USA usage parameter control (UPC) USART USB USENET USER user plane user-network interface (UNI) USERS USF USM USR1 USR2 UT UTC UTF UTOPIA UTP UTP (unshielded twisted pair) UUCP UUCP UULP UUP UUS uy uz
vV V V V+D V.10 V.11 V.24 V.32 V.34 V.35 V.36 V.90 V1-V2 va VACM valid cell, packet or frame VAN VANS VarBind VAS VASP VAX VBR VBR-NRT VBR-RT VC VC vc VC VC CEPF VC CPF VC-11 VC-12 VC-21 VC-22 VC-31 VC-32 VC-4 VC-n vCard VCC VCCE VCDIFF vcf VCI VCI VCID VCL VDISCARD VDSUSP VDU ve VEMMI VENUS VEOF VEOL VEOL2 ver VERASE VF VF VFIP VFLUSH VFS vg VGA vi VID VINTR virtual connection VISCII VKILL VLAN VLAN VLAN (virtual-bridged LAN) VlanHello VLNEXT VLS VLSM VM VMA VMTP vn VNS VoD VOIP VOIP (voice over IP) VP VP CEPF VP CPF VP-XC VPC VPCE VPI VPI VPIM VPL VPN VPN (virtual private network) VPNI VPNID VPT VQUIT VR VR VRC VREPRINT VRFY VRRP VSTART VSTATUS VSTOP VSUSP VSWTCH VT VT VT VT-100 VT1.5 VT100 VT2.0 VT3.0 VT6.0 VTAM VTE VTOA vu VWERASE
wW/U WAE WAL2 WAN WAP WARC WAVE WCCP WDM WDP WDS web browser web server WEBDAV WEBI WebNFS webpage website WEN WEP WF wf WG WHOIS WINS WLAN WLL WML Worldwide Web (www) WP-TCP WPAD WPKI WRQ WS ws WS WSF WSOPT WSP WSP WTA WTAI WTLS WTP WWW