This glossary was written and prepared by Blair Bergum of  DNSnews.net
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SAN

Storage Area Networks. Specialty high-speed storage technology. SANS are typically designed for 100GB-100TB of storage. It is primarily used for extremely large database applications. It is not to be used for shared read/writes. SANS are ultra-high performance storage systems with very high data reliability.

SAS 70

Statement on Auditing Standards, No. 70, (Service Organizations), is an auditing standard developed by the AICPA. See also SAS 70, Level I, and SAS 70, Level II.

SAS 70 Level I

Statement on Auditing Standards, No. 70, (Service Organizations), Level I, is a type I report which gives a description of the service organization's controls at a specific point in time. See also SAS 70, and SAS 70 Level II.

SAS 70 Level II

Statement on Auditing Standards, No. 70, (Service Organizations), Level II, is a type II report which describes the service organization's controls over at least a six month period. See also SAS 70, and SAS 70, Level I.

script

a small program that dynamically alters a webpage.

Secondary Master Name Server

Secondary Master Name Server, receives its zone data from another name server that is authoritative for the zone, namely from a Primary Master Name Server.

SEI

Software Engineering Institute, a non-academic unit of CMU. The SEI is a FFRDC and is operated by CMU. The SEI oversees the NSS which manages the CERT/CC.

Sending Prodigous Amounts of Email

See SPAM.

serial no.

in identification number associated with every zone file, and is updated incrementally each time the zone file is modified.

SERK

Server Extensions Resource Kit, for the MS web publishing software FrontPage, is a resource kit of instructions for Internet Service Providers and Internet Web server administrators covering installation, administering, securing, and troubleshooting the FrontPage server extensions.

server

a computer that is attached to a network that contains files and applications and acts as a service provider to provide access of network resources to users over a network, by serving requests to clients that are attached to the network.

Server Side Includes

see SSI

service

a program or routine that performs a specific function to support other programs.

SET

Secure Electronic Transaction

SGML

Standard Generalized Markup Language, is a standard identifying how to markup a language or tag set of commands. HTML is a subset of SGML. SGML was named after its' founders, starting with the word Standard, and the developer's names, Golbfarb, Mosher, and Lorie. SGML was created as a proprietary file format for IBM. In 1986 it was made publically available and is governed by ISO standard 8879. SGML provided a methodolgy for organizing and tagging elements in a document. HTML is a subset of SGML.

SGML is composed of three parts

1) Declaration: specifies which characters and delimiters are legal in a document.

2) Document Type Definition (DTD): a list of rules a document must conform regarding the document structure.

3) Document Instance: the actual document that contains the hypertext markup language.

shared IP

See virtual IP.

shared server

describes a web server where there is a virtual sharing of resources as compared to a dedicated server.

shtml

the extension used to denote html files that incorporates SSI.

S-HTTP

Secure HTTP, is a secure protocol which uses encryption data, but does it one message at a time as compared to SSL which does it by establishing and entire secure encrypted connection. The browser will display https:// when it is activated. Also known as HTTPS.

skitter

a tool developed by CAIDA that uses ICMP echo requests to probe the Internet to analyze Internet topology and performance. Skitter measures the TTL (Time To Live) of each IP packet header during each hop and records this information until the destination host is reached.

SLA

Service Level Agreements are agreements between hosting companies and their service providers that guarantee a certain agreed upon performance standards such as uptime and packet transfer.

SLD

Second-Level-Domain is the name portion of a domain name that proceeds the TLD name portion. It is this portion of the domain name that a registrant registers to identify their domain name. EventsUpdate is the SLD portion of EventsUpdate.com.

slave server

is a secondary Name Server.

slave record

is a secondary master resource record that gets its information from another name server, as opposed to the host server itself, which would be the primary master name server, whose resource record would be authoritative.

SLED

Single Large Expensive Disk, is a used to define the method of utilizing a single disk for your server or database needs, rather than using multiple less expensive disks, as in RAID.

SLIP

Serial Line Interface Protocol sends packets down a serial link that is delimited with special END characters.

SNMP

Simple Network Management Protocol is a TCP/IP protocol that defines information for managing TCP/IP based devices.

smart radio

is another term for Radio Data System (RDS) where a radio in the U.K. can tune to another station automatically to get a stronger signal if the stations are both broadcasting the same radio program. This is especially beneficial for travelers who are driving away from a station and the signal is getting weaker. See also RDS.

