s
S Identifies a static route created to reach a specific network in a routing table.
S-Video (aka: separate video, Y/C) Signaling standard for standard definition video, typically 480i or 576i. It transmits video signals over a cable by dividing the video information into two separate signals: one for color (chrominance), and the other for brightness (luminance). Better image quality than composite video, but has lower color resolution than component video. Uses a 4, 7, or 9 pin Mini-DIN connector. Designed in 1987. Wikipedia
SA database (SADB) Maintains security associations. Netacad
Safari Web browser from Apple. irst released January 7, 2003. Version 1.0 released June 23, 2003. Website Wikipedia
Samba A file type of file server. Samba documentation Ubuntu documentation
Samsung Founded March 1, 1938. Wikipedia
Samsung Galaxy Note 8 Smartphone from Samsung.
| Display: |
|
| CPU: |
|
| Memory: | 6 GB LPDDR4X RAM |
| Storage: |
|
| Camera: |
|
| MSRP: | $929.99 |
Samsung Galaxy S8 Smartphone from Samsung Announced March 29, 2017. Released April 21, 2017. Website Wikipedia
Samsung Galaxy S9 Smartphone from Samsung. Announced February 25, 2018 at Mobile World Congress (MWC) 2018. Website Wikipedia
sandbox Security mechanism for separating running programs, usually in an effort to mitigate system failures or software vulnerabilities from spreading. Isolated space where untested code and experimentation can safely occur separate from the production environment. Wikipedia
Sandy Bridge Microarchitecture codename from Intel. First released January 5, 2011. Wikipedia
SANS Institute Wikipedia Website
sans-serif Wikipedia
SC.exe TechNet
scalar Indicates magnitude only. Wikipedia
schema Defines attributes for all Active Directory (AD) objects. Wikipedia
schematics Simplified representation of an electronic circuit. YouTube (Make:)
scratch space (aka: scratch drive) Logical or physical space dedicated to temporarily work with data. Commonly used in programs that need more memory than the available RAM such as Adobe Photoshop. Wikipedia
scrum Iterative and incremental agile software development framework for managing product development. Wikipedia
scutil Command used on a Mac to set the hostname. OS X Man Pages
scytale Possibly one of the first transposition cipher tools. Wikipedia
SeaTools Hard drive analysis tool from Seagate. First released January 30, 2007. Website Wikipedia
Second Level Address Translation (SLAT) (aka: nested paging) Hardware-assisted virtualization technology. Wikipedia
Secure Copy (SCP) (TCP port 22) Secure way to copy files between two computers. Example: scp SourceFile user@host:directory/TargetFile Wikipedia John Veldboom
Secure Device Manager (SDM) Management software for Cisco routers
Secure Digital eXtended Capacity (SDXC) Announced January 2009. Wikipedia
Secure Digital High Capacity (SDHC) Announced January 2006. Wikipedia
Secure European System for Applications in a Multivendor Environment (SESAME) European-developed authentication protocol that can provide for single sign-on capability. It is not widely used and does not use tickets for authentication.
Secure Hash Algorithm (SHA)
| SHA-1 | (Legacy) Uses a 160-bit secret key. |
| SHA-2 | SHA-224, SHA-256, SHA-384, SHA-512 |
| SHA-3 |
Secure Hash Algorithm 1 (SHA-1) Cryptographic hash function which produces a 160-bit hash value known as a message digest. part of several widely used security applications and protocols, including TLS and SSL, PGP, SSH, S/MIME, and IPsec. Can provide data integrity in a VPN. Designed by the United States National Security Agency (NSA). not been considered secure since 2005. Wikipedia
Secure Hash Standard (SHS) Wikipedia
Secure Shell (SSH) A more secure form of telnet that uses port 22 instead of port 23 as in the case of telnet. Cisco Pluralsight blog
Secure Shell (SSH) Configuration Can be configured on a Cisco device with a;
- hostname
- domain name
- type of SSH key, such as RSA
- transport input ssh on the vty lines
//example |
hostname carter |
aaa new-model |
username cisco password 0 cisco |
ip domain-name rtp.cisco.com |
crypto key generate rsa |
ip ssh time-out 60 |
ip ssh authentication-retries 2 |
line vty 0 4 |
transport input SSH |
Secure Sockets Layer (SSL) Can be used to established remote-access VPN connections. Initially published as SSL 2.0 February 1995. Wikipedia Instant SSL by Comodo
Secure Sockets Layer Certificate (SSL Certificate) YouTube
secure software development model
| Requirements | Requirements for different security functions are determined. |
| Testing | Software is measured or tested against security, functionality, and performance requirements. (secure code review, application fuzzing, vulnerability assessments, and penetration testing.) |
| Design | Security functionality is designed into the application. |
| Implementation | Security requirements are validated as implemented in the application. |
Secure/Multipurpose Internet Mail Extensions (S/MIME) Wikipedia
Security Alert Error: "The name on the security certificate is invalid or does not match the name of the site." Issued to: *.btrll.com. Description: Ads displayed in Yahoo Mail have an invalid SSL certificate. Solution: Block the advertisements with an ad blocker. Yahoo Help Community
security and functionality relationship As security increases, functionality decreases. As resources decrease, both functionality and security decrease.
