299 results

C Indicates a directly connected network in a routing table.   Wikipedia         

C Programming language developed by modifying the B language. Machine-independent "portable assembler".   Wikipedia         

C# Object oriented programming language. Released July 2000  Wikipedia         

C++ Object-oriented programming language. Introduced in 1983.  Website  Wikipedia       

cable Made up of two or more wires.   Wikipedia         

Cable Modem (CM)             

Cable Modem Termination System (CMTS)             

cable television (CATV) (originally stood for: Community Access Television, Community Antenna Television) System of delivering television programming to paying subscribers via radio frequency (RF) signals transmitted through coaxial cables, or in more recent systems, light pulses through fiber-optic cables.   Wikipedia         

cache Reduces the main memory access time.   Wikipedia         

cacls Windows command that displays or modifies ACLs of files.   Wikipedia         

Caesar cipher Simple substitution cipher.   Wikipedia         

call Command that calls one batch program from another.   Microsoft         

Call Admission Control (CAC)             

Call Expressions Evaluate then apply the operator to the operand.

operator(operand, operand)

   Wikipedia  YouTube - UC Berkeley        

candidate key Minimal superkey. Key that does not contain a subset of attributes that is itself a superkey.            

Canonical Name (CNAME) Sometimes referred to as an alias.            

capacitance Generally rated in farads (F), microfarads (μF), nanofarads (nF) or picofarads (pF). To find the total:

connected in parallelvalues add
connected in seriesreciprocal method

capacitor Oppose a change of voltage. Capacitance determined by:

Stores energy in an electric field. Current flows only while the capacitor is charging or discharging. Charge and discharge at an exponential rate.   Wikipedia  YouTube (Make:)       

CareKit Open-source framework from Apple.  Released March 21, 2016.  Website  Wikipedia       

caret ^ Regular expression that matches the beginning of a line. Example: ^foobar will find any line beginning with foobar. Begins an anchor regular expression. '^*$' Can be used to negate characters with brackets. [^]   Wikipedia         

Carol Shaw    Wikipedia         

Carriage Return (CR)             

Carriage Return and Line Feed (CRLF) newline            

Carrier Sense Multiple Access (CSMA) Protocols based on CSMA are non-deterministic. (Media independent.)            

Carrier Sense Multiple Access with Collision Detection (CSMA/CD)    Wikipedia         

Carrier-Sense Multiple Access with Collision Avoidance (CSMA/CA) Can increase latency in a WLAN. Adds a random delay before transmitting data in an attempt to avoid collisions. Sends a message across the media before it sends a frame.   Wikipedia         

carving Process of data recovery where residual info does not exist for restoration.   Wikipedia         

Cascading Style Sheet (CSS) Web design language used for styling a web page.   Wikipedia  Khan Academy       

Catalyst Brand of network switch from Cisco.   Website  Wikipedia       

Category X cable (Cat X) Type of unshielded twisted pair (UTP) cable. 

Cat 1 Used for telephone wiring. 1 MHz maximum transmission, which is not suitable for data.
Cat 2 4 MHz maximum transmission. (4Mbits)
Cat 3 Used for telephone wiring. Was also used for computer networks during the 1990s.
Cat 4 20 MHz maximum transmission. (16Mbps)
Cat 5/5e 100 MHz maximum transmission. Up to 1000BASE-T (Gigabit Ethernet).
Cat 6 250 MHz maximum transmission. Up to 10GBASE-T (10-Gigabit Ethernet).
Cat 7
Cat 8
  Wikipedia (Cat 3)  Wikipedia (Cat 5)  Wikipedia (Cat 6)  Wikipedia (Cat 7)   

Cathode Ray Tube (CRT)    Wikipedia         

cd Command that displays the name of or changes the current directory.   Wikipedia         

CDC 6600 Mainframe supercomputer from Control Data Corporation. Delivered January 14, 1965 to CERN.  Wikipedia  CERN       

Celeron CPU made by Intel. Considered a low-end processor.   Wikipedia         

cell Stores data.            