SMTP

Simple Mail Transfer Protocol is the standard for transmitting email across the Internet. Also known as the Out-going mail server, it facilitates email messages to be sent to other servers.

smtp.

an SMTP mail server, an alternate way to denote mail. to denote an SMTP mail server.

sponsored TLD’s

TLD’s that are restricted and have certain criteria that needs to be met for a registrant to register a domain name.

SOA

Start of Authority, is a resource record of a zone data file. It specifically is part of the RDATA.  The SOA indicates that a name server is the authority for the zone information in a given zone and marks the start of the DNS zone. There are seven fields that are required in the SOA record:

MNAME specifies the domain name of the zones primary master NS.

RNAME specifies the email address of the administrator zone.

serial number specifies the date and version in the format of YYYYMMDDVV.

refresh value specifies how frequently slave NS should check the master NS (for zone changes).

retry value specifies how frequently the slave NS should check the master NS after a serial number check has failed.

expire value specifies how long the zone’s NS will continue responding if they are unable to reach the primary master NS.

negative caching time to live value specifies how long NS can cache a negative result from a query.  A negative result means that the serial numbered version has changed.  It is the minimum TTL time after which a RR can be updated.

SPAM

Sending Prodigious Amounts of Email, a disparaging term to describe UCE, (Unsolicited Commercial E-mail), otherwise known as junk-mail.

spyware

software that tracks users' behavior with a user's knowledge. Many times spyware can be introduced into a user's computer via a Trojan Horse, or thru legitimate software applications, such as DoubleClick and RealNetworks which introduce spyware for other companies. See also adware.

SRI International

Under contract by DARPA to publish the Requests for Comments.

SRI

Stanford Research Institute, Their NIC was responsible for managing the initial host table prior to the implementation of the DNS.

SRI-NIC

Stanford Research Institute’s Network Information Center managed the original host table before the implementation of the DNS by Paul Mockapetris.

SRS

Shared Registration System, is a domain name registration system for competitive registars in the unsponsored gTLD’s.

SSH

Secure Shell Access is a UNIX based command interface and protocol for gaining secure access to a server remotely.

SSI

Server Side Includes, is a HTML directive to dynamically create content for webpages by dynamically inserting text files within an html file upon loading the web page. Servers that are not parsed, need to have files that utilize SSI labeled with the .shtml file extension rather than the .htm or .html extensions. The .shtml extension tells the web server that there is an SSI embedded into the HTML document.

SSL

Secure Sockets Layer is a protocol developed by Netscape for securely transmitting private documents over the Internet, by using encryption technology with a private key. SSL is used in conjunction with HTTPS.

SSP

Storage Service Provider, a provider who manages a client's storage needs with SANS, primarily for large Fortune 500 companies with very large database application needs.

Standard Generalized Markup Language

See SGML.

Standard Golbfarb Mosher Lorie

See SGML.

static IP

an IP address that is permanently assigned to a server or web space on a server to aid in the immediate resolving of a client request to point to a particular domain.

sTLD

sponsored TLD, is a TLD that has restrictions for its’ members. It is not open to the general public. Also known as a rTLD, (restricted TLD).

STM

see Stream Multiplexers.

STM-4

Stream Multiplexer 4, transmits up to 6.22 Mbps. See also Stream Multiplexer.

STM-16

Streaming Multiplexer 16, transmits up to 2.5 Gbps. See also Stream Multiplexor.

stream multiplexer

the term given when edge servers of a CDN split a single feed to receive streaming data content into multiple streams to deliver the content to the client faster. Also known as a STM.

stub domain

See LAN.

stub level

the third level of a network layer in hierarchical routing, in the Internet. See hierarchical routing. Also known as a transit level.

subdomains

additional domains that are created off of the second-level-domains that a registered domain name holder or registrant can create to segment their domain name space. A subdomain is also known a third-level- domain name.

suffix

the extension portion of a domain name, also known as the extension.

supernetting

See CIDR.

SWITCH

Switzerland and Liechtenstein, (Swiss Education and Research Network), has the delegated responsibility for domain name registration and assignment for the ccTLD’s of Switzerland (.ch) and of the Principality of Liechtenstein (.li).

syslog

a log file program or daemon, where name server configuration errors are logged when the name server reads the configuration file and zone data files and finds an error.