Security and Maintenance (Formerly Action Center and Windows Security Center) Microsoft Support Wikipedia
Security Assertion Markup Language (SAML) Used for web application login. Wikipedia
Security Association (SA) Part of the IPsec suite used to negotiate the cryptographic parameters between two devices in an ISAKMP session. Performed after AH or ESP has been selected. Maintained by a SADB. Wikipedia Netacad
security authentication failure rate
security controls Risk likelihood and impact should directly determine how much is budgeted for security controls. Can be classified by when the occur or according to their nature.
| Security Functions: |
|---|
| deterrent |
| preventive |
| detective |
| compensating |
| corrective |
| Security Controls: |
|---|
| administrative |
| technical |
| physical |
Wikipedia
Security Device Manager (SDM) Cisco
Security Event Manager (SEM) Real-time monitoring of logs and events generated by devices or software on the network. Wikipedia
Security Identifier (SID) Unique value of variable length used to identify a trustee. MSDN Wikipedia
Security Information and Event Management (SIEM) Combines Security Information Management (SIM) and Security Event Management (SEM) software products and services. Analyzes security alerts from networking equipment and software in real-time. Can aggregate and correlate data, allowing you to organize it into valuable information. Splunk is an example of SIEM. Coined by Mark Nicolett and Amrit Williams of Gartner in 2005. Wikipedia
Security Information Management (SIM) Central location for long-term storage analysis of log data. Wikipedia
Security Operations Center (SOC) Wikipedia
Security Services Module (SSM)
Sega Japanese video game company. Founded in 1940 as Service Games. Renamed to Sega June 3, 1960. Wikipedia
Segmentation Dividing a data stream into small pieces.
SELECT SQL statement that returns a set of records from one or more tables. Main data retrieval command in SQL. Wikipedia
self induction When a coil induces voltage into itself.
Self-Monitoring, Analysis and Reporting Technology (S.M.A.R.T) (often written as SMART) Keeps track of the health of a hard disk drive (HDD) or solid-state drive (SSD). Wikipedia
self-similarity (fractals) Wikipedia
Semiconductor Wikipedia
sequence control structure Series of statements that follow one another.
Sequoia Supercomputer from IBM Installed at the Lawrence Livermore National Laboratory (LLNL) in 2011. Wikipedia
Sergey Brin Co-founded Google with Larry Page. Born August 21, 1973. Website Wikipedia
serial Sends information in a single stream, one at a time. (bidirectional)
Serial Advanced Technology Attachment (SATA) Released in 2003. Wikipedia
Serial Attached SCSI (SAS) Point-to-point serial protocol used for storage devices. Wikipedia
Serial Line Internet Protocol (SLIP) standard protocol for point-to-point serial connections using TCP/IP Netacad
Serial Link Address Resolution Protocol (SLARP)
server A host used to serve information to other clients.
Server Core Stripped-down version of Windows server managed from the command line. First released in Windows Server 2008. Wikipedia
Server Message Block (SMB) Application-layer protocol mainly used for providing shared access to files, printers, serial ports, and miscellaneous communications between nodes on a network. Primarily used in Windows networks. Wikipedia
Service Level Agreement (SLA) Agreement between two parties that specifies the level of service and support. Can outline QoS parameters for packets going through a provider. Wikipedia
service sequence-numbers Service on networking devices that puts sequence numbers in syslog messages.
Service Set Wikipedia
Service Set Identifier (SSID) (aka: BSSID) Associated with the MAC address on a wireless Access Point (AP). Identify logical networks (including extended service sets) and serve as the "network name". Wikipedia
services.msc Services in Windows.
Serving Area Interface (SAI) Outdoor enclosure or metal box that allows access to telecommunications wiring. Wikipedia
session hijacking (aka: cookie hijacking) Intercepting and taking over an in-progress communications session between two hosts. Wikipedia
Session Initiation Protocol (SIP) (port 5060) Wikipedia YouTube
Session Layer (OSI Layer 5) Establishes and controls data communication between applications operating on two computers. Wikipedia
SET Displays, sets, or removes Windows environment variables.
Set-ADAccountExpiration PowerShell cmdlet used to set the expiration time of a user, computer, or service account. TechNet
Set-ADUser PowerShell cmdlet used to modify an Active Directory user. TechNet
Set-Date PowerShell command that changes the date or time. TechNet
Set-Item WSMan:\localhost\Client\TrustedHosts -Value hostname -Force
Set-ItemProperty PowerShell cmdlet. Can be used to change registry values. Introduced in PowerShell 3.0. TechNet
Set-NetConnectionProfile PowerShell cmdlet that changes the network category of a connection profile. Introduced in Windows Server 2012 and Windows 8. TechNet
Set-NetIPAddress PowerShell cmdlet used to change an IP address. TechNet
Set-SmbServerConfiguration PowerShell cmdlet used to disable SMB1. Set-SmbServerConfiguration -EnableSMB1Protocol $false Microsoft Support
Set-VHD PowerShell cmdlet used to modify a virtual hard disk. TechNet
Set-VM PowerShell cmdlet used to configure a virtual machine. Website
SETLOCAL Begins localization of environment changes in a batch file.