Central Office (CO) Local service provider building that connects the CPE to the provider network.   Wikipedia         

Central Processing Unit (CPU) The main processor or "engine" of a computer.   Wikipedia         

Certbot Automatically enable HTTPS on your website with EFF's Certbot, deploying Let's Encrypt certificates.   Website  Wikipedia       

Certificate Authority (CA)             

Certificate Revocation List (CRL) List of digital certificates that have been revoked by the issuing certificate authority (CA) before their scheduled expiration date and should no longer be trusted. Defined in RFC 5280 May 2008.  Wikipedia  RFC 5280       

CES 2018  January 8, 2018 - January 11, 2018.  Website  Wikipedia  Circuit Breacker Live Stream     

CES 2019  January 8-11, 2019.  Website  Wikipedia       

CES 2020  January 7-10, 2020  Website  Wikipedia       

Challenge Handshake Authentication Protocol (CHAP) Performs a one-way authentication for a remote access connection. Authentication is performed through a three-way handshake (challenge, response, acceptance message) between a server and a client, without sending credentials across the network. Specified in RFC 1994, August 1996.  Wikipedia  RFC 1334  RFC 1994     

change mode (chmod) chmod UNIX command used to change access permissions. Example:

chmod -x script_nameMakes a script executable
   Wikipedia  Linux.org  chmod Tutorial     

Change on Write (COW)    Wikipedia         

Channel Service Unit/Data Service Unit (CSU/DSU) Layer 1 device. Digital leased lines require both a CSU and a DSU, even if in separate devices. CSU terminates digital signal. DSU converts line frames into frames readable by the LAN.   Wikipedia         

character A data type.   Wikipedia         

character encoding    Wikipedia  W3Schools       

chargeback Policy used by IT departments to allocate and/or bill the costs associated with each department's or division's usage. As of 2011, the chargeback mechanisms are often controversial in organizations.  Wikipedia         

Charles Babbage    Wikipedia  Computer History Museum       

charset    W3Schools         

Chatsworth    Website         

chcp DOS command that displays or sets the active code page number.            

CHDIR Displays the name of or changes the current directory.   Wikipedia         

checksum A redundancy check. Catches data transmition errors. Typically 32 or 64 bits.   Wikipedia         

Cheetah (Mac OS X 10.0)   Wikipedia         

Chief Information Security Officers (CISO)             

children (subdirectory) Directories that are within the current directory.            

chipset    Wikipedia         

CHKDSK DOS command that checks a disk and displays a status report.   Wikipedia         

CHKNTFS DOS command that displays or modifies the checking of disk at boot time.   Wikipedia         

Chocolatey Package manager for Windows.   Website         

Chosen-Ciphertext Attack             

Chosen-Plaintext Attack             

Chris Allegretta Creator of the text editor nano.   Wikipedia         

Christmas Tree EXEC First widely disruptive computer worm. Discovered December 9, 1987.  Wikipedia  Malware Wiki       

Chrome Web browser developed by Google. First released September 2, 2008.  Website  Wikipedia       

Chrome OS Operating system developed by Google. Based on Linux. Uses the Chrome web browser as the user interface. First released June 15, 2011.  Website  Wikipedia       

Chromium Open source web browser project which is the foundation for Google Chrome.. Frist released September 2008.  Website  Wikipedia       

chsh Linux command to change the shell.            

Chuck Robbins CEO of Cisco.   Wikipedia         

Cinebench Benchmarking tool.   Website  Wikipedia       

cipher An algorithm for encrypting and decrypting. Methods include: Transposition, Substitution, One-time pad.   Wikipedia         

Cipher Block Chaining (CBC) DES block cipher. Most widely used mode of DES. Invented by Ehrsam, Meyer, Smith and Tuchman in 1976.  Wikipedia         

Cipher feedback (CFB)             

CipherShed Encryption replacement for the late TrueCrypt.   Wikipedia  Website       

ciphertext encrypted text.            


(h,k) center
r = radius
   Wolfram MathWorld  Wikipedia       

circuit-switched network Uses a dedicated path during transmission. PSTN and ISDN are two examples of a circuit-switched WAN.   Wikipedia         

circumference The perimeter of a circle.            

