(adj.) of a communication system. Polling involves a node inspecting the communication hardware - typically a flag bit - to see if information has arrived or departed. Polling is an alternative to an interrupt driven system. The natural synchronization of the nodes imposed by polling is used in the implementation of blocking communications primitives.
A means of controlling devices on multi-point line. Usually utilized to send/receive information via modem from remote computers to a central computer.
Technique used to determine when a device requires attention, by having the processor continuously test the device's status. See Interrupt.
Process by which a computer checks the readiness of other units to transmit or receive signals and information.
A means of controlling communications lines. When many stations are connected to the same circuit, polling from the center is used to ensure an orderly flow of data to the central location. Polling is an alternative to contention that ensures that no terminal is kept waiting for a long time.
A channel access method (CAM) protocol where a request for data is made. In a master/slave scenario, the master queries each slave device in turn as to whether it has any data to transmit. If the slave answers yes then the device is permitted to transmit its data. If the slave answers no then the master moves on and polls the next slave device. The process is repeated continuously. For Tivoli Access Manager, the WebSEAL server can be configured to regularly poll the master authorization (policy) database for update information.
The process by which a computer periodically asks each terminal or device on a LAN if it has a message to send, and then allows each to send data in turn. One multiport connection or a point-to-point connection, polling is the process whereby data stations are invited one at a time to transmit.
Polling is a routine that is constantly being performed by your computer. It checks each device individually to see if there is any new information or if the device is ready to send or receive data.
Usually refers to some form of data network arrangement whereby a central computer asks each remote location in turn (and very quickly) whether they want to send some information. The purpose is to give each user or each remote data terminal an opportunity to transmit and receive information on a circuit or using facilities which are being shared. Polling is typically used on a multipoint or multidrop line. Polling is done to save money on telephone lines.
A process in which a network management station sends periodic queries to software agents residing in network devices to gather information about network traffic flow. This method of controlling the sequence of data transmission by devices on a multipoint line requires each device to wait until the controlling processor requests it to transmit.
An access method with which a hub asks each node in turn if it has data to transmit.
A method where a computer sends a signal to a plotter or printer requesting information on the current production area. The device sends back an answer on production parameters; the production software then sets panels, or tiles, based on information. Works only with serial communications.
Access method in which a primary network device inquires, in an orderly fashion, whether secondaries have data to transmit. The inquiry occurs in the form of a message to each secondary that gives the secondary the right to transmit.
A line-control procedure in which each terminal is "polled" in rotation to determine whether a message is ready to be sent.
A communications technique that determines when a terminal is ready to send data. The computer continually interrogates its connected terminals in a round robin sequence. If a terminal has data to send, it sends back an acknowledgement and the transmission begins. Contrast with interrupt-driven, in which the terminal generates a signal when it has data to send.
A technique a CPU can use to learn if a peripheral device is ready to receive data or to send data. In this method each device is checked or polled in-turn to determine if that device needs service. The device must wait until it is polled in order to send or receive data. This method is useful if the device's data can wait for a period of time before being processed, since each device must await its turn in the polling scheme before it will be serviced by the processor. Contrast with interrupt.
A process by which the CPU checks the status of connected devices to determine if they are ready to send or receive data.
The process of periodically querying a device so the system can elicit the device's state (availability) or some other information.
A protocol in which a host or master station 'polls' each remote station in turn for incoming data. The remotes may only respond when polled.
A process in which a device polls the terminals connected to it, asking whether or not they have data to be sent to the host.
a process in which the status of devices attached to a bus system is periodically sampled.
The process by which databases are interrogated at regular intervals to determine if data needs to be transmitted.
The method used for terminal to controller communications. The controller systematically asks for each terminal if it needs to transmit to the controller.
A network arrangement whereby a central computer asks each remote location whether it wants to send information. This arrangement enables each user or remote data terminal to transmit and receive information on shared facilities.
Polling is the process in which a number of peripheral devices, remote stations, or nodes within a plant-based or SCADA network are accessed by a client application via a server to read and write data.
Systematic querying of devices to determine operational status, to avoid contention, or to determine readiness to send or receive data.
Method of controlling terminals on a multi-point line by which a computer acting as master calls or polls each of the terminals in turn to find out if they have any data to send. This access method is used in star topology networks but is generally being superseded by the preferred interrupt method.
A control message sent from a master terminal to a slave terminal as an invitation for the slave to transmit.
Interrogation of devices for purposes such as to avoid contention, to determine operational status, or to determine readiness to send or receive data.
The collection of data stored in a terminal by a central computer or polling service
User-initiated request to get status information from devices.
Polling is the fax mode of operation where the caller requests the remote answering machine to send a fax.
A communications control method used by some computer/terminal systems whereby a "master" station asks many devices attached to a common transmission medium, in turn, whether they have information to send.
When the CPU checks a device to determine if they are ready to send and receive data.
Communications access control procedure where a primary (master) station systematically invites secondary stations, one at a time, to transmit data.
Making continuous requests for data from another device. For example, modems that support polling can call another system and request data.
The facility whereby an operational centre sends an instruction (a polling command) to selected MESs to perform a defined task, such as returning a pre-assigned data report or performing a SCADA operation.
A host-system–controlled method for determining whether each of the stations on a communication line has data to send.
The act of a computer (or controller) asking end devices if they have information to send to the computer (or controller.)
(Wireless) An interrogation sequence used by communication devices to determine health status and/or integrity of an RF link established with another device in the network.
An inquiry from the CPU, central hub, or controller asking for a specific set of data (for example, statistics) from a device, device subsystem, or application (such as a specific protocol or interface).
Polling, in computer science, refers to actively sampling the status of an external device by a client program as a synchronous activity. Polling is most often used in terms of I/O, and is also referred to as polled I/O.