f
F connector (aka: F-type) Coaxial RF connector commonly used for cable television and modems, usually with RG-6/U cable or the older RG-59/U. Invented by Eric E. Winston in the early 1950s. Wikipedia
F# (F Sharp) Programing language developed by Microsoft. Released May 2005. Wikipedia Microsoft Developer Network Microsoft (F# 1.0.8 released)
f.lux Software that makes your display warmer and more pleasing to your eyes. Website
F8 2019 April 30 - May 1 Website
Facebook Instant Articles Released May 15, 2015.
failover capabilities The ability of a device to switch from a non-functioning module, service or device, to a functioning one with little or no break in service. Netacad
Fall Creators Update (Version 1709) Released October 17, 2017. Windows Blogs Wikipedia
False Acceptance Rate (FAR) (aka: Type II error) Incorrectly granting access to an unauthorized user.
False Rejection Rate (FRR) (aka: Type I error) Denying access to a legitimate authorized user. Webopedia
favicon Icon that identifies a website in a web browser or shortcut. Wikipedia
fc Command that compares two files or sets of files, and displays the differences between them.
FE80::/10 IPv6 link local address. Wikipedia Cisco
Feasible Condition (FC) When a neighbors RD is less than this router's FD to the same destination network.
Feasible Distance (FD) The lowest calculated metric to reach the destination network.
Feasible Successor (FS) next after successor (backup path)
Fedora The upstream version of RHEL. Wikipedia
FF01::1 All nodes multicast address IANA
FF02::2 All routers multicast address IANA
FF02::A EIGRP ipv6 multicast IANA
fi Closes an if statement in Bash. Stack Overflow
Fiber Channel (FC) Wikipedia
Fiber To The x (FTTx) Generic term for optical fiber in the last mile of broadband connections. Usually just called Fiber To The Home (FTTH). Wikipedia
fiber-optic Type of cable consisting of a thin flexible transparent glass or plastic fiber slightly thicker than a human hair. Can transmit from 100Mbps to 10Gbps for several miles. Uses pulses of light to transmit data making it immune to wiretapping and electrical interference. Two cable types: Single-Mode Fiber (SMF) and Multi-Mode Fiber (MMF). First developed in the 1970s. Wikipedia
Fibonacci cube A network topology for parallel computing that has roots in recursion and the Fibonacci number. Wikipedia
Fibonacci number 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144,... Wikipedia
field Wikipedia
File Allocation Table (FAT) file system Wikipedia
File Allocation Table 32 (FAT32) File system. Maximum file size is 4GB minus 1 byte. Wikipedia
File Checksum Integrity Verifier (FCIV) Command-prompt utility that computes and verifies MD5 or SHA-1 cryptographic hash values of files. Microsoft Support
File Classification Infrastructure (FCI)
File permissions Tells who can access a file or directory and what they can do with it. Wikipedia
File Server Resource Manager (FSRM)
file system How data is stored. Wikipedia
File Transfer Protocol (FTP) Protocol used for transferring files between systems. Wikipedia
File Transfer Protocol Secure (FTPS) (aka: FTPES, FTP-SSL) Secure version of FTP that runs over SSL or TLS connections. Wikipedia
FileMaker Pro Crossplatform DBMS. Wikipedia Website
filesystem Wikipedia
filtered port Nmap port state that might indicate that a firewall is being used. Nmap cannot determine whether the port is open because packet filtering prevents its probes from reaching the port. Nmap
FIN (1 bit) Packet sent to both parties to end a TCP three both parties to end a TCP three-way handshake. Wikipedia
Final Fantasy Fantasy role-playing game. First released for the NES in Japan December 18, 1987 and in North America July 12, 1990. Wikipedia
find Command that searches for a text string in a file or files.
findstr Command that searches for strings in files.