Cisco Networking company based in San Jose, California. Founded in December of 1984. Name derived from San Francisco where Cisco first started.  Wikipedia         

Cisco Adaptive Security Appliance (ASA) Firewall from Cisco. Two firewall modes of operation: routed mode and transparent mode. Basic configs:

 Replaced the Cisco PIX.  Wikipedia  Netacad       

Cisco Adaptive Security Device Manager (ASDM) Browser-based, Java applet used to configure and monitor the software on a Cisco ASA.   Netacad         

Cisco Adaptive Wireless IPS Software             

Cisco AnyConnect Secure Mobility Solutions             

Cisco ASA 5505 Firewall made by Cisco. Released August 31, 2006. EoL announced July 18, 2012.  Website  Wikipedia       

Cisco ASA 5510 Firewall made by Cisco. Released May 4, 2005.  Website  Data Sheet       

Cisco AutoSecure Can automatically configure CBAC, security banner, and enable secret password.            

Cisco Catalyst 2960-X Series of network switch from Cisco. Announced June 4, 2013. Released July 2013.  Website  Wikipedia  Cisco Blog     

Cisco Catalyst 2960X-24PD-L 24-port network switch from Cisco. Released May 24, 2013.  Website         

Cisco Catalyst 2960X-24PS-L 24-port network switch from Cisco. Released May 24, 2013.  Website         

Cisco Catalyst 2960X-24PSQ-L 24-port network switch from Cisco. Released May 24, 2013.  Website         

Cisco Catalyst 2960X-24TD-L 24-port network switch from Cisco. Released May 24, 2013.  Website         

Cisco Catalyst 2960X-24TS-L 24-port network switch from Cisco. Released May 24, 2013.  Website         

Cisco Catalyst 2960X-24TS-LL 24-port network switch from Cisco. Released May 24, 2013.  Website         

Cisco Catalyst 2960X-48FPD-L 24-port network switch from Cisco. Released May 24, 2013.  Website         

Cisco Certified Entry Networking Technician (CCENT)    Website  Wikipedia       

Cisco Certified Internetwork Expert (CCIE)    Wikipedia         

Cisco Certified Network Associate (CCNA)    Wikipedia         

Cisco Certified Network Professional (CCNP)    Wikipedia         

Cisco Common Classification Policy Language (C3PL) Configures ZBF policies.   Cisco         

Cisco Connection Online (CCO) Account used on cisco.com.   Cisco         

Cisco Encryption Technology (CET)             

Cisco Express Forwarding (CEF) Default forwarding mechanism used on IOS 12.0 or later.   Wikipedia         

Cisco Identity Service Engine             

Cisco IronPort             

Cisco IronPort Email Security Appliance             

Cisco IronPort Web Security Appliance             

Cisco Live San Diego 2019  June 9-13, 2019.  Website         

Cisco Live US 2018  June 10-14 in Orlando, FL.  Website         

Cisco NAC Agent (NAA)             

Cisco NAC appliance    Cisco         

Cisco NAC Appliance (formerly: Cisco Clean Access (CCA)) Network Admission Control (NAC) system developed by Cisco used to secure a computer network.   Wikipedia  Cisco       

Cisco NAC Manager (NAM)             

Cisco NAC Server (NAS)             

Cisco Network Admission Control (NAC) Allow access and enforces security policy            

Cisco Network Foundation Protection (NFP) framework

control plane Routes data correctly. Protects against DoS attacks and provides bandwidth control.
management plane Management traffic from Telnet, SSH, TFTP, FTP, NTP, AAA, SNMP, syslog, TACACS+, RADIUS, and NetFlow.
data (forwarding) plane Forwards data. typically user generated data.

Cisco Networking Academy    Netadad         

Cisco PIX  One of the first NAT appliances. Developed in 1994.  Wikipedia  History of the PIX Firewall       

Cisco ScanSafe Cloud Web Security             

Cisco Secure Access Control System             

Cisco SecureX architecture

Delivery Mechanisms
Next-generation Endpoint
Policy Management Consoles
PScanning Engines
Security Intelligence Operations (SIO) Cloud-based service that connects global threat information.

