acronyms.comp revision 1.230
1$NetBSD: acronyms.comp,v 1.230 2019/02/19 13:51:17 sevan Exp $ 23WHS three-way handshake 38VSB 8-state vestigial side band modulation 4AA anti-aliasing 5AAA authentication, authorization, [and] accounting 6AAT average access time 7ABI application binary interface 8ABR available bit rate 9ABRT automatic bug reporting tool 10AC alternating current 11ACI adjacent channel interferer 12ACID atomicity, consistency, isolation, durability 13ACK Amsterdam compiler kit 14ACK acknowledgement 15ACL access control list 16ACL active current loop 17ACL asynchronous connection less 18ACP auxiliary control {process,program} 19ACPI advanced configuration and power interface 20ACS access control set 21ACU automatic calling unit 22ADB Apple desktop bus 23ADC analog [to] digital converter 24ADD acronym driven development 25ADO active data objects 26ADP automatic data processing 27ADPCM adaptive differential pulse code modulation 28ADS alternate data stream 29ADSL asymmetric digital subscriber line 30ADT abstract data type 31AER advanced error reporting 32AES Advanced Encryption Standard 33AFP Apple Filing Protocol 34AFS Andrew File System 35AGC automatic gain control 36AGP accelerated graphics port 37AI analog input 38AI artificial intelligence 39AL access list 40AL active link 41ALE address latch enable 42ALS ambient light sensor 43ALU arithmetic and logical unit 44ALUA asymmetric logical unit access 45AM access method 46AM alignment mask 47AM amplitude modulation 48AMD Advanced Micro Devices Inc 49AMDD Agile model-driven development 50AMI alternate mark inversion 51AMP asymmetric multiprocessing 52AMQP advanced message queuing protocol 53AMT active management technology 54AN Arabic number 55ANR application not responding 56ANSI American National Standards Institute 57AO analog output 58AOL Alert-on-LAN 59AOS add or subtract 60AP access point 61AP application processor 62API application programming interface 63APEI ACPI platform error interface 64APIC advanced programmable interrupt controller 65APIPA automatic private IP addressing 66APM advanced power management 67APM application performance management 68APU accelerated processing unit 69APT advanced persistent threat 70AQM active queue management 71ARAT always running APIC timer 72ARC adaptive replacement cache 73ARC Advanced RISC Computing 74ARC automatic reference counting 75ARM Advanced RISC Machines 76ARP Address Resolution Protocol 77ARPA Advanced Research Projects Agency 78ARQ automatic repeat request 79ARR address range register 80ARU audio response unit 81AS autonomous system 82ASA Adaptive Security Appliance 83ASAN Address Sanitizer 84ASC advanced smart cache 85ASCII American Standard Code for Information Interchange 86ASD agile software development 87ASE advanced software environment 88ASF alert standard format 89ASIC application-specific integrated circuit 90ASK amplitude shift keying 91ASLR address space layout randomization 92ASN autonomous system number 93ASPM active state power management 94ASQ automated software quality 95ASR address space register 96AST abstract syntax tree 97AST asynchronous system trap 98AT access time 99AT advanced technology 100ATA advanced technology attachment 101ATAPI advanced technology attachment packet interface 102ATC address translation cache 103ATM asynchronous transfer mode 104ATX advanced technology extended 105AV anti virus 106AVL Adelson-Velsky-Landis 107AVX advanced vector extensions 108BA byte align 109BAL basic assembly language 110BAR base address register 111BBS bulletin board system 112BCC blind carbon copy 113BCD binary coded decimal 114BCR byte count register 115BCS base configuration space 116BD baud 117BDD binary decision diagram 118BDI bit deinterleave 119BDUF big design up front 120BEDO burst extended data output 121BER basic encoding rules 122BER bit error {rate,ratio} 123BERT boot error record table 124BFD binary {file,format} descriptor 125BFKL big fscking kernel lock 126BFS breadth-first search 127BFT binary file transfer 128BGA ball grid array 129BGP Border Gateway Protocol 130BGPSEC BGP Security 131BIND Berkeley Internet Name Daemon 132BIOS Basic Input/Output System 133BIOS built-in operating system 134BIST built-in self-test 135BIU bus interface unit 136BKDG BIOS and kernel developer's guide 137BLAS basic linear algebra subprograms 138BLC back light control 139BLOB binary large object 140BM bus master 141BMC baseboard management controller 142BMIC bus master interface controller 143BN boundary neutral 144BNF Backus-Naur form 145BO binary output 146BOF beginning of file 147BOM beginning of message 148BOM byte order mark 149BP base pointer 150BP boot processor 151BPB BIOS parameter block 152BPDU bridge protocol data unit 153BPF Berkeley Packet Filter 154BPI bits per inch 155BPM business process modelling 156BPS bits per second 157BPSK binary phase shift keying 158BQS Berkeley quality software 159BRE basic regular expression 160BS backspace 161BS binary sequence 162BSA basic service area 163BSD Berkeley Software Distribution 164BSDP Boot Service Discovery Protocol 165BSF bit scan forward 166BSOD blue screen of death 167BSP binary space partition 168BSP board support package 169BSP bootstrap processor 170BSR bit scan reverse 171BSS basic service set 172BSS block started by symbol 173BSSID basic service set identifier 174BT BitTorrent 175BT Bluetooth 176BT bit test 177BTC bit test [and] complement 178BTR bit test [and] reset 179BTS bit test [and] set 180BTS bug tracking system 181BW bandwidth 182BWM block-write mode 183BUAG big ugly ASCII graphic 184CA certificate authority 185CAD computer-aided design 186CAM computer assisted manufacturing 187CAM conditional access module 188CAM content addressable memory 189CARP Common Address Redundancy Protocol 190CAS column address strobe 191CAS compare and swap 192CAS computer algebra system 193CASE computer aided software engineering 194CAU control access unit 195CAV constant angular velocity 196CBC cipher block chaining 197CBR constant bit rate 198CC carbon copy 199CCD charge coupled device 200CCI co-channel interferer 201CCNUMA cache-coherent non-uniform memory access 202CD cache disable 203CD compact disc 204CDDA compact disc digital audio 205CDMA code division multiple access 206CDP Cisco Discovery Protocol 207CDRAM cache dynamic random access memory 208CER canonical encoding rules 209CF compact flash 210CFB cipher feedback 211CFG context-free grammar 212CFG control-flow graph 213CFI control-flow integrity sanitizer 214CG control gate 215CGA Color Graphics Adapter 