57 results

U.2    Wikipedia  PCPartPicker Forums       

Ubuntu A Linux distribution based off of Debian.   Wikipedia  Website       

Ubuntu 16.04  Released April 21, 2016.  Ubuntu Insights         

ultimate route Routing table entry that has a next-hop IPv4 address or an exit interface. (Dynamic routes or local routes.)            

uname Unix command to display the name and version of the computer. Use ver or winveron Windows.            

unequal-cost load balancing Distributes traffic over network interfaces even if they are different distances (metrics). Supported by EIGRP.            

unfiltered port Nmap port state where an ACK scan returns an RST packet on the scanned port. The unfiltered state means that a port is accessible, but Nmap is unable to determine whether it is open or closed.   Nmap         

unicast (One to One.) Sending a packet from one host to an individual host. Unicast ranges from but some address blocks are reserved for other special uses.   Wikipedia         

Unicode standard character encoding   Wikipedia         

Unicornscan Developed to assist security testers in conducting tests on large networks and to consolidate many of the tools needed for large-scale endeavors. Optimizes UDP scanning beyond the capabilities of any other port scanner.   Website  sectools.org       

Unified Modeling Language (UML) Used for modeling object oriented programs.            

Uniform Resource Identifier (URI) Can be a URL or a URN.   Wikipedia         

Uniform Resource Locator (URL)    Wikipedia         

Uniform Resource Name (URN)    Wikipedia         

Uniform Service Order Code (USOC)             

Unique Identifier (UID)    Wikipedia         

Unique Local Address (ULA) These addresses should not be routable in the global IPv6. Unique local addresses are in the range of FC00::/7 to FDFF::/7.  Defined in RFC 4193 October, 2005.  Wikipedia  RFC 4193       

Unity Shell for the GNOME desktop environment from Canonical. First released June 9, 2010.  Website  Wikipedia       

UNIVersal Automatic Computer (UNIVAC)    Wikipedia         

Universal Character Set (UCS)    Wikipedia         

Universal Character Set Transformation Format - 32-bit (UTF-32)    Wikipedia         

Universal Character Set Transformation Format - 8-bit (UTF-8)    Wikipedia         

Universal Disk Format (UDF) Open file system. Typically used on optical media.   Wikipedia         

Universal Mobile Telecommunications System (UMTS) Third generation mobile cellular system for networks based on the GSM standard.   Wikipedia         

Unlock-ADAccount PowerShell cmdlet used to unlock an Active Directory account.   TechNet         

unordered pair (aka: set) {x, y}   Wikipedia         

Unified Extensible Firmware Interface (UEFI)    Wikipedia         

Unified Threat Management (UTM)    Wikipedia         

Unit Identification Light (UID) Helps physically identify an individual server.   HP Community         

Universal Plug and Play (UPnP) UDP port 1900   Wikipedia  PDF       

Universal Serial Bus (USB) Standard connector that replaced the plethora of serial and parallel IO.  Designed to be "Plug-and-Play" hot swappable and self-configuring. Supports up to 127 connected devices through a single bus (port) at one time.  First introduced January 1996.  Wikipedia         

Universal Windows Platform (UWP) One app on any screen size. Originally Windows Runtime in Windows 8.  Windows Dev Center  Microsoft Developer Network       

UNIX An operating system developed by Bell Labs with Ken Thompson and Dennis Ritchie. Originally written in the PDP-7 assembly language. OS X and Linux are two popular operating systems based off UNIX.   Wikipedia         

UNIX Shell    Wikipedia         

UNIX-to-UNIX Copy Program port 540            

unordered list (ul) HTML tag that defines a unordered list marked with bullets. Used with the li tag to create the list.   W3Schools         

Unshielded Twisted Pair (UTP) Cable found in many Ethernet networks and telephone systems. terminated with an RJ connector, Usually RJ-45 (8P8C) or RJ-11 (6P2C). TIA/EIA-568 is the standard for wire color codes to the pinouts for Ethernet cables.            

up/down status up/protocol down. Layer 2 issue: (keepalive, encapsulation, clocking)            

up/up status up/protocol up.             

Updatable View Can be used to update attributes in the base tables that are used in the view.            

uptime The amount of time a computer has been on since the last reboot. Can be viewed on UNIX-like systems with the uptime command. Use wmic os get lastbootuptime (written as: yyyymmddhhmmss.nnn) for Windows.   Wikipedia         

USB 1.0 (aka: Low Bandwidth, Low Speed) Up to 1.5Mbps transfer rate. First introduced January 1996.  Wikipedia         

USB 1.1 (aka: Full Speed) Up to 12Mbps (1.5MBps) transfer rate. Max cable length is 3 meters (18 meters if using the maximum of five hubs). Released in August 1998.  Wikipedia         

USB 2.0 (aka: High Speed) Up to 480Mbps (60MBps) transfer rate. Max cable length is 5 meters (30 meters if using the maximum of five hubs). Released in April 2000.  Wikipedia         

USB 3.0 (aka: SuperSpeed) Up to 5Gbps transfer rate. Max cable length is 3 meters (18 meters if using the maximum of five hubs). Released November 12, 2008.  Website         

USB 3.1 Gen 1 Preserves the existing SuperSpeed transfer rate under a new label USB 3.1 Gen 1, and introduces a new SuperSpeed+ transfer mode, USB 3.1 Gen 2 with the maximum data signaling rate to 10 Gbit/s (1250 MB/s, twice the rate of USB 3.0). Released in July 2013.  Website  Wikipedia       

USB 3.1 Gen 2 Up to 10Gbps transers rate.   Website  Wikipedia       

USB 3.2 Specification for USB. Maximum transfer speed of 2GBps (gigabytes per second). Doubles the speed of existing USB Type-C cables. Published September 22, 2017.  USB-IF  Tom's Hardware  Ars Technica     

USB Type-A             

USB Type-B             

USB Type-C Reversible 24-pin connector. Standardized August 12, 2014.  Wikipedia  AnandTech       

User Datagram Protocol (UDP) Layer 4 connectionless protocol that has unreliable delivery. (Does not acknowledge if the data is received.) Uses less overhead than TCP.   Wikipedia         

user interface How a user can interact with a device. This can be   Wikipedia         

user-group-other (UGO) Acronym for file permissions.             

useradd Bash command to add a user account.   Linuxers         

uTorrent (?Torrent) A P2P application.   Wikipedia