Cisco Talos One of the largest commercial threat intelligence teams in the world.   Website  Cisco       

Cisco Unified Computer System (Cisco USC) Line of scalable servers form Cisco. Announced March 2009. First installed September 1, 2009.  Wikipedia  Cisco Press Release       

Cjdns Network protocol.   Wikipedia  Website       

class Group of objects.   Wikipedia         

class (.class) Java class file   Wikipedia         

Class A address block -   Wikipedia  Wikipedia       

Class B address block -   Wikipedia  Wikipedia       

Class C address block -   Wikipedia  Wikipedia       

Class D address block Multicast addresses.            

Class E address block Experimental addresss.            

class libraries Pre-defined classes for common tasks.            

classful Only Class A, B, or C address. (,,   Wikipedia         

Classic Windows App (CWA) (aka: Win32 app) Application that runs on the traditional Windows desktop.            

classless Any class of address. (/8, /25, /30...)            

Classless Inter-Domain Routing (CIDR)    RFC 1519         

Cleanroom suit (aka: bunny suit)   Wikipedia         

clock signal    Wikipedia         

clear Command that clears the screen.            

Clear-ADAccountExpiration PowerShell cmdlet used to clear the expiration date for an Active Directory account.   TechNet         

cleartext (plaintext)            

client Device that accesses a server.   Wikipedia         

Client Access Server (CAS)    TechNet         

Client-side scripting    Wikipedia         

clobber Unintentionally overwrite a file.   Wikipedia         

clock rate The rate data is transmitted. Configured on DCE interfaces.   Wikipedia         

clock set Set the time and date. Use show clock to display the time in IOS.            

clock skew An issue along parallel communication where information does not arrive at the same time.   Wikipedia         

closed port Nmap port state that does not allow entry or access to a service. A closed port is accessible (it receives and responds to Nmap probe packets), but there is no application listening on it. Not vulnerable to an attack.   Website         

closed|filtered Nmap port state. This state is used when Nmap is unable to determine whether a port is closed or filtered. It is only used for the IP ID idle scan.   Nmap         

closure Property of relational operators that permits the end use of relational algebra operators on existing tables (relations) to produce new relations.            

cloud computing Off-premise pool of computer resources that can be brought up or down at will. Typically housed in a data center.    Wikipedia  Netacad       

cloud computing deployment model Four types: private, public, community, and hybrid.   Wikipedia  Netacad  IBM developerworks Blog     

cls DOS command that clears the screen.            

Cluster Shared Volumes (CSV) fixed     Wikipedia       

cmd DOS command that starts a new instance of the Windows command interpreter.            

Cmdlet Commands used in PowerShell. Follow a Verb-Noun naming convention. (i.e. Get-Help.)   Wikipedia  Microsoft Developer       

CNext (cnext.exe) Radeon Settings. File path: C:\Program Files\AMD\CNext\CNext\cnext.exe            

co (.co) A top level domain for Columbia            

coaxial    Wikipedia         

Code Access Security (CAS) Part of the .NET framework.   Wikipedia         

Code Red Computer worm. Released July 13, 2001. Isolation July 15, 2001.  Wikipedia.         

Code-Division Multiple Access (CDMA)    Wikipedia         

Codec    Wikipedia         

Collaboration Meeting Room (CMR) Collaboration tool combining video, voice, and content sharing.   Cisco  YouTube       

collapsed core model Core and distribution layers collapsed into a single device.   YouTube         

collision When two or more demands are made simultaneously on equipment that can handle only one at any given instant. (i.e. collision domain)   Wikipedia         

collision When two distinct pieces of data have the same hash value.   Wikipedia         

collision domain Physical network segment where data packets may collide with one another while being sent. CSMA/CD and CSMA/CA can be used to detect or avoid collisions on Ethernet or wireless LANs respectively.   Wikipedia         

color DOS command that sets the default console foreground and background colors. (color a, color b2...)            

column Each database table column represents an attribute. Each column has a distinct name.            

column list Represents one or more column names separated by commas. May also include computed columns, aliases, and aggregate functions.            

com (.com) A generic top level domain for a business or industry.            