216CGI common gateway interface 217CGN Carrier-Grade NAT 218CHAP Challenge-Handshake Authentication Protocol 219CHS cylinder/head/sector 220CI continuous integration 221CI {common,component} interface 222CIDR Classless Inter-Domain Routing 223CIF common intermediate format 224CIFS Common Internet File System 225CIL common intermediate language 226CIR carrier-to-interference ratio 227CIS contact image sensor 228CISC complex instruction set {computer,computing} 229CJK Chinese, Japanese, [and] Korean 230CLF common log format 231CLI command line interface 232CLR common language runtime 233CLTT closed loop thermal throttling 234CLUT color look-up table 235CLV constant linear velocity 236CM configuration management 237CMA concert multithread architecture 238CMC chassis management controller 239CMC corrected machine check 240CMS {configuration,content,course} management system 241CMI control {management,method} interface 242CMOS complementary metal-oxide-semiconductor 243CMP chip multi-processing 244CMS content management system 245CMYK cyan magenta yellow black 246CN {common,canonical} name 247CNC computer numerical control 248CNR carrier-to-noise ratio 249COF current operating frequency 250COFDM coded orthogonal frequency division multiplexing 251COFF common object file format 252COM component object model 253COMA cache-only memory architecture 254CORBA common object request broker architecture 255COS class of service 256COW copy-on-write 257CP continuous pilot 258CPB core performance boost 259CPC central processor complex 260CPC cpu performance counters 261CPE common phase error 262CPE common platform enumeration 263CPER common platform error record 264CPG clock pulse generator 265CPI cycles per instruction 266CPL current privilege level 267CPLD complex programmable logic device 268CPP C preprocessor 269CPS characters per second 270CPT command pass through 271CPU central processing unit 272CR carriage return 273CRC cyclic redundancy check 274CRL carrier recovery loop 275CRLF carriage return line feed 276CRT cathode ray tube 277CRUD create, read, update, and delete 278CS cable select 279CS chip select 280CS code segment 281CS computer science 282CSDL {common,conceptual} schema definition language 283CSI channel state information 284CSI common system interface 285CSMA carrier sense multiple access 286CSMA/CA carrier sense multiple access with collision avoidance 287CSMA/CD carrier sense multiple access with collision detection 288CSR control [and] status registers 289CSRG Computer Systems Research Group 290CSS cascading style sheets 291CSV comma-separated values 292CTM close to metal 293CTR counter [mode] 294CTS clear to send 295CUA common user access 296CUT coordinated universal time 297CV control voltage 298CVE common vulnerabilities and exposures 299CVS Concurrent Versions System 300DA destination address 301DAA distributed application architecture 302DAB digital audio broadcasting 303DAC digital [to] analog converter 304DAC discretionary access control 305DAD duplicate address detection 306DANE DNS-based Authentication of Named Entities 307DAO disk at once 308DAP Directory Access Protocol 309DAT digital audio tape 310DAT dynamic acceleration technology 311DB database 312DBA database administrator 313DBA dynamic bandwidth allocation 314DBB data bus buffer 315DBC design by contract 316DBL dynamic buffer limiting 317DBMS database management system 318DBS database server 319DC direct current 320DCC Direct Client-to-Client 321DCC direct cable connect 322DCD data carrier detect 323DCE data control equipment 324DCE distributed computing environment 325DCIM data center infrastructure management 326DCIM digital camera images 327DCL Digital Command Language 328DCOM distributed component object model 329DCOP Desktop COmmunication Protocol 330DCS data collection systems 331DCT discrete cosine transform 332DCU data cache unit 333DDC display data channel 334DDE dynamic data exchange 335DDK device driver kit 336DDL data description language 337DDR double data rate 338DDS direct digital sound 339DDWG Digital Display Working Group 340DE debugging extensions 341DE desktop environment 342DEA data encryption algorithm 343DEC Digital Equipment Corporation 344DEK data encryption key 345DEP data execution prevention 346DER distinguished encoding rules 347DES Data Encryption Standard 348DF don't fragment 349DFA deterministic finite automaton 350DFC data flow control 351DFS depth first search 352DFS distributed file system 353DFSAN Data Flow Sanitizer 354DFT diagnostic function test 355DFT discrete Fourier transform 356DGL data generation language 357DH Diffie-Hellman 358DHCP Dynamic Host Configuration Protocol 359DIFS distributed inter-frame space 360DIMM dual inline memory module 361DIRT design in real time 362DL diode logic 363DL discrete logarithm 364DL download 365DLE data link escape 366DLL dynamic link library 367DLP discrete logarithm problem 368DMA direct memory access 369DMI desktop management interface 370DMS document management system 371DMT discrete multitone modulation 372DMU data management layer 373DNARD Digital network appliance reference design 374DND drag and drop 375DNLC directory name lookup cache 376DNS Domain Name System 377DNSSEC DNS Security Extensions 378DOE distributed object environment 379DOF data over fibre 380DOM document object model 381DOS denial of service 382DOS disk operating system 383DP DisplayPort 384DPC deferred procedure call 385DPCM differential pulse code modulation 386DPD dead peer detection 387DPI deep packet inspection 388DPI dots per inch 389DPL descriptor privilege level 390DPS Display PostScript 391DPST display power savings technology 392DRAAS disaster recovery as a service 393DRAM dynamic random access memory 394DRBG deterministic random bit generator 395DRI direct rendering infrastructure 396DRM digital rights management 397DRRS display refresh rate switching 398DS debug store 399DSA digital signature algorithm 400DSAP destination service access point 401DSB double-sideband modulation 402DSDT differentiated system descriptor table 403DSL dataset and snapshot layer 404DSL digital subscriber line 405DSL domain specific language 406DSLAM digital subscriber line access multiplexer 407DSN delivery status notification 408DSO dynamic shared object 409DSP digital signal processor 410DSSS direct sequence spread spectrum 411DTD document type definition 412DTE data terminal equipment 413DTE dumb terminal emulator 414DTL diode-transistor logic 415DTLS datagram transport layer security 416DTS digital thermal sensor 417DUT