Finite-State Machine (FSM) Wikipedia
Firefox Open source web browser designed and maintained by Mozilla. First released September 23, 2002. Website Wikipedia
Firefox 1.5 Dropped support for Mac OS X 10.1 and earlier. Announced as Firefox 1.1 June 23, 2005. Released as Firefox 1.5 November 30, 2005 Wikipedia
Firefox 2.0 Released October 24, 2006. Wikipedia
Firefox 3.0 Released June 17, 2008. Wikipedia
Firefox 3.5 Released June 30, 2009. Wikipedia
Firefox 3.6 Released January 21, 2010. Wikipedia
Firefox 4.0 Released March 22, 2011. Wikipedia
Firefox 43 Released December 15, 2015. Wikipedia
Firefox 44 Released January 26, 2016. Wikipedia
Firefox 45 Released March 8, 2016. Wikipedia
Firefox 46 Released on April 26, 2016. Wikipedia
Firefox 47 Released June 7, 2016. Wikipedia
Firefox 48 Released August 2, 2016. Wikipedia
Firefox 49 Released September 20, 2016. Wikipedia
Firefox 50 Released November 15, 2016 Wikipedia
Firefox 51.0 Released on January 24, 2017 Wikipedia
Firefox 52 (ESR) Released March 7, 2017. Wikipedia
Firefox 52.0.1 Released alongside Firefox 52.0.1 ESR March 17, 2017. Wikipedia
Firefox 52.0.2 Released alongside Firefox 52.0.2 ESR March 28, 2017. Wikipedia
Firefox 53 Released April 19, 2017. Wikipedia
Firefox 53.0.1 Released April 27, 2017. Wikipedia
Firefox 53.0.2 Released May 5, 2017. Wikipedia
Firefox 53.0.3 Released May 19, 2017. Wikipedia
Firefox 54 Released June 13, 2017. Wikipedia
Firefox 54.0.1 Released June 29, 2017. Wikipedia
Firefox 55 Released August 8, 2017. Wikipedia
Firefox 55.0.1 Released August 10, 2017. Wikipedia
Firefox 56 Released September 28, 2017. Wikipedia
Firefox 56.0.1 Released October 9, 2017. Wikipedia
Firefox 56.0.2 Released October 26, 2017. Wikipedia
Firefox 57 (Firefox Quantum) Released on November 14, 2017. Wikipedia
Firefox 57.0.1 Released November 29, 2017. Wikipedia
Firefox 57.0.2 Released December 7, 2017. Wikipedia
Firefox 57.0.3 Released December 28, 2017. Wikipedia
Firefox 58 Released January 23, 2018. Wikipedia
Firefox 59 Released March 13, 2018. Wikipedia
Firefox 60 Released alongside Firefox 60 ESR May 9, 2018. Wikipedia
Firefox 61 Released January 23, 2018. Wikipedia
Firesheep Wikipedia codebutler
firewall Separates protected areas from non-protected areas. Filters incoming and outgoing traffic. Software or hardware based. Different types include packet filtering, stateful, or application layer firewall. Wikipedia
FireWire 400 (aka: IEEE 1394-1995) Supports data transfer up to 400Mbps. Can have either 4 or 6 pins. 1394a standardized the 4-conductor alpha connector developed by Sony and trademarked as "i.LINK". Wikipedia
FireWire 800 (aks: IEEE 1394b-2002) Apple's name for the 9-conductor "S800 bilingual" version of the IEEE 1394b standard. Capable or data transfers of 800Mbps. Wikipedia
firmware Stored in non-volatile memory. Wikipedia
First Hop Redundancy Protocol (FHRP) Examples include Cisco HSRP. Wikipedia
First In, First Out (FIFO) Memory management technique. Wikipedia
first responder Responsible for:
| Securing the scene |
| Notifying the incident response team |
| Determining the scope and impact |
five nines Reliability standard with only 5.26 minutes of downtime per year. Wikipedia
Flash Plug-in maintained by Adobe. Originally developed by Macromedia. Acquired by Adobe in 2005. Wikipedia
flash memory Non-volatile memory used for the OS and other system files in networking devices. (IOS is copied form flash to RAM during boot up.) Based on electrons rather than magnetism.
Floating Point Unit (FPU) Performs decimal arithmetic. Wikipedia
floating static route Backup route to a static or dynamic route. To test a floating static route, shutdown the main link and the route should appear in the routing table.
floating-point number Data type. Wikipedia
flow control Manages the flow of data from the sender to ensure the receiver is not overwhelmed. Wikipedia TechTarget
Fast Page Mode DRAM (FPM DRAM)
Field-Programmable Gate Array (FPGA) Wikipedia
Floating-point Operations Per Second (FLOPS) More accurate that IPS. Wikipedia
flood guard Limits the number of devices that can connect to a switch port. Once the maximum number of MAC address is exceeded, the port shuts down. Professor Messer
floppy disk Legacy storage media. Named after its flexible nature. Wikipedia
Floppy Disk Drive (FDD) Reads floppy disks. Typically designated as the A: drive or B: if the PC had two drives. Wikipedia
Flow Label Part of an IPv6 header. Wikipedia
flowchart Displays steps to solve a problem. Wikipedia
Fluke Manufactures testing equipment for electronics. Founded in 1948. Wikipedia Website
flux Lines of flux repel each other and never cross.
foo Commonly used as a variable name for anything. RFC 3092
FOR DOS command that runs a specified command for each file in a set of files.
for loop Loops for a set number of times. Wikipedia
ForEach-Object PowerShell cmdlet. TechNet
foreground (fg) Send a job to the foreground. Wikipedia
foreign key Values are required to match the primary key of another table. Proper use of foreign keys is crucial to controlling data redundancy. Wikipedia
forest Complete collection of Active Directory (AD). Website Wikipedia
fork bomb Replicating process. Wikipedia
form Used to gather information.