Comit    Wikipedia         

Comma-Separated Values (CSV)    Wikipedia  RFC 4180       

Command (⌘) Key found on Apple keyboards. Similar functionality to the Windows Key.            

Command Prompt (cmd.exe) CLI Shell for Windows.   Wikipedia         

Command-Line Interface (CLI) Allows a user to input text commands into a computer. Based off of DOS.   Wikipedia         

Command-Line Interpreter (CLI) Interprets commands inputted by a user.   Wikipedia  Wikipedia       

COMMAND.COM Shell for DOS and the command line interpreter on Windows 95, Windows 98 and Windows ME.   Wikipedia         

Commercial Resupply Services Mission 10 (CRS-10) SpaceX's Falcon 9 rocket carried the Dragon spacecraft to low-Earth orbit to deliver critical cargo to the International Space Station for NASA. Launched from NASA's Kennedy Space Center in Florida February 19, 2017.  Website  Wikipedia       

Commodore 64 8-bit home computer from Commodore International. Released August 1982.  Wikipedia         

Commodore Amiga 1000 (aka: A1000) First personal computer from Commodore. Released July 23, 1985.  Wikipedia         

Commodore-64 Scene Data Base (CSDB)             

Common Address Redundancy Protocol (CARP) Open standard for first-hop redundancy. Provides functionality similar to VRRP and to Cisco's HSRP.   Wikipedia         

Common Business-Oriented Language (COBOL) programming language   Wikipedia         

Common Gateway Interface (CGI) Standard environment for web servers to interface with executable programs installed on the server that generate web pages dynamically.   Wikipedia         

Common Interface    Wikipedia         

Common Language Infrastructure (CLI) Developed by Microsoft.   Wikipedia         

Common Language Runtime (CLR) Virtual machine component of Microsoft's .NET framework that manages the execution of .NET programs.   Wikipedia         

Common Name (CN)    TechNet  YouTube (Microsoft MCSA/MCSE Learning Channel)       

Common Unix Printing System (CUPS)  First released release June 9, 1999.  Wikipedia         

Common Vulnerabilities and Exposure (CVE) Database of security vulnerabilities.   Website  Wikipedia       

Common-Channel Interoffice Signaling (CCIS)    Wikipedia         

Common-Channel Signaling (CCS)    Wikipedia         

Community Antenna Television (CATV)             

community strings Plaintext passwords. Two types; read-only (ro) and read-write (rw).            

COMP Compares the contents of two files or sets of files.            

COMPACT DOS command that displays or alters the compression of files on NTFS partitions.            

Compact Disc (CD) Optical disc. Typically 700MB.    Wikipedia         

Compact Disc File System (CDFS)    Wikipedia         

CompactFlash (CF)             

Compaq  Founded February 14, 1982. Acquired by HP in 2002.  Wikipedia         

Compaq Portable One of the first 100% IBM PC compatible systems. Announced November 4, 1982  Wikipedia         

Compare-Object (aliases: compare, diff) PowerShell cmdlet that compares two sets of objects. Example:

Compare-Object $foo $bar

comparison operator

greater than > -gt
less than < -lt
greater than or equal to >= -ge
less than or equal to <= -le
not euqal to NOT IS NOT
like (matches a pattern) LIKE
   MySQL Documentation         

Compiler Translates source code into machine code the computer can understad.   Wikipedia         

Compiling The process of translating source code into machine code. Any syntax errors will be found during this step.   Wikipedia         

Complementary Metal-Oxide-Semiconductor (CMOS) Type of memory. Typically used to store a BIOS configuration. Backed up with a battery.   Wikipedia         

Completely Automated Public Turing test to tell Computers and Humans Apart (CAPTCHA)    Wikipedia         

Completely Fair Scheduler (CFS) Process scheduler in Linux.   Wikipedia         

Complex Instruction Set Computing (CISC) The opposite of RISC. Originated in the 1960's.  Wikipedia         

component video When used without any other qualifications the term component video usually refers to analog YPBPR component video with sync on luma. Typically uses three RCA plugs; red, green, and blue.   Wikipedia         

composite entity (aka: bridge entity, associative entity) Designed to transform a M:N relationship into two 1:M relationships. Composite entity's primary key comprises at least the primary keys of the entities that it connects.            