device under test 418DVB digital video broadcasting 419DVCS distributed version control system 420DVD digital versatile disc 421DVFS dynamic voltage and frequency scaling 422DVI device independent 423DVI Digital Visual Interface 424DVR digital video recorder 425E-XER extended XML encoding rules 426EABI embedded-application binary interface 427EAI Email Address Internationalization 428EAI Enterprise Application Integration 429EAP Extensible Authentication Protocol 430EAPOL EAP over Lan 431EBCDIC Extended Binary Coded Decimal Interchange Code 432EBDA Extended BIOS Data Area 433EBR extended boot record 434EC elliptic curve 435ECC elliptic curve cryptography 436ECC error correction code 437ECDH elliptic curve Diffie-Hellman 438ECDL elliptic curve discrete logarithm 439ECDLP elliptic curve discrete logarithm problem 440ECDSA elliptic curve digital signature algorithm 441ECL emitter-coupled logic 442ECN explicit congestion notification 443ECP enhanced capability port 444ECS enhanced chip set 445ECS extended configuration space 446EDAC error detection and correction 447EDAT enhanced dynamic acceleration technology 448EdDSA Edwards curve digital signature algorithm 449EDGE explicit data graph execution 450EDID extended display identification data 451EDO extended data out 452EDS electronical data sheet 453EEE energy efficient ethernet 454EEPROM electrically erasable programmable read only memory 455EFI extensible firmware interface 456EFL emitter follower logic 457EFM eight to fourteen modulation 458EGA Enhanced Graphics Adapter 459EGP exterior gateway protocol 460EH extension header 461EIDE enhanced IDE 462EISA extended industry standard architecture 463EINJ error injection table 464ELF executable and linking format 465ELS entry level system 466EMI electro-magnetic interference 467EMP electro-magnetic pulse 468EMR electro-magnetic radiation 469EMACS Editor MACroS 470EOF end of file 471EOI end of interrupt 472EOIS end of interactive support 473EOL end of life 474EOL end of line 475EOT end of transmission 476EPIC explicitly parallel instruction computing 477EPP enhanced parallel port 478EPRML extended partial response, maximum likelihood 479EPROM erasable programmable read only memory 480ERD emergency recovery disk 481ERD entity relationship diagram 482ERE extended regular expression 483ERST error record serialization table 484ESAN Efficiency Sanitizer 485ESB enterprise service bus 486ESDI enhanced small disk interface 487ESDRAM enhanced synchronous dynamic random access memory 488ESI enclosure services interface 489ESS electronic switching system 490ESS extended service set 491ESSID extended service set identifier 492EST enhanced speedstep 493ETL extract, transform, load 494EU execution unit 495EULA end user license agreement 496FAT file allocation table 497FBRAM frame buffer random access memory 498FCIF full common intermediate format 499FCL fiber channel loop 500FCS frame check sequence 501FDC floppy disk controller 502FDD floppy disk drive 503FDDI fiber distributed data interface 504FDE full disk encryption 505FDT flattened device tree 506FEA finite element analysis 507FEC forward error correction 508FET field-effect transistor 509FF finite field 510FF form feed 511FFDH finite-field Diffie-Hellman 512FFH functional fixed hardware 513FFI foreign function interface 514FFM focus follows mouse 515FFS Fast File System 516FFS find first set 517FFT fast Fourier transform 518FG floating gate 519FHSS frequency hop spread spectrum 520FID frequency identifier 521FIFO first in, first out 522FILO first in, last out 523FIPS Federal Information Processing Standards 524FIR fast infrared 525FLOPS floating [point] operations per second 526FLOSS free/libre/open source software 527FM frequency modulation 528FMR false match rate 529FOSS free/open source software 530FPGA field programmable gate array 531FPM fast page mode 532FPR floating point register 533FPU floating point unit 534FQDN fully qualified domain name 535FRR false rejection rate 536FRU field replaceable unit 537FS file system 538FSB front side bus 539FSCK file system check 540FSF Free Software Foundation 541FSK frequency shift keying 542FSM finite-state machine 543FTA fault tree analysis 544FTL flash translation layer 545FTP File Transfer Protocol 546FTPS File Transfer Protocol Secure 547FUS fast user switching 548FWH firmware hub 549FWS folding white space 550GAL generic array logic 551GAS generic address structure 552GC garbage collector 553GCM Galois counter mode 554GCR group-coded recording 555GDI Graphics Device Interface 556GDT global descriptor table 557GEM graphics environment manager 558GEM graphics execution manager 559GENA general event notification architecture 560GHC Glasgow Haskell compiler 561GHES generic hardware error source 562GIC generic interrupt controller 563GID group identifier 564GIF graphics interchange format 565GMCH graphics and memory controller hub 566GNU GNU's Not Unix 567GOP graphics output protocol 568GOT global offset table 569GPE general purpose event 570GPF general protection fault 571GPG GNU Privacy Guard 572GPL [GNU] General Public License 573GPR general purpose register 574GPS generalized processor sharing 575GPT GUID partition table 576GPU graphics processing unit 577GR golden ratio 578GRE generic routing encapsulation 579GSI global system interrupt 580GUI graphical user interface 581GUID globally unique identifier 582GVFS git virtual file system 583HA high availability 584HAL hardware abstraction layer 585HAT hashed array tree 586HATEOAS hypermedia as the engine of application state 587HBA host bus adapter 588HCF halt and catch fire 589HCI host controller interface 590HCI human-computer interaction 591HCL hardware compatibility list 592HDCP High-bandwidth Digital Content Protection 593HDD hard disk drive 594HDL hardware description language 595HDMI High-Definition Multimedia Interface 596HDTV high-definition television 597HECI host embedded controller interface 598HEST hardware error source table 599HF high frequency 600HFM highest frequency mode 601HID human interface device 602HKP HTTP Keyserver Protocol 603HLL high-level language 604HMA high memory area 605HMI human-machine interface 606HOOD hierarchical object oriented design 607HP Hewlett-Packard 608HPC high performance computing 609HPET high precision event timer 610HSM hardware security module 611HSM hierarchical storage management 612HT hyper-threading 613HTC hardware thermal control 614HTCC high temperature co-fired ceramic 615HTML HyperText Markup Language 616HTT hyper-threading technology 617HTTP