Seymour Cray The father of supercomputing. September 28, 1925 - October 5, 1996 Wikipedia
Shebang #! Starts a script in UNIX. Wikipedia
Shell Provides a user interface for accessing an operating system's services. Wikipedia
Shell Script Program that is run by the UNIX shell. Wikipedia Ubuntu documentation
Shielded Twisted Pair (STP) A type of twisted pair cabling with a layer of braided foil shielding surrounding the wires to reduce electrical interference. Wikipedia
shift Shifts the position of replaceable parameters in batch files. Microsoft documentation
Shift + F5 Refresh without looking at local cache. Wikipedia
Shift key Key that modifies or "shifts" the keys on a keyboard to another function such as capital letters. Wikipedia
Short Message Service (SMS) Wikipedia
short text data type that can contain any characters with a maximum of 255.
shoulder surfing Looking over someone's shoulder as they type in a password.
show commands Commands in Cisco IOS that show.., stuff.
show arp | IOS command to show the ARP table. |
show interfaces | |
show ip eigrp neighbors | |
show ip eigrp topology | |
show ip interface brief | Command to show a list of interfaces and any IPv4 addresses that might be assigned to them. Use show ipv6 interface brief to show IPv6 interfaces |
show ip ospf | process ID, router, id, OSPF SPF, OSPF, area information |
show ip ospf database | Shows LSDB area, link id |
show ip ospf interface | Shows details about all OSPF enabled interfaces the router ID. |
show ip ospf interface interface id | Details about a particular OSPF enabled interface |
show ip ospf interface brief | Concise OSPF-related information of OSPF-enabled interfaces, OSPF process id, area, cost, brief |
show ip ospf neighbor | OSPF adjacencies and the router IDs of those routers |
show ip protocols | Shows the protocols on a router. OSPF process ID, router ID, advertised networks, neighbors the router is receiving updates from, and the administrative distance. |
show ip route | Command used to display IPv4 routing table of a router |
show ip route eigrp | |
show ip route ospf | Shows only OSPF routes in the routing table |
show ipv6 route | Shows the IPv6 routing table on a network device |
show running configuration | Shows the running configuration file |
show flash | Contents of the flash |
show boot | Location of the configuration file |
show version | Current IOS version |
shutdown Command that turns a network devices interface off.
Shutdown /o Go to the advanced boot options menu and restart the computer. Must be used with /r option. Introduced in Windows 8. MSDN The Windows Club
sideloading Installing applications from a source other than the operating system's default app store. Wikipedia
Sierra (macOS 10.12) Released September 20, 2016. Website Wikipedia
SIGGRAPH 2017 July 30, 2017 - August 3, 2017 at the Los Angeles Convention Center. Event Website Main Website Wikipedia
signal-to-noise ratio (SNR) Wikipedia
Silicon Wikipedia
simple attribute Attribute that cannot be subdivided.
Simple Mail Transfer Protocol (SMTP) (TCP port 25) Transfers mail messages and attachments. Wikipedia
Simple Mail Transfer Protocol Secure (SMTPS) port 465 Wikipedia
Simple Network Management Protocol (SNMP) Service uses port 161, trap uses port 162. Uses SNMP managers, agents, and MIBs. Consumes more bandwidth than Syslog. First defined in RFC 1067 August 1988. Wikipedia RFC 1067 Cisco (Configuring SNMP) Netacad CCIE or Null!
Simple Network Management Protocol version 1 (SNMPv1) Community-based form of security. Able to access an agent's MIB as defined by ACLs and passwords. Offer minimal security features. (No encryption or authentication.) Defined in RFC 1157 May 1990. Wikipedia RFC 1157
Simple Network Management Protocol version 2c (SNMPvc2) Community-based form of security. Able to access an agent's MIB as defined by ACLs and passwords. Offer minimal security features. (No encryption or authentication.) Wikipedia
Simple Network Management Protocol version 3 (SNMPv3) Authenticates and encrypts packets between management devices. Defined in RFC 5590 June 2009. Wikipedia RFC 5590
Simple Object Access Protocol (SOAP) Messaging protocol specification for exchanging structured information in the implementation of web services in computer networks. Allows developers to invoke processes running on disparate operating systems (such as Windows, macOS, and Linux) to authenticate, authorize, and communicate using Extensible Markup Language (XML). Since Web protocols like HTTP are installed and running on all operating systems, SOAP allows clients to invoke web services and receive responses independent of language and platforms. Wikipedia
Simple Service Discovery Protocol (SSDP) October 28, 1999 Wikipedia IETF
Simultaneous Peripheral Operations On-line (SPOOL) A buffer, typically for printers. Wikipedia
sine wave The most common AC waveform. 360° in each cycle. Voltage at any point along the waveform is equal to the peak (max) value × the sine of the angles of rotation. The average value is used when an AC sine wave is changed to DC. Wikipedia
single area OSPF Uses area 0. Good for small campus. Has a large routing table because summarization is disabled by default. LSDB. Frequent SPF algorithm calculations.