composite key Multiple-attribute key.            

composite video Type of video connection. Commonly used in RCA connectors.   Wikipedia         

CompTIA A+ 220-901 & 220-902  Released December 15, 2015.  Website         

CompTIA Cybersecurity Analyst (CSA+)  Released February 15, 2017.  Website         

CompTIA Network+  Released February 28, 2015.  Website         

CompTIA Security+  Released May 1, 2014.  Website         

Compute Node Kernel (CNK) Node level operating system for the IBM Blue Gene supercomputer.   Wikipedia         

Computer Emergency Response Team (CERT) [aka: Computer Emergency Readiness Team, Computer Security Incident Response Team (CSIRT)] Expert group that handles computer security incidents. USA CERT created by the Defense Advanced Research Projects Agency (DARPA) and run by the Software Engineering Institute (SEI) at the Carnegie Mellon University. CERT name first used in 1988 by the CERT Coordination Center (CERT-CC) at Carnegie Mellon University (CMU).  SEI Website  Wikipedia       

Computer Management (compmgmt.msc)   Website  Wikipedia       

Computer Systems Research Group (CSRG)    Wikipedia         

Computer-Generated Imagery (CGI)    Wikipedia         

Computex Computer expo in Taipei. First expo in 1981.  Website  Wikipedia       

Computex 2017  May 30 - June 3  Website  Wikipedia       

Computex 2018  June 5 - June 9  Website  Wikipedia       

concatenation (cat) Can show one or more files together in the same output. The command split can separate files while cat can merge files.   Wikipedia  YouTube       

confidentiality (encryption) Message can't be read.            

congestion control 3 frame-relay congestion-notification bit. (FECN, BECN, )   Wikipedia         

conic section

   Wolfram MathWorld  Wikipedia       

connection oriented Must establish a connection before sending data.   Wikipedia         

console cable Connects through the console port to a host for configuring the device over CLI.            

constant-current transformer (aka: current regulators) Generally used to provide power to series connected loads.            

containerization (aka: Operating-system-level virtualization) Used to isolate an application. Containers run a single program and all its dependencies.   Wikipedia         

Content Delivery Network (CDN) Globally distributed network of proxy servers deployed in multiple data centers.   Wikipedia         

Content Security and Control (CSC) Adds anti-malware capabilities to a Cisco ASA.   Website  Netacad       

Content Security and Control Security Services Module (CSC-SSM)    Netacad         

Content-Addressable Memory (CAM)    Wikipedia         

Content-Addressable Memory (CAM) table MAC table   Wikipedia         

Context-Based Access Control (CBAC)             

Context-Free Grammar (CFG)    Wikipedia         

Control And Provisioning of Wireless Access Points (CAPWAP)    Wikipedia         

control structure    Wikipedia         

Controlled media access (controlled access) Devices take turns accessing the media with a token. Can be inefficient with too many devices.            

converged network One that transports multiple types of traffic such as voice, video, and data. Most modern netowrks are converged.            

convergence The process of failing over from one route to a backup route.            

CONVERT DOS command that converts FAT volumes to NTFS.             

Cooler Master Computer hardware manufacturer from Taiwan. Founded in 1992.  Website  Wikipedia       

copy Command that copies one or more files to another location in DOS or IOS. Use cp for Bash.            

copy on write (COW) Data is not copied until a write is attempted.   Stack Overflow   Wikipedia       

Core Layer The backbone layer between networks. Everything must be fast in this layer.   Wikipedia  Netacad  Netacad     

Core Temp Monitor CPU temperature.   Website         

corrective controls (after the event) Limit the extent of any damage caused by the incident e.g. by recovering the organization to normal working status as efficiently as possible.   Wikipedia         

correlated subquery Subquery that executes once for each row in the outer query.            

Corsair Computer peripherals and hardware company headquartered in Fremont, California. Founded in 1994.  Website  Wikipedia       

CORSAIR DOMINATOR PLATINUM Special Edition Torque  Released May 11, 2017.  Website         

coulomb Measure of charge.            