Hypertext Transfer Protocol 618HTTPS Hypertext Transfer Protocol Secure 619HVM hardware virtual machine 620HVDS High-Voltage Differential Signaling 621HWASAN Hardware-assisted Address Sanitizer 622HZ Hertz 623I2O intelligent input/output 624IA information assurance 625IAAS infrastructure as a service 626IANA Internet Assigned Numbers Authority 627IBC iterated block cipher 628IBM International Business Machines 629IBS instruction based sampling 630IBSS independent basic service set 631IC integrated circuit 632ICA independent computer architecture 633ICB Internet Citizen's Band 634ICE in-circuit emulator 635ICE internal compiler error 636ICH I/O controller hub 637ICMP Internet Control Message Protocol 638ICT information and communications technology 639ICW initialization command word 640IDA Intel dynamic acceleration 641IDCMP Intuition direct communication message port 642IDE integrated development environment 643IDE integrated drive electronics 644IDPS intrusion detection [and] prevention system 645IDRP inter-domain routing protocol 646IDS intrusion detection system 647IDT interrupt descriptor table 648IE Internet Explorer 649IEC International Electrotechnical Commission 650IEEE Institute of Electrical and Electronics Engineers 651IESG Internet Engineering Steering Group 652IETF Internet Engineering Task Force 653IF intermediate frequency 654IFCM isochronous flow control mode 655IFF Interchange File Format 656IFS internal field separator 657IGD Internet gateway device 658IGMP Internet Group Management Protocol 659IGP interior gateway protocol 660IHV independent hardware vendor 661IKE Internet key exchange 662ILM internal loopback mode 663ILOM integrated lights-out management 664ILP instruction level parallelism 665IM instant messaging 666IMAP Internet Message Access Protocol 667IMC integrated memory controller 668IMCR interrupt mode configuration register 669IMR interrupt mask register 670IMS information management system 671IMSI international mobile subscriber identity 672INCITS InterNational Committee for Information Technology Standards 673IO input/output 674IOCTL input/output control 675IOMMU input/output memory management unit 676IOT Internet of Things 677IP Internet Protocol 678IP intellectual property 679IPC instructions per cycle 680IPC interprocess communication 681IPE integrated programming environment 682IPI intelligent peripheral interface 683IPI interprocessor interrupt 684IPL Initial Program Load 685IPL Interrupt Priority Level 686IPMB Intelligent Platform Management Bus 687IPMI Intelligent Platform Management Interface 688IPNG Internet Protocol, Next Generation 689IPS in-plane switching 690IPS intrusion prevention system 691IPSEC Internet Protocol Security 692IRC Internet Relay Chat 693IRDA infrared data association 694IRQ interrupt request 695IRQL interrupt request level 696IRR interrupt request register 697IRTF Internet Research Task Force 698IS information system 699ISA industry standard architecture 700ISA instruction set architecture 701ISDN integrated services digital network 702ISI inter-symbol interference 703ISM industrial, scientific, [and] medical 704ISN initial serial number 705ISO International Standards Organization 706ISOC Internet Society 707ISP Internet service provider 708ISR in-service register 709ISR interrupt service routine 710IST interrupt stack table 711ISV independent software vendor 712IT information technology 713ITB Intel Turbo Boost 714ITIL information technology infrastructure library 715ITP in-target probe 716ITSM IT service management 717IV initialization vector 718IVT interrupt vector table 719JBOD just a bunch of disks 720JFET junction [gate] field-effect transistor 721JIT just in time 722JPEG Joint Photographic Experts Group 723JRE Java Runtime Environment 724JSON JavaScript Object Notation 725JTAG joint test action group 726KASLR kernel address space layout randomization 727KB keyboard 728KB kilobyte 729KBD keyboard 730KBD kilobaud 731KCS keyboard controller style 732KLOC thousand lines of code 733KMS kernel-mode setting 734KPI kernel programming interface 735KVA kernel virtual address 736KVM kernel virtual machine 737KVM kernel virtual memory 738KVM keyboard, video, [and] mouse 739LAMP Linux Apache MySQL {Perl,PHP,Python} 740LAN local area network 741LAPIC local advanced programmable interrupt controller 742LAR load access rights 743LBA logical block addressing 744LBS location-based service 745LCD liquid crystal display 746LCP link control protocol 747LDA local delivery agent 748LDAP Lightweight Directory Access Protocol 749LDR light-dependent resistor 750LDT local descriptor table 751LE logical extent 752LED light emitting diode 753LELL low energy link layer 754LER label edge router 755LF line feed 756LF low frequency 757LFM lowest frequency mode 758LFN long file names 759LFO low-frequency oscillation 760LFS log-structured file system 761LFU least frequently used 762LHP loop heat pipe 763LIFO last in, first out 764LILO LInux LOader 765LILO last in, last out 766LINT local interrupt 767LIR local Internet registry 768LISP LISt Processor 769LISP Locator/ID Separation Protocol 770LKM {Linux,loadable} kernel module 771LKML Linux kernel mailing list 772LL load linked 773LL/SC load linked/store conditional 774LLC logical link control 775LLDP link layer discovery protocol 776LLF low level format 777LLMNR link-local multicast name resolution 778LLVM Low Level Virtual Machine 779LM long mode 780LMM link management mode 781LMP link management protocol 782LNO loop nest optimization 783LOC lines of code 784LOM lights-out management 785LPE Linux performance events 786LPC low pin count 787LPS local positioning system 788LRC longitudinal redundancy check 789LRM left-to-right mark 790LRO left-to-right override 791LRU least recently used 792LSAN Leak Sanitizer 793LSB Linux standards base 794LSB least significant {bit,byte} 795LSI large scale integration 796LSL load segment limit 797LSM log structured merge 798LSN Large Scale NAT 799LSN log sequence number 800LSR label switch router 801LTCC low temperature co-fired ceramic 802LTO linear tape-open 803LTO link time optimization 804LTR left to right 805LTR load task register 806LTR letter(-sized paper) 807LTS long term support 808LUA Lua Uppercase Accident 809LUN logical unit number 810LV logical volume 811LVM logical volume management 812LVT local vector table 813LVDS Low-Voltage Differential Signaling 814LWP light-weight process 815LZW Lempel Ziv Welch 816MAC mandatory access control 817MAC {media,medium} access control 818MAC message authentication {check,code} 819MADT multiple APIC descriptor table 820MB megabyte 821MBA multi-boot agent 822MBR master boot record 823MBS megabits per second 824MC memory controller 825MCA machine check architecture 826MCA MicroChannel architecture 827MCC multiversion concurrency control 828MCE machine check exception 829MCGA Multi-Color Graphics Array 830MCH memory controller hub 831MCM multi-chip module 832MCQ memory controlled queue 833MD machine-dependent 834MD-SAL model-driven service abstraction layer 835MDA mail delivery agent 836MDA Monochrome Display Adapter 837MDC Management Data Clock 838MDI Medium Dependent Interface 839MDI-X Medium Dependent Interface Crossover 840MDIO Management Data Input/Output 841MDMX MIPS Digital Media eXtension 842MDRAM multibank dynamic random access memory 843MESI modified, exclusive, shared, invalid 844MFC merge from current 845MFC Microsoft Foundation Classes 846MFM modified frequency modulation 847MFU most frequently used 848MI machine-independent 849MIB management information base 850MIC message integrity {check,code} 851MID mobile Internet device 852MIDI musical instrument digital interface 853MIF management information format 854MII media independent interface 855MIM man in the middle 856MIMD multiple instruction, multiple data 857MIME Multipurpose Internet Mail Extensions 858MIMO multiple input multiple output 859MIPS million instructions per second 860MIPS Microprocessor without Interlocked Pipeline Stages 861MISD multiple instruction, single data 862MIT Massachusetts Institute of Technology 863MITM man in the middle 864ML machine language 865ML machine learning 866ML mailing list 867ML markup language 868ML maximum likelihood 869MLC multi-level cell 870MLD multicast listener discovery 871MLHP micro loop heat pipe 872MMF multi-mode fiber 873MMIC monolithic microwave integrated circuit 874MMIO memory mapped input/output 875MMORPG massive multiplayer online role playing game 876MMU memory management unit 877MMX matrix math extension 878MMX multimedia extension 879MMX multiple math extension 880MO magneto-optical 881MOESI modified, owned, exclusive, shared, invalid 882MOF maximum operating frequency 883MOSFET metal-oxide-semiconductor field-effect transistor 884MOSI modified, owned, shared, invalid 885MP multi-platform 886MP multiplayer 887MP {multiprocessing,multiprocessor} 888MPEG moving picture experts group 889MPI message passing interface 890MPLS Multiprotocol Label Switching 891MPP massively parallel processor 892MPS memory pool system 893MPS multiprocessor specification 894MQTT Message Queuing Telemetry Transport 895MR modem ready 896MRU most recently used 897MS Microsoft 898MSAN Memory Sanitizer 899MSB most significant {bit,byte} 900MSC message sequence chart 901MSE mean square error 902MSF minutes seconds frames 903MSI message signaled interrupt 904MSI modified, shared, invalid 905MSR {machine state,model-specific} register 906MSS maximum segment size 907MSTP Multiple Spanning Tree Protocol 908MT machine translation 909MTA mail transfer agent 910MTBF mean time between failures 911MTP media transfer protocol 912MTRR memory type range register 913MTTF mean time to failure 914MTU maximum transmission unit 915MUA mail user agent 916MUD multi-user domain 917MVCC multiversion concurrency control 918MWE module width encoding 919MX mail exchange 920NACK negative acknowledgement 921NAN not a number 922NAPT Network Address Port Translation 923NAS network attached storage 924NAT network address translation 925NAV network allocation vector 926NC numerical control 927NCO numerically-controlled oscillator 928NCP Network Control Protocol 929NCQ native command queuing 930ND neighbor discovery 931NDFA nondeterministic finite automaton 932NE numeric error 933NEWS Network extensible Window System 934NFA nondeterministic finite automaton 935NFC near-field communication 936NFCI no functional change intended 937NFS network file system 938NFV network function virtualization 939NIA next instruction address 940NIC network information center 941NIC network interface card 942NIDS network intrusion detection system 943NIP network interface protocol 944NIPS network intrusion prevention system 945NIS network information service 946NIST National Institute of Standards and Technology 947NLS native language support 948NMI non-maskable interrupt 949NNTP Network News Transfer Protocol 950NOC network operations center 951NOP no operation 952NOS network operating system 953NP nondeterministic polynomial time 954NRND not recommended for new designs 955NRZ non-return to zero 956NSA nation-state adversary 957NSA no such agency 958NSA National Security Agency 959NTM non-deterministic Turing machine 960NTP Network Time Protocol 961NUMA non-uniform memory access 962NVRAM non-volatile random access memory 963NW not write-through 964NX no execute 965OAEP optimal asymmetric encryption padding 966OAM operations, administration, and {management,maintenance} 967OBO off by one 968OBOE off by one error 969OCL object constraint language 970OCR optical character recognition 971ODCM on-demand clock modulation 972ODT on-die termination 973OEM original equipment manufacturer 974OFB output feedback 975OFDM orthogonal frequency division multiplexing 976OFET organic field-effect transistor 977OLAP online analytical processing 978OLE object linking and embedding 979OLTP online transaction processing 980ONFI open nand flash interface 981OO OpenOffice 982OO object oriented 983OOB out of band 984OOE out of order execution 985OOM out of memory 986OOO OpenOffice.org 987OOP object oriented programming 988OOPS object oriented programming systems 989OOSE object oriented software engineering 990OPM operations per minute 991OPS operations per second 992OQL Object Query Language 993ORB object request broker 994ORM object-relational mapping 995OS operating system 996OSD open source definition 997OSF open software foundation 998OSI Open Source Initiative 999OSI open systems interconnection 1000OSPF open shortest path first 1001OSPM OS power management 1002OSS open sound system 1003OSS open source software 1004OSVW operating system visible workarounds 1005OTP one time password 1006OTP open telecom platform 1007OU organizational unit 1008OUI organizationally unique identifier 1009OWL Web Ontology Language 1010P2P PCI to PCI 1011P2P peer to peer 1012PA phase accumulator 1013PA physical address 1014PAAS platform as a service 1015PAC phase-amplitude converter 1016PAE physical address extension 1017PAL phase alternating line 1018PAL programmable array logic 1019PAM pluggable