Single Data Rate Synchronous DRAM (SDR SDRAM) Wikipedia
Single Page Application (SPA) Web application or web site that fits on a single web page with the goal of providing a more fluid user experience similar to a desktop application. Wikipedia
Single Point Of Failure (SPOF) Where there is no redundancy. If the device fails, the rest of the system is affected. Wikipedia
Single Root Input/Output Virtualization (SR-IOV) Network interface that allows the isolation of the PCI Express resources for manageability and performance reasons. Wikipedia
Single UNIX Specification (SUS) Standards required to qualify as "UNIX" Wikipedia
Single-board computer (SBC) All parts of a computer are on a single board. The Raspberry Pi is an example SBC. Wikipedia
Single-Mode Fiber (SMF) Commonly used as backbone cabling or cable in phone systems. Light travels straight down the fiber and does not bounce off the fiber walls. Can transmit 10Gbps up to 40 kilometers (25.85 miles). Wikipedia
Single-Serving Sites (SSS) A website that consists if a single page and has a single isitchristmas.com
site Physical collection of Active Directory (AD) objects defined by subnet. Wikipedia
site-to-site VPN An extension of a WAN. Connects entire networks together. Both ends of the connection know about the VPN in advance, but internal hosts are not aware of the tunnel. VPN gateway encapsulates and encrypts. Wikipedia
SkyDrive Microsoft's online file storage, now renamed to OneDrive. (see OneDrive)
Skylake Microarchitecture codename from Intel. Announced August 5, 2015. Wikipedia
Skype A free softphone that uses proprietary protocols. First released August 29, 2003. Website Wikipedia
slope m The steepness of a line. Wikipedia
SMB 2.0 (aka: SMB2) Introduced with Windows Vista in 2007. Wikipedia
SIGGRAPH 2018 August 12-16 in Vancouver. Website
Small and Medium-sized Businesses (SMB)
Small and Medium-sized Enterprise (SME)
Small Computer System Interface (SCSI) Wikipedia
Small Form Factor (SFF) Desktop computers with a small footprint. The Mac Mini is a good example of a SFF computer. Wikipedia
Small Form Factor 8639 (SFF-8639) Website Wikipedia
Small Form-factor Pluggable (SFP) Wikipedia
Small Office/Home Office (SOHO)
Small Outline Dual In-line Memory Module (SO-DIMM) (aka: SODIMM) Memory form factor roughly half the size of regular DIMMs. Often used in laptops, Mini-ITX motherboards, and office printers. All 64-bit modules have a single keying notch.
| 72-pin SO-DIMM | older 32-bit |
| 100-pin SO-DIMM | older 32-bit, two notches |
| 144-pin SO-DIMM | single notch near the center |
| 200-pin SO-DIMM | (DDR/DDR2) single notch nearer to one side |
| 204-pin SO-DIMM | (DDR3) single notch closer to the center than on 200-pin SO-DIMMs |
| 260-pin SO-DIMM | (DDR4) 69.6 mm (2.74 inches) wide and 30 mm (1.2 inches) high, making them 2 mm (0.079 inches) wider than DDR3 SO-DIMMs, with a single notch after pin 144 |
| 260-pin SO-DIMM | (UniDIMM), 69.6 mm (2.74 inches) wide and 30 mm (1.2 inches) or 20 mm (0.79 inches) high, with a single notch placed differently than on DDR3 SO-DIMMs |
SmallBasic Programming language and IDE developed by Microsoft. Announced in October 2008 and released on July 12, 2011. Wikipedia Website TechNet Microsoft Blog
Smalltalk Object oriented programming language. Wikipedia
Smart Jack Type of Network Interface Device (NID) that includes circuitry to perform such functions as converting between framing formats on a digital circuit (T1), remote diagnostics, and regenerating a digital signal.
Smartsheet Management and collaboration Software as a Service (SaaS) Website Wikipedia
SMB 3.0 (previously named SMB 2.2) Introduced with Windows 8 and Windows Server 2012. Wikipedia
SMB 3.0.2 Allowed SMB1 to be optionally disabled for increased security. Introduced with Windows 8.1 and Windows Server 2012 R2. Wikipedia
SMB 3.1.1 Introduced with Windows 10 and Windows Server 2016. Wikipedia
SMB1 (deprecated, aka: Common Internet File System (CIFS)) Wikipedia
smurf attack Type DDoS attack where large amounts of ICMP packets are sent from a spoofed IP address on the network to the network broadcast address causing many replies. Originally written as smurf.c by Dan Moschuk, aka TFreak, in 1997. Wikipedia Hackepedia
snapshot Quick point-in-time backup of critical virtual machine files used to restore the VM back to that point. Wikipedia
SNMP agent Software that runs on a managed device such as a server, router, or switch.
