Browse Definitions:
Definition

stateless

Contributor(s): Mats Borger and Joseph Flanigan

Also see finite state machine .

Stateful and stateless are adjectives that describe whether a computer or computer program is designed to note and remember one or more preceding events in a given sequence of interactions with a user, another computer or program, a device, or other outside element. Stateful means the computer or program keeps track of the state of interaction, usually by setting values in a storage field designated for that purpose. Stateless means there is no record of previous interactions and each interaction request has to be handled based entirely on information that comes with it. Stateful and stateless are derived from the usage of state as a set of conditions at a moment in time. (Computers are inherently stateful in operation, so these terms are used in the context of a particular set of interactions, not of how computers work in general.)

The Internet's basic protocol, the Internet Protocol ( IP ), is an example of a stateless interaction. Each packet travels entirely on its own without reference to any other packet. When you request a Web page from a Web site, the request travels in one or more packets, each independent of the other as far as the Internet Protocol program itself is concerned. (The upper layer Transmission Control Protocol - TCP - does relate packets to each other, but uses the information within the packet rather than some external information to do this.) The term connectionless is also used to describe communication in which a connection is made and terminated for each message that is sent. IP is connectionless as well as stateless.

The Web's Hypertext Transfer Protocol ( HTTP ), an application layer above TCP/IP, is also stateless. Each request from a user for a Web page or URL results in the requested pages being served, but without the Web (HTTP) server remembering the request later. In other words, there is no recorded continuity. Each communication is discrete and unrelated to those that precede or follow. In order to have stateful communication, a site developer must furnish a special program that the server can call that can record and retrieve state information. Web browsers such as Netscape Explorer and Microsoft Internet Explorer provide an area in their subdirectories where state information can be stored and accessed. The area and the information that Web browsers and server applications put in this area is called a cookie .

In formal protocol specifications, a finite state machine is an abstract desciption of how a stateful system works that describes the action that follows each possible state.

The Internet (including the World Wide Web) can be thought of as a stateless system or machine. Most computers, human beings, and elephants are stateful.

This was last updated in April 2005

Join the conversation

1 comment

Send me notifications when other members comment.

By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Please create a username to comment.

Thanks, I'm new to this but you cleared this up for me
Cancel

-ADS BY GOOGLE

File Extensions and File Formats

Powered by:

SearchCompliance

SearchSecurity

  • password

    A password is an unspaced sequence of characters used to determine that a computer user requesting access to a computer system is...

  • adware

    Adware is any software application in which advertising banners are displayed while a program is running.

  • botnet

    A botnet is a collection of internet-connected devices, which may include PCs, servers, mobile devices and internet of things ...

SearchHealthIT

SearchDisasterRecovery

  • call tree

    A call tree -- sometimes referred to as a phone tree -- is a telecommunications chain for notifying specific individuals of an ...

  • mass notification system (MNS)

    A mass notification system is a platform that sends one-way messages to inform employees and the public of an emergency.

  • disaster recovery as a service (DRaaS)

    One approach to a strong disaster recovery plan is DRaaS, where companies offload data replication and restoration ...

SearchStorage

  • data migration

    Data migration is the process of transferring data between data storage systems, data formats or computer systems.

  • compact disc (CD)

    A compact disc is a portable storage medium that can be used for recording, storing and playing back audio, video and other data ...

  • secondary storage

    Secondary storage is used to protect inactive data written from a primary storage array to a nonvolatile tier of disk, flash or ...

SearchSolidStateStorage

  • SSD RAID (solid-state drive RAID)

    SSD RAID (solid-state drive RAID) is a methodology commonly used to protect data by distributing redundant data blocks across ...

  • Tier 0

    Tier 0 (tier zero) is a level of data storage that is faster, and perhaps more expensive, than any other level in the storage ...

  • PCIe SSD (PCIe solid-state drive)

    A PCIe SSD (PCIe solid-state drive) is a high-speed expansion card that attaches a computer to its peripherals.

SearchCloudStorage

  • RESTful API

    A RESTful application program interface breaks down a transaction to create a series of small modules, each of which addresses an...

  • cloud storage infrastructure

    Cloud storage infrastructure is the hardware and software framework that supports the computing requirements of a private or ...

  • Zadara VPSA and ZIOS

    Zadara Storage provides block, file or object storage with varying levels of compute and capacity through its ZIOS and VPSA ...

Close