authentication modules 1020PAM pulse amplitude modulation 1021PAP password authentication protocol 1022PAT page attribute table 1023PAT port address translation 1024PATA parallel ATA 1025PAX portable archive exchange 1026PBE pending break encoding 1027PBE programming by example 1028PC personal computer 1029PC program counter 1030PCB printed circuit board 1031PCB process control block 1032PCB Protocol Control Block 1033PCC Portable C Compiler 1034PCD page-level cache disable 1035PCE path computation element 1036PCE performance-monitor counter enable 1037PCEP Path Computation Element Protocol 1038PCH platform controller hub 1039PCI peripheral component interconnect 1040PCM phase change memory 1041PCM pulse code modulation 1042PCMCIA Personal Computer Memory Card International Association 1043PCP Port Control Protocol 1044PD public domain 1045PDA personal digital assistant 1046PDA pushdown automaton 1047PDAG propositional directed acyclic graph 1048PDB power distribution board 1049PDF portable document format 1050PDM pulse-duration modulation 1051PDN pull-down network 1052PDP page {descriptor,directory} page 1053PDS product data sheet 1054PDU protocol data unit 1055PE protection enable 1056PEAP Protected EAP 1057PECI platform environment control interface 1058PEP protocol extension protocol 1059PER packed encoding rules 1060PFS perfect forward secrecy 1061PGAS partitioned global address space 1062PGE page global enable 1063PGP Pretty Good Privacy 1064PHB PCI host bridge 1065PHP PHP: Hypertext Preprocessor 1066PIC performance instrumentation counters 1067PIC position independent code 1068PIC programmable interrupt controller 1069PICNIC problem in chair, not in computer 1070PID process id 1071PIE position independent executable 1072PIL Priority Interrupt Level 1073PIM personal information manager 1074PIM platform-independent model 1075PIO programmed input/output 1076PIPT physically indexed, physically tagged 1077PIQ prefetch input queue 1078PIT programmable interrupt timer 1079PIV personal identity verification 1080PIX Private Internet eXchange 1081PKCS public-key cryptography standards 1082PKI public key infrastructure 1083PLC programmable logic controller 1084PLD programmable logic device 1085PLL phase locked loop 1086PLRU pseudo LRU 1087PLTM package level thermal management 1088PM power management 1089PM {phase,pulse} modulation 1090PMC performance monitoring counters 1091PME power management event 1092PMEG page map entry group 1093PMI performance monitoring infrastructure 1094PMIC power management integrated circut 1095PMI platform management interrupt 1096PMIO port-mapped input/output 1097PMT photo-multiplier tube 1098PMU performance monitoring units 1099PMU power management unit 1100PNG portable network graphics 1101PNP plug and play 1102POE power over ethernet 1103POF probability of failure 1104POP Post Office Protocol 1105POP power on password 1106POSIX Portable Operating System Interface [for Unix] 1107POST power on self test 1108POTS plain old telephone system 1109POWER Performance Optimization With Enhanced RISC 1110POWERPC Performance Optimization With Enhanced RISC - Performance Computing 1111PP pair programming 1112PPB PCI [to] PCI bridge 1113PPC PowerPC 1114PPC Power Performance Computing 1115PPI pixels per inch 1116PPM pages per minute 1117PPP Point-to-Point Protocol 1118PPPOA Point-to-Point Protocol over ATM 1119PPPOE Point-to-Point Protocol over Ethernet 1120PPU physics processing unit 1121PRAM Parameter RAM 1122PRBS pseudorandom bit sequence 1123PRG pseudorandom generator 1124PRF pseudorandom function [family] 1125PRML partial response, maximum likelihood 1126PRN pseudorandom {noise,number} 1127PRNG pseudorandom number generator 1128PROM programmable read only memory 1129PRP pseudorandom permutation 1130PRU Programmable Realtime Unit 1131PS PostScript 1132PSD power spectral density 1133PSE page size extensions 1134PSK phase shift keying 1135PSK pre-shared key 1136PSTN public switched telephone network 1137PSW program status word 1138PTE page table entry 1139PTLA pseudo top level aggregator 1140PTP page table page 1141PTV perceived target value 1142PU processing unit 1143PUC personal unblocking code 1144PUN physical unit number 1145PV physical volume 1146PVG physical volume group 1147PVI protected-mode virtual interrupt 1148PVST Per-VLAN Spanning Tree 1149PWM pulse width modulation 1150PXE preboot execution environment 1151QA quality assurance 1152QAM quadrature amplitude modulation 1153QAM quality assurance management 1154QBE query by example 1155QC quality control 1156QDI quasi delay insensitive 1157QCIF quarter common intermediate format 1158QOS quality of service 1159QVL qualified vendor list 1160R/O read only 1161R/W read/write 1162RA receiver address 1163RA remote assistance 1164RA resource affinity 1165RA router advertisement 1166RAD rapid application development 1167RAID redundant array of {independent,inexpensive} disks 1168RAM random access memory 1169RAS reliability, availability and serviceability 1170RAS remote access service 1171RAS restartable atomic sequence 1172RAS row address strobe 1173RBF radial basis function 1174RBT red-black tree 1175RC release candidate 1176RC remote control 1177RC run commands 1178RCS Revision Control System 1179RCS revision control system 1180RCU read, copy, update 1181RDB Rigid Disk Block 1182RDBMS relational database management system 1183RDF Resource Description Framework 1184RDM relational data model 1185RDMA remote direct memory access 1186RDRAM Rambus DRAM 1187RE regular expression 1188REST representational state transfer 1189RF radio frequency 1190RFI radio frequency interference 1191RFO request for ownership 1192RGB red green blue 1193RGBA red green blue alpha 1194RGMII reduced gigabit media independent interface 1195RH read hit 1196RHEL Red Hat Enterprise Linux 1197RHL Red Hat Linux 1198RIB routing information base 1199RIFF Resource Interchange File Format 1200RIP Raster Image Processor 1201RIP Routing Information Protocol 1202RIR regional Internet registry 1203RISC reduced instruction set {computer,computing} 1204RKM ROM Kernel Manual 1205RLE run length encoding 1206RLL run length limited 1207RLO right-to-left override 1208RM read miss 1209RMCP Remote Management Control Protocol 1210RMI remote method invocation 1211RMO Relaxed Memory Ordering 1212RMPM rapid memory power management 1213RMS root mean square 1214RMW read, modify, write 1215RNG random number generator 1216ROM read only memory 1217RPC remote procedure call 1218RPKI resource PKI 1219RPL requested privilege