SNMP manager (aka: Network Management System (NMS)) Runs a network management application.
Snow Leopard (Mac OS X 10.6) Wikipedia
Snow White and the Seven Dwarfs Frist full-length animated feature film. Produced by Walt Disney. Released December 21, 1937. Wikipedia
socket The combination of the source and destination IP addresses and the source and destination port numbers. Wikipedia
Socket AM3 (941 pins) CPU socket for AMD processors. Supports DDR3 memory. Compatible with AM3 and AM3+ processors including Phenom II, Athlon II, Sempron, Opteron 138x. Released February 9, 2009 as the successor to Socket AM2+. Wikipedia
Socket AM3+ (942 pins) Modification of the AM3 Socket for CPUs based on the AMD Bulldozer microarchitecture. Retains compatibility with AM3. Also supports the Piledriver microarchitecture including the FX line and Opteron 3000 series. Wikipedia
Socket FM1 (PGA-ZIF, 905 pins) CPU socket used by AMD Llano processors such as early A-series APUs and Athlon II. Released July 2011. Succeeded by Socket FM2. Wikipedia
Socket FM2 (PGA-ZIF, 904 pins) CPU socket used by AMD Trinity and Richland APUs as well as Athlon X2 and Athlon X4. Released September 27, 2012. Wikipedia
Socket FM2+ (PGA-ZIF, 906 pins, aka: FM2b) CPU socket used by AMD Steamroller microarchitecture Kaveri and Godavari APUs. Supports Socket FM2 CPUs. Released January 2014. Wikipedia
socket pair the source and destination IP addresses and port numbers Wikipedia
socket.gethostname() Prints the hostname in python. import socket Python Documentation
socket.gethostname()
SoftEther VPN (Software Ethernet) First released January 4, 2014. Website Wikipedia
softphone A phone that is not a phone. Wikipedia
software Set of instructions that control a computer. Wikipedia
Software as a Service (SaaS) (aka: cloudware) Software that is delivered form the web or "cloud". Gives access to applications through a subscription. Microsoft Office 356, Dropbox, and Google Docs are all examples of SaaS. Wikipedia
Software framework Wikipedia
Software-Defined Networking (SDN) Began shortly after Sun Microsystems released Java in 1995. Wikipedia
Software-Optimized Encryption Algorithm (SEAL) Alternative algorithm to software-based DES, 3DES, and AES. Stream cipher with 160 bit encryption key. Low CPU usage. Symmetric Developed in 1993 by Phillip Rogaway and Don Coppersmith. Netacad
SOH CAH TOA sin = Opposite/Hypotenuse, cos = Adjacent/Hypotenuse, tan = Opposite/Adjacent Khan Academy
solid figure A figure that lies in space.
Solid State Drive (SSD) A storage media that uses flash memory and allows data to be accessed faster than a standard HDD. Wikipedia
SolidWorks CAD/CDE sofware. Website Wikipedia
Sony Electronics manufacturer based in Tokyo, Japan. Founded May 7, 1946. Wikipedia
Sony Vaio 505 First released July 24, 1998. Wikipedia
Sony Xperia XZ Premium
| Display: |
|
| CPU: | Snapdragon 835 |
| GPU: | Adreno 540 |
| Memory: | 4 GB LPDDR4X RAM |
| Storage: |
|
| Camera: |
|
| Battery: | 3230 mAh |
| Dimensions: | H: 156 mm (6.1 in) W: 77 mm (3.0 in) D: 7.9 mm (0.31 in) |
| Weight: | 195 g |
| Ports: | USB 3.1 Gen 1 Type-C |
| MSRP: | $599.99 |
Sony Xperia XZ2 Smartphone from Sony. Announced February 25, 2018 at Mobile World Congress (MWC) 2018. Website
SORT Command that sorts input.
Sort-Object Used to sort objects in PowerShell. TechNet
source IP address Contains a 32-bit binary value that represents the source IP address of the packet.
source MAC address Part of an Ethernet frame.
source port The original protocol port that was used in in a data transfer.
Southbridge Wikipedia
Space Exploration Technologies Corporation (SpaceX) Founded May 2002. Website Wikipedia
Spacewar! First game on the PDP-1 Released in 1962. Wikipedia
spaghetti code Code having a complex and tangled control structure. Usually involving many GOTO statements. Wikipedia
Spanning Tree Algorithm (STA) Determines the best paths to the root bridge in the broadcast domain.
