Asynchronous communication
In computer science and network technology , asynchronous communication is understood to be a mode of communication in which the sending and receiving of data takes place at different times and without blocking the process, for example by waiting for the recipient's response (as is the case with synchronous communication ).
Asynchronous communication is not to be confused with the term asynchronous data transmission ; this relates to media access procedures .
Examples of asynchronous communication between people are
- Email and SMS conversations,
- Newsletters or mailing lists as well
- Entries in discussion forums or newsgroups .
Many groupware systems have proprietary services for sending and receiving messages.
implementation
Polling
Select (/ poll) loops
The Syscall select can be used under Unix and BSD operating systems, which halts a process until a resource has become accessible. Some Unix derivatives offer better scaling functions, such as B. epoll on Linux, kqueue on FreeBSD , and / dev / poll on Solaris .
Callback functions
Available on Mac OS , VMS and Windows
Easy processes
Light-weight processes (LWPs) originally come from Plan 9
Channel I / O
Available on mainframes where the coprocessor handles the interrupts
Registered I / O
Available on Windows Server 2012 and Windows 8
literature
- Peter Mandl, Andreas Bakomenko, Johannes Weiss: Basic course in data communication. 2nd edition, Vieweg + Teubner Verlag, Wiesbaden 2010, ISBN 978-3-8348-0810-3 .
- Klaus Beck: Computer-mediated communication on the Internet. R. Oldenbourg Verlag, Munich 2006, ISBN 978-3-486-57891-1 .
- Martina Dittler: Computer-mediated communication in network-based learning scenarios. Herbert Utz Verlag, Munich 2002, ISBN 3-8316-0131-3 .
- Gernot Starke: Effective software architectures. 7th revised edition, Carl Hanser Verlag, Munich 2015, ISBN 978-3-446-44361-7 .
- Ralf Reichwald (ed.): Mobile communication. 1st edition, Verlag Th. Gabler, Wiesbaden 2002, ISBN 978-3-409-11865-1 .
See also
Web links
- Why the phone call disappears
- Asynchronous I / O support in Linux 2.5
- Middleware Concepts (accessed August 7, 2017)
- Distributed Systems Communication Models (accessed August 7, 2017)
- Coupled (synchronous) or uncoupled (asynchronous) communication and simple or complex messaging functions in connection with an enterprise service bus. (accessed on August 7, 2017)