level 1220RPM revolutions per minute 1221RPN reverse Polish notation 1222RPVST Rapid Per-VLAN Spanning Tree 1223RR random replacement 1224RR round robin 1225RS relay station 1226RSA Rivest, Shamir, [and] Adleman 1227RSIP Realm Specific IP 1228RSN Robust Secure Network 1229RSS really simple syndication 1230RSS residual sum of squares 1231RSTP Rapid Spanning Tree Protocol 1232RT real time 1233RTC real time clock 1234RTC real time computing 1235RTF rich text format 1236RTL register transfer language 1237RTL resistor-transistor logic 1238RTL right to left 1239RTOS real time operating system 1240RTS request to send 1241RTT round trip time 1242RUP rational unified process 1243RW Rabin-Williams 1244RWM read-write memory 1245RX {receive,receiver} 1246S/PDIF Sony/Philips Digital Interface Format 1247SA security advisory 1248SA security association 1249SA source address 1250SA structured analysis 1251SAAS software as a service 1252SACD super audio compact disc 1253SAD security association database 1254SAL {service,system} abstraction layer 1255SAM serial access memory 1256SAM sum addressed memory 1257SAML security assertion markup language 1258SAN storage area network 1259SAP service access point 1260SAPIC streamlined advanced programmable interrupt controller 1261SASD structured analysis, structured design 1262SASI Shugart Associates System Interface 1263SASL simple authentication [and] security layer 1264SATA serial advanced technology attachment 1265SAX simple API for XML 1266SB sound blaster 1267SBU standard build unit 1268SC store conditional 1269SCA source code analyzer 1270SCADA supervisory control and data acquisition 1271SCC single chip cloud 1272SCC source code control 1273SCCS Source Code Control System 1274SCI scalable coherent interface 1275SCI system control interrupt 1276SCM software configuration management 1277SCM source code management 1278SCM storage-class memory 1279SCO synchronous connection orientated 1280SCP secure copy 1281SCSI Small Computer System Interface 1282SCTP Stream Control Transmission Protocol 1283SDEI software delegated exception interface 1284SDI symbol deinterleave 1285SDK software development kit 1286SDL Simple Declarative Language 1287SDL Simple Direct-media Layer 1288SDLC {software,system,systems} development life cycle 1289SDN software defined networking 1290SDP Session Description Protocol 1291SDRAM synchronous dynamic random access memory 1292SDS software defined storage 1293SDT syntax-directed translation 1294SEA synchronous external abort 1295SEGV segmentation violation 1296SEO search engine optimization 1297SES SCSI enclosure services 1298SFC sequential function chart 1299SFI simple firmware interface 1300SFI software fault isolation 1301SFTP SSH File Transfer Protocol 1302SFTP Serial File Transfer Protocol 1303SFTP Simple File Transfer Protocol 1304SGMII serial gigabit media independent interface 1305SGRAM synchronous graphics random access memory 1306SHA secure hash algorithm 1307SIDH supersingular isogeny Diffie-Hellman 1308SIEM security information and event management 1309SIF source input format 1310SIFS short inter-frame space 1311SIM subscriber identity module 1312SIMD single instruction, multiple data 1313SIMM single inline memory module 1314SIP Session Initiation Protocol 1315SIR signal-to-interference ratio 1316SIR slow infrared 1317SISD single instruction, single data 1318SLAAC stateless address auto-configuration 1319SLC single-level cell 1320SLDRAM synchronous-link dynamic random access memory 1321SLED single large expensive disk 1322SLI scalable link interface 1323SLI scan-line interleave 1324SLOC source lines of code 1325SLRU segmented LRU 1326SMA smart memory access 1327SMAF system management action field 1328SMAP Simple Mail Access Protocol 1329SMAP supervisor mode access prevention 1330SMART self-monitoring analysis and reporting technology 1331SMB Server Message Block 1332SMB system management bus 1333SMBIOS System Management BIOS 1334SMC system management controller 1335SMD storage module device 1336SMEP supervisor mode execution protection 1337SMF single mode fiber 1338SMI structure of management information 1339SMI system management interrupt 1340SMM system management mode 1341SMP symmetric multiprocessing 1342SMT simultaneous multithreading 1343SMTP Simple Mail Transfer Protocol 1344SMU system management unit 1345SNAP Sub-Network Access Protocol 1346SNIA Storage Networking Industry Association 1347SNMP Simple Network Management Protocol 1348SNR signal-to-noise ratio 1349SOA service oriented architecture 1350SOAP Simple Object Access Protocol 1351SOC system on chip 1352SOF start of frame 1353SOH start of header 1354SOHO small office/home office 1355SOL serial over LAN 1356SP service pack 1357SP stack pointer 1358SPA storage pool allocator 1359SPARC scalable processor architecture 1360SPARQL SPARQL Protocol and RDF Query Language 1361SPD security policy database 1362SPD serial presence detect 1363SPDIF Sony/Philips digital interface format 1364SPI serial peripheral interface 1365SPI stateful packet inspection 1366SPL system interrupt priority level 1367SPL spinlock 1368SPMD single process, multiple data 1369SPR special purpose register 1370SPT sectors per track 1371SQA software quality assurance 1372SQCIF sub quarter common intermediate format 1373SQL Structured Query Language 1374SRAM static random access memory 1375SRC sample rate conversion 1376SRP SCSI RDMA protocol 1377SS self-snoop 1378SS stack segment 1379SSA static single assignment 1380SSAP source service access point 1381SSB single-sideband modulation 1382SSD solid state drive 1383SSE streaming SIMD extensions 1384SSFDC solid state floppy disc card 1385SSH secure shell 1386SSI server side includes 1387SSID service set identifier 1388SSL secure sockets layer 1389SSP stack smashing protection 1390STC software thermal control 1391STD state transition diagram 1392STOMP Streaming Text Oriented Messaging Protocol 1393STP Spanning Tree Protocol 1394STP shielded twisted pair 1395SUN Stanford University Network 1396SUS Single Unix Specification 1397SUT system under test 1398SVG scalable vector graphics 1399SVGA Super Video Graphics Array 1400SVI {switch,switched} virtual interface 1401SVM secure virtual machine 1402SVM support vector machine 1403SVR System V Release 1404SVS Separate Virtual Space 1405SWF Shockwave Flash 1406SWIG simplified wrapper [and] interface generator 1407SYR symbol timing recovery 1408TA test assertion 1409TA transmitter address 1410TAI international atomic time 1411TAO track at once 1412TAOCP The Art of