Spanning Tree PortFast BPDU Guard Enhancement (aka: BPDU Guard) Feature of the STP enhancement from Cisco that bypasses the spanning tree listening and learning process to speed up network convergence. Cisco
Spanning Tree Protocol (STP) 802.1D A legacy standard that runs all VLANs in a spanning tree instance. Developed to addresses the issue of routing loops. Ensures redundant physical links are loop-free. First standardized by IEEE as 802.1D in 1990. Original algorithm developed by Radia Perlman in 1985. Cisco Wikipedia Cisco (Understanding and Configuring Spanning Tree Protocol)
Spanning Tree Protocol Root Guard Enhancement (aka: root guard) Feature of the STP enhancement from Cisco that lets you administratively pick which bridge should be the root bridge. This works even if another switch is configured with a root priority of 0 and has a lower MAC address. Cisco
spanning-tree cost
syntax: spanning-tree cost (value 1-200,000,000) |
SPDY Wikipedia
Special Interest Group on Computer GRAPHics and Interactive Techniques (SIGGRAPH) Annual conference on computer graphics (CG) convened by the ACM SIGGRAPH organization. First held in 1974. Website Wikipedia
Spectre Breaks the isolation between different applications allowing an attacker to trick error-free programs. Reported January 3, 2018. Website Project Zero Blog ZDNet The Verge (Processor flaw exposes 20 years of devices to new attack)
Sperry Wikipedia
Sperry Rand Sperry renamed itself Sperry Rand after merging with Remington Rand. Wikipedia
SPF Tree Created by the SPF algorithm. Used to calculate the best path to each node.
SpiderMonkey JavaScript engine Wikipedia
split Split can separate files while cat can merge files. YouTube
Split Horizon Prevents routing loops in distance vector routing protocols. Does not allow advertisement updates to be sent back down the interface it was learned. Can cause problems for frame relay. Wikipedia
spoofing Masquerading as another entity, usually by spoofing an IP address, MAC address, or user.
spool A buffer, typically for printers.
Spotify An internet music streaming service. Website
SQL commands Can be divided into two overall categories: data definition language (DDL) and data manipulation language (DML) commands.
SQL injection Inserting lines of SQL code into a query, typically on a web site, with malicious intent such as to delete a database or to reveal its contents. Wikipedia
SQL Slammer Worm Worm that exploited a bug in Microsoft SQL Server and Desktop Engine. Launcehed January 25, 2003. Wikipedia
Squirrel GitHub
ssh -p (port number between 1025 and 65536) (username@server ip address) Linux SSH login.
SSH File Transfer Protocol (SFTP) (aka: Secure File Transfer Protocol) Secure file transfer protocol that uses SSH. Wikipedia
SSH forwarding Send another port over SSH.
Standard ACL Permit or deny traffic only from source Layer 3 (IPv4) addresses. Should be placed close to the destination.
standard input Comes from the keyboard by default. 0< (Shorthand: <)
standard library Library made available across implementations of a programming language. Wikipedia
standard output Goes to the display by default. 1> (Shorthand: >)
Standby Active Virtual Gateway (SVG) Takes over for the AVG if it goes down. Elected by next highest priority to the AVG.
Standby Virtual Forwarder (SVF) When more than 4 gateways are in a GLBP group then the rest will be SVF.
Star Wars Episode IV: A New Hope Released May 25, 1977.
Star Wars Episode V: The Empire Strikes Back Released May 17, 1980. Wikipedia
Star Wars Episode VI: Return of the Jedi Released May 25, 1983.
StarCraft Released March 31, 1998. Website Wikipedia
START Starts a separate window to run a specified program or command.
Start of Authority (SOA) Type of DNS record. Wikipedia
Start-Process powershell -Verb runAs Start PowerShell as Administrator. StackOverflow
startup configuration file Configuration file on network devices that is stored in NVRAM by default and accessed at startup.
stateful firewall Filters traffic based on what is allowed to enter or exit an interface, without inspecting the traffic. Only packets matching a known active connection are allowed to pass the firewall. Monitors state of connection through SPI. Most common type of firewall. Developed by Bell Labs in 1989. Wikipedia
Stateful Packet Inspection (SPI) (aka: dynamic packet filtering) Wikipedia
stateful protocol Protocol that keeps track of the state of the communication session.
Stateless Address Auto-Configuration (SLAAC) Method that allows a device to obtain an IPv6 prefix, prefix length, and default gateway address information from an IPv6 router without the use of a DHCPv6 server. Wikipedia
stateless application Application where data does not change. TechTarget
stateless firewall Blocking is based on Access Control Lists (ACLs) and defined rules. Can block and unblock by difined IP address, port access, or URL address.