Counter Mode CBC-MAC Protocol (CCMP)    Wikipedia         

cp Command that copies one or more files to another location in Bash. (copy for DOS.)            

CPU cache Fast memory that is used to store data going between main memory and the CPU. Predicts what the CPU will ask for next and prefetches information before it is asked. Each level feeds the next (i.e. Level 3 feeds Level 2 and Level 2 feeds Level 1.)

L1 Internal cache built into the processor's silicon wafer, or die.
L2 Can be itegrated on die, backside bus (BSB), or on the motherboard.
L3 Typically integrated on the motherboard.
L4 Uncommon, generally only on DRAM.
   Wikipedia  Techopedia  CPU-World     

CPU socket Where the CPU is inserted on the PCB. Allows the CPU to easily be placed or replaced without soldering.   Wikipedia         

CPU-Z Freeware that shows information about the hardware of a computer such as CPU and Motherboard specifications.   Website  Wikipedia       

Cramer's rule Explicit formula for the solution of a system of linear equations with as many equations as unknowns, valid whenever the system has a unique solution. Named after Gabriel Cramer who published the rule in 1750.  Wikipedia         

Cray One of the early supercomputers.   Wikipedia  Website       

createinstallmedia Terminal command used to create a bootable installer for macOS.   Apple Support         

Creators Update (aka: Redstone 2 (RS2)) Codename for the third major update build of Windows 10. Early download available April 5, 2017. Released April 11, 2017.  Wikipedia         

crimper Tool used to make twisted pair network cables.            

Critical Structure Corruption BSOD error message that indicates that one or more Windows system files have been modified or corrupted.   Tom's Hardware         

Cross-Site Scripting (XSS) Security vulnerability typically found in web applications. Allows attackers to inject client-side scripts into web pages viewed by other users. May be used by attackers to bypass access controls such as the same-origin policy.   Wikipedia         

Crossover Cable (T568A to T568B) An uncommon networking cable. Directly connect like devices together.    Wikipedia         

crosstalk Interference between twisted-pair copper wires caused by the magnetic field around the adjacent pair of wire.   Wikipedia         

crunchbang A Linux distribution. Based on Debian.            

cryptanalysis Cracking code. Necessary to prove an algorithm is not vulnerable.   Netacad         

Crypto ACL             

Crypto Map             

cryptographic hash function Should have the following properties:


cryptographic key symmetric keys, digital signatures, hash keys.            

cryptographic keys Several types of cryptographic keys can be generated including:

Symmetric keys Can be exchanged between two routers supporting a VPN
Asymmetric keys Used in HTTPS applications
Digital signatures Used when connecting to a secure website.
Hash keys Used in symmetric and asymmetric key generation, digital signatures

cryptography    Wikipedia  Khan Academy       

CryptoLocker ransomware trojan   Wikipedia         

cryptology The science of making and breaking secret codes.   Wikipedia         

Crysis  First released November 13, 2007.  Website  Wikipedia  Wikipedia (Series)     

Crysis 2  First released March 22, 2011.  Website  Wikipedia       

Crysis 3  First released February 19, 2013.  Website  Wikipedia       

Crysis Warhead  First released September 16, 2008.  Website  Wikipedia       

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current (I)    Wikipedia         

Current Branch (CB) Windows update/support branch for Windows 10 Home, Pro, Education, and Enterprise.   Wikipedia         

Current Branch for Business (CBB) Windows update/support branch for Windows 10 Pro, Education, and Enterprise.   Wikipedia         

Customer Premises Equipment (CPE) Devices and wiring located on the enterprise edge, connected to a carrier link.   Wikipedia         

Cyan, Magenta, Yellow, Key (black) (CMYK) color model    Wikipedia         

Cyanogen Mobile operating system based on Android. Cyanogen OS is what comes pre-installed on phones such as the OnePlus One. CyanogenMod is a replacement firmware that installs on top of Android. Fist released July 1, 2009.  Website  Twitter       

Cyclic Redundancy Check (CRC) Similar to a hash.   Wikipedia