Computer Programming 1413TAP Test Anything Protocol 1414TAS test and set 1415TB terabyte 1416TCB trace capture buffer 1417TCB trusted computing base 1418TCC thermal control circuit 1419TCL tool command language 1420TCP Transmission Control Protocol 1421TCQ tagged command queueing 1422TDC time [to] digital converter 1423TDD test-driven development 1424TDD time division duplex 1425TDM time division multiplexing 1426TDMA time division multiple access 1427TDOA time difference of arrival 1428TDP thermal design {point,power} 1429TECO Text Editor and Corrector 1430TFT thin film transistor 1431TFTP Trivial File Transfer Protocol 1432TIAS try it and see 1433TIFF tagged image file format 1434TITS try it to see 1435TK temporal key 1436TKIP Temporal Key Integrity Protocol 1437TLA top level aggregator 1438TLB translation lookaside buffer 1439TLD top level domain 1440TLS thread local storage 1441TLS transport layer security 1442TM Turing machine 1443TM thermal monitor 1444TMDS transition minimized differential signaling 1445TMO timeout 1446TOD time of day 1447TOS terms of service 1448TOS trusted operating system 1449TOS type of service 1450TP transaction processing 1451TPI tracks per inch 1452TPM transactions per minute 1453TPM trusted platform module 1454TPR task priority register 1455TPS transactions per second 1456TPS transmission parameters signaling 1457TR task register 1458TR token ring 1459TRL timing recovery loop 1460TRNG true random number generator 1461TS terminal services 1462TS time series 1463TS time stamp 1464TS transport stream 1465TSAN Thread Sanitizer 1466TSC time stamp counter 1467TSD time stamp disable 1468TSDB time series database 1469TSL test, set, lock 1470TSO time sharing option 1471TSO Total Store Ordering 1472TSP Time-Stamp Protocol 1473TSP Tunnel Setup Protocol 1474TSP time synchronization protocol 1475TSP traveling salesman problem 1476TSS task state segment 1477TTL time to live 1478TTL transistor-transistor logic 1479TTM translation table maps 1480TTY teletype 1481TUI {terminal,text-based,textual} user interface 1482TX {transmit out,transmitter} 1483TXG transaction group 1484TZ time zone 1485UAC user {access,account} control 1486UAF use-after-free 1487UART universal asynchronous receiver/transmitter 1488UAT user acceptance testing 1489UB undefined behavior 1490UBSAN Undefined Behavior Sanitizer 1491UC uncacheable 1492UCS uniform-cost search 1493UDMA ultra DMA 1494UDO ultra density optical 1495UDP User Datagram Protocol 1496UEFI unified extensible firmware interface 1497UFS Unix File System 1498UGA universal graphics adapter 1499UI unit interval 1500UI user interface 1501UICC universal integrated circuit card 1502UID unique identifier 1503UID user identifier 1504UL upload 1505UMA uniform memory access 1506UMA upper memory area 1507UMB upper memory block 1508UML unified modeling language 1509UMPC ultra-mobile PC 1510UPNP universal plug and play 1511UPS uninterruptible power supply 1512URI uniform resource identifier 1513URL uniform resource locator 1514URN uniform resource name 1515USART universal synchronous/asynchronous receiver/transmitter 1516USB universal serial bus 1517USWC uncacheable speculative write combining 1518UT unit test 1519UTC coordinated universal time 1520UTP unshielded twisted pair 1521UUCP Unix-to-Unix Copy Protocol 1522UUID universally unique identifier 1523UUOC useless use of cat 1524UUT unit under test 1525UX user experience 1526VA vertical alignment 1527VA virtual address 1528VA volt-ampere 1529VAX virtual address extension 1530VB Visual Basic 1531VCA variable-gain amplifier 1532VCC common collector voltage 1533VCF voltage-controlled filter 1534VCM virtual channel memory 1535VCO voltage-controlled oscillator 1536VCS version control system 1537VESA Video Electronics Standards Association 1538VFO variable-frequency oscillator 1539VG volume group 1540VGA Video Graphics Array 1541VHDCI very high density cable interconnect 1542VID {VLAN,voltage level} identifier 1543VIM Vi IMproved 1544VIPT virtually indexed, physically tagged 1545VIVT virtually indexed, virtually tagged 1546VLAN virtual local area network 1547VLIW very long instruction word 1548VLSI very large scale integration 1549VLSM variable length subnet mask 1550VM virtual {machine,memory} 1551VME virtual mode extension 1552VMX vector multimedia extensions 1553VMX virtual machine extensions 1554VOD video on demand 1555VPN virtual private network 1556VR virtual reality 1557VRAM video random access memory 1558VRF virtual routing and forwarding 1559VRM voltage regulator module 1560VRRP Virtual Router Redundancy Protocol 1561VSTP VLAN Spanning Tree Protocol 1562VTP VLAN Trunking Protocol 1563W watt 1564W3C World Wide Web Consortium 1565WAMP Web Application Messaging Protocol 1566WAN wide area network 1567WAP Wireless Application Protocol 1568WAP wireless access point 1569WDM Windows Driver Model 1570WDDM Windows Display Driver Model 1571WDT watchdog timer 1572WEP Wired Equivalent Privacy 1573WFI wait for interrupt 1574WFQ weighted fair queuing 1575WH write hit 1576WIFI wireless fidelity 1577WLAN wireless local area network 1578WM write miss 1579WMI Windows Management Instrumentation 1580WOL Wake-on-LAN 1581WOM Wake-on-Modem 1582WOR Wake-on-Ring 1583WORM write once read many 1584WP WordPerfect 1585WP word processor 1586WP write protect 1587WPA Wi-Fi Protected Access 1588WPA2 Wi-Fi Protected Access II 1589WPS Wi-Fi Protected Setup 1590WRAM window random access memory 1591WS web services 1592WTC write through caching 1593WWAN wireless wide area network 1594WWW world wide web 1595WYSIAYG what you see is all you get 1596WYSIWYG what you see is what you get 1597XBAR crossbar 1598XDMCP X Display Manager control protocol 1599XER XML encoding rules 1600XGA Extended Graphics Array 1601XHR XMLHttpRequest 1602XIP execute in place 1603XML Extensible Markup Language 1604XOR exclusive or 1605XP extreme programming 1606XSI X/Open System Interface 1607XSL extensible stylesheet language 1608XSS cross site scripting 1609XT extended technology 1610XUL XML user interface language 1611YACC yet another compiler compiler 1612YAML YAML ain't markup language 1613YANG yet another next generation 1614YAWPFAPR you are welcome; please file a problem report 1615YP Yellow Pages 1616YTD year to date 1617ZAP ZFS attribute processor 1618ZBR zone bit recording 1619ZFOD zero-filled on demand 1620ZFS zettabyte file system 1621ZIF zero insertion force 1622ZIFS zero insertion force socket 1623ZIL ZFS intent log 1624ZMA zone multicast address 1625ZPL ZFS Posix layer 1626ZVOL ZFS Volume 1627