statement Wikipedia
Static Application Security Testing (SAST) set of technologies designed to analyze application source code, byte code and binaries for coding and design conditions that are indicative of security vulnerabilities. SAST solutions analyze an application from the “inside out” in a nonrunning state, prior to going into production. Gartner
static NAT (aka: one-to-one) Statically configure the mapping of an inside local address (IP of internal server) to an inside global address (IP of server according to the internet). Wikipedia Juniper Cisco
Static Random-Access Memory (SRAM) (aka: Static RAM) Typically used as CPU cache memory. Faster than DRAM but more expensive and less dense. Does not need to be refreshed often. Type of semiconductor memory that uses bistable latching circuitry (flip-flop) to store each bit. Wikipedia Netacad
static route Used to connect a specific network or to provide a Gateway of Last Resort. Have an AD of 1. They can be configured with the next-hop IP address (recursive static route), an exit interface (directly connected static route), or both an IP and exit interface (fully specified static route). Static routes are easy to implement in small networks. More secure and efficient than dynamic routes. Routes will always be the same and need to be changed manually as the topology grows/changes. To configure a static route use the syntax:
ip route [destination ip address] [subnet mask] [ exit interface | next-hop ip address ]
Statistical Time-Division Multiplexing (STDM) Uses a variable time slot where data can compete for a free slot. Developed to overcome TDM inefficiency. Wikipedia
Steam A gaming social network. First released September 12, 2003. Wikipedia
Steam Machine (aka: Steam Box) Game console from Valve. Released November 10, 2015. Wikipedia
SteamOS Initially released December 13, 2013. Wikipedia
Steamroller Microarchitecture from AMD
steganography hiding data in plain view in pictures, graphics, or text. Wikipedia
step-down transformer Lower secondary voltage than primary voltage. Wikipedia
step-up transformer Higher secondary voltage than primary voltage. Wikipedia
Steve Jobs Co-founder of Apple with Steve Wozniak. February 24, 1955 - October 5, 2011 Wikipedia
Steve Wozniak Co-founder of Apple with Steve Jobs. Wikipedia
Stock Keeping Unit (SKU) Wikipedia
Stop-Process Introduced with PowerShell version 1.0. TechNet
Storage Area Network (SAN) Wikipedia
storage medium Where data can be stored. (Hard Drive, Blue-Ray Disc, paper, Wikipedia
Straight Through Cable (T-568A or T-568B to itself) Most common networking cable. Connect from a host network interface controller (a computer or similar device) to a network switch, hub or router. Wikipedia LINFO
Straight Tip (ST) (aka: stab and twist) Fiber-optic connector that uses a BNC attachment mechanism. Wikipedia
stream cipher Symmetric key cipher where plaintext digits are combined with a pseudorandom cipher digit stream (keystream). Wikipedia
Stream Control Transmission Protocol (SCTP) Transport layer protocol similar to TCP and UDP. Standardized by IETF in RFC 4960 September 2007. RFC 4960 Wikipedia
string Sequence of characters. Wikipedia
striping Writes segments of data across multiple drives. Wikipedia Netacad
Structured programming Wikipedia
Structured Query Language (SQL) Special programming language made for databases. Not case sensitive but best practice is to write commands in all-caps. Wikipedia W3Schools Khan Academy
stub network Router that is connected to a single router. Wikipedia
stutter calls itself twice. Wikipedia
Stuxnet Worm that targets PLCs. Discovered in June 2010. Wikipedia
sub HTML tag for subscript text. W3Schools
Submarine Telegraph Company Ran the first telegraph cable between England and France. Operaional November 13, 1850. Wikipedia HistoryofInformation.com This day in Tech History
subnet Physical segment in a Active Directory TCP/IP network. Website Wikipedia
subnet ID Part of an IPv6 global unicast address. Organizations use this to identify subnets within a site. Wikipedia
subnet mask (netmask) Logicaly subdivides a network. Identifies what part of an address is the network portion and what is the host portion. Wikipedia
subnet zero The first subnet obtained after subnetting the network address. Wikipedia Cisco
subnetwork (subnet) Logical subdivision of an IP network into two or more smaller networks. Wikipedia
subquery Query linked to another query. Wikipedia
Subscriber Connector (SC) (aka: square connector) Latched fiber-optic connector. Works with either SMF or MMF. Not as popular as ST connectors for LAN connections. Wikipedia
Subscriber Identity Module (SIM) (aka: sim card) Developed in 1991 by Munich smart-card maker Giesecke & Devrien. Wikipedia
SUBST DOS command that associates a path with a drive letter.
substitute user (su) Execute a command as another user.
Substitution (Caesar cipher) Shifts the alphabet. Retains letter frequency.
sudo Website
suite Collection of software sold as a package. i.e.: Microsoft Office
summary route Can help minimize the number of static routes in the routing table. IPv6 addresses can be summarized into a static route if: 1) the destination networks are contiguous and 2) the static routes all use the same exit interface or next-hop IPv6 address. Wikipedia
Sun Microsystems Bought by Oracle in 2009. RIP :( Wikipedia
sup HTML tag for superscript. W3Schools
Super Mario Run Mobile game made by Nintendo. Released December 15 2016. Wikipedia
Super Nintendo Entertainment System (SNES) (aka: Super Nintendo) Video game console made by Nintendo. First released in Japan November 21, 1990. Wikipedia
super-server Type of daemon on UNIX. Wikipedia
supercomputer Many processors connected together (either distributed or cluster) to solve complex problems. First designed by Seymour Cray in the 1960's Wikipedia
supernet route A routing table entry with a subnet mask less than the classful mask. (summary address) Wikipedia
supervisor password Restricts access to the BIOS setup utility.