Form Feed (FF) Page-break ASCII character.
FORMAT DOS command that formats a disk for use.
Format Set of PowerShell cmdlets that allow you to control which properties are displayed for particular objects. TechNet
forms Office Support (Introduction to forms)
Fortran Programming language. First manual for Fortran was published October 15, 1956. First Fortan compiler delivered in April 1957. Wikipedia
Forward Explicit Congestion Notification (FECN) Frame Relay congestion-notification bit Wikipedia
forward proxy Hides the clients from the server by forwarding the message to the server. Can be configured for caching content filtering, and firewall capability. Wikipedia
forwarding database One of the three OSPF databases. Contains the routing table.
Forwarding Information Base (FIB) (aka: CAM table) Wikipedia
Forza Motorsports First released in North America May 3, 2005. Wikipedia
fping Ping sweep tool used to ping multiple IP addresses simultaneously. First published by Roland Schemers in 1992. Website Wikipedia
Fragment Offset Field in an IPv4 packet. Wikipedia
fragmentation When an intermediate device, usually a router, must split up a packet if it is transferring it to a medium with a smaller MTU.
Frame Data at Layer 2. Generic frame field:
[ Frame start | Addressing | Type | Control | Data | Error Detection ]
Frame Check Sequence (FCS) Verifies that a frame was received correctly without error.
Frame encoding technique Converts streams of data bits into a predefined code. Distinguish data bits from control bits. Identify where the frame starts and ends.
Frame Relay Packet-switched WAN. Operates at Layer 1 and Layer 2. NBMA. Wikipedia Cisco Wireshark Wiki
Frame Relay Access Device (FRAD) Router connected to a Frame Relay network.
Frame Subtype
| 0x00 | Association request frame |
| 0x01 | Association response frame |
| 0x02 | Reassociation request frame |
| 0x03 | Reassociation response frame |
| 0x04 | Probe request frame |
| 0x05 | Probe response frame |
| 0x08 | Beacon frame |
| 0x0A | Disassociation frame |
| 0x0B | Authentication frame |
| 0x0C | Deauthentication frame |
Frame Type
| 0x0 | Management Frame |
| 0x1 | Control Frame |
| 0x2 | Data Frame |
Framework Class Library (FCL) Wikipedia
Free Berkeley Software Distribution (FreeBSD) Wikipedia Website
Free Lossless Audio Codec (FLAC) Does not compress the audio file. Released July 20, 2001 Wikipedia
Free Network Attached Storage (FreeNAS) FreeBSD designed for NAS use bundled in a web GUI. Wikipedia Website FreeBSD Forums
frequency The number of complete cycles in one second. Measured in hertz.
Frequency-Division Multiple Access (FDMA)
Frequency-hopping spread spectrum (FHSS)
Front Side Bus (FSB) (aka: memory bus, system bus, local bus, host bus) Computer communication interface (bus) that connects the CPU to the controller chipset. Often used in Intel-chip-based computers during the 1990s and 2000s. Replaced by HyperTransport, Intel QuickPath Interconnect or Direct Media Interface in modern CPUs. Wikipedia
FTP bounce attack Security attack that leverages the PORT command.
FTP Server Serves files over FTP. Wikipedia Ubuntu Documentation
FTYPE DOS command that displays or modifies file types used in file extension associations. Wikipedia
full duplex Two-way commutation. (cell phone)
Fully Qualified Domain Name (FQDN) An address that identifies the hostname, domain, and top-level domain of a device. Wikipedia
fully specified static route Both output interface and the next hop IP address are specified.
function Instructions that perform a task. Basic syntax: function-name () {commands } Wikipedia
fuzzing (aka: fuzz testing) Application vulnerability testing technique that sends invalid or unexpected data to the application, with the intent to see if any security vulnerabilities exist. Wikipedia
FX Microprocessor series from AMD. First released October 12, 2011. Wikipedia
FX-6300 CPU from AMD. Released October 23, 2012 CPU World