Supervisory Control and Data Acquisition (SCADA) Used to manage Heating, Ventilation, and Air-Conditioning (HVAC) and other types of industrial and environmental systems. Wikipedia
Surface Book 2 Laptop from Microsoft. Announced October 17, 2017. Available for pre-order beginning November 9, 2017. Shipping November 16, 2017. Website Wikipedia Windows Blogs
swap (aka: virtual memory) Minimum recommended size of 256 MB. Wikipedia Red Hat Ubuntu Help
Swift Programming language developed by Apple. Announced June 2, 2014. Wikipedia Website
switch Network device that typically operates at OSI Layer 2, Layer 3, or Layer 7. Provides centralized connectivity similar to hubs. Forwards data only to the device(s) that need to receive it based on the Layer 2 header. Filters MAC addresses and builds a MAC table. Switch has ports, router has interfaces. Can operate with or without VLANs. First Ethernet switch was introduced by Kalpana in 1990. Wikipedia Network Computing archive
Switch Virtual Interface (SVI) logical interface associated with a VLAN. Can allow for remote switch administration. Used to assign an IP addresses to a Layer 2 switch where no physical interface for IP is available.
Switched Port Analyzer (SPAN) Copies packets to another port on the switch to analyze.
Switched Virtual Circuit (SVC) Established dynamically by sending signaling messages to the network (CALL SETUP, DATA TRANSFER, IDLE, CALL TERMINATION). Netacad
Symmetric Block Ciphers Encrypts in blocks, typically 64 bits for DES or 128 bits for AES. RSA has a variable block size. Output may be larger than the input to match the block size. Netacad
Symmetric DSL (SDSL) Wikipedia
symmetric encryption algorithm (secret keys) Uses a single key to encrypt and decrypt data. 80-256 bits. Most common because of shorter key length. Uses block ciphers and stream ciphers. (DES, 3DES, AES, IDEA, RC2/4/5/6, and Blowfish) Wikipedia
Symmetric Stream Ciphers Encrypts one bit at a time. Technically a block cipher with a bit size of one bit. Faster than block ciphers and generally don't increase message size. Examples include The Vigen Netacad
SYN/ACK Packet sent in response to a SYN packet. Wikipedia
Synchronous Code-Division Multiple Access (S-CDMA)
Synchronous Data Link Control (SDLC) Layer 2 protocol. Wikipedia
Synchronous Digital Hierarchy (SDH) European-based ETSI and ITU standard. Uses optical (fiber) to transmit data over a WAN connection. Wikipedia
Synchronous dynamic RAM (SDRAM) Wikipedia
Synchronous Optical Networking (SONET) ANSI standard. Uses optical (fiber) to transmit data over a WAN connection. (155.52Mbps) Wikipedia
syntax Proper "grammar" for code. The correct arrangement for a command or line of code.
SYS Wikipedia
syslog (UDP port 514) Standard for a separate central log server on UNIX-like systems. Levels include:
| 0 | Emergency | Most severe error condition, which render the system unusable |
| 1 | Alert | Requires immediate attention |
| 2 | Critical | Less-severe condition. Should be addressed to prevent service interruption. |
| 3 | Error | Error condition with the system that do not render the system unusable. |
| 4 | Warning | Notification that specific operations failed to complete successfully. |
| 5 | Notification | Non-error notification that alerts an administrator of state changes. |
| 6 | Informational | Detailed information about the normal operation of a system. |
| 7 | Debugging | Highly detailed information (i.e. info on individual packets) typically used for troubleshooting. |
syslog facility level Default is local7
System Call Interface (SCI) API for the Linux kernel. Wikipedia
System Configuration (MSConfig) Tool that can help identify problems that might prevent Windows from starting correctly. Wikipedia Microsoft
System Development Life Cycle (SDLC) Five phases: initiation, acquisition and development, implementation, operations and maintenance, and disposition. Netacad
System LifeCycle (SLC) The system lifecycle (SLC) should provide valuable guidance on the best practices that need to be followed throughout the network.
System Management Basic Input/Output System (SMBIOS) (System Management BIOS) Introduced in 1999. Wikipedia
System Management Controller (SMC)
system of equations Set of 2 or more equations.
system of linear equations (aka: linear system) Collection of two or more linear equations involving the same set of variables. Wikipedia
System on a Chip (SoC) (aka: System on Chip) An integrated circuit with all components of a computer. Wikipedia
System Preparation Tool (Sysprep) Tool from Microsoft used for Windows deployment. Can modify an image before committing the final clone. TechNet Wikipedia Netacad
System Shock Released September 23, 1994. Wikipedia
System Shock 2 First released August 11, 1999. Wikipedia
Système International (SI) (aka: International System of Units or metric system) Wikipedia
systeminfo Command that displays the system information of a Windows based system.
Systems Network Architecture (SNA) IBM's proprietary networking architecture. Created September, 1974. Wikipedia