Datagram

Datagram

A datagram is a basic transfer unit associated with a packet-switched network in which the delivery, arrival time, and order are not guaranteed. A datagram consists of header and data areas, where the header contains information sufficient for routing from the originating equipment to the destination without relying on prior exchanges between the equipment and the network. The source and destination addresses as well as a type field are found in the header of a datagram.

The term datagram is often considered synonymous to "packet", but there are some nuances. First, the term packet applies to any message formatted as a packet, while the term datagram is generally reserved for packets of an "unreliable" service. An "unreliable" service does not notify the user if delivery fails. For example, IP itself provides an unreliable service and UDP over IP also provides an unreliable one. That is why UDP packets are generally called datagrams.[1] Second, if a datagram fragments, then its fragments may be referred as packets, but not as datagrams. However, TCP refers to its fragments as TCP segments, not packets,[2] presumably to assert that its fragments are reliable.

See also

References

  1. ^ Kurose, James F. & Ross, Keith W. (2007), "Computer Networking: A Top-Down Approach" ISBN 0-321-49770-8
  2. ^ RFC 793

Wikimedia Foundation. 2010.

Игры ⚽ Поможем сделать НИР

Look at other dictionaries:

  • datagram — (izg. dèjtagram) m DEFINICIJA inform. paket podataka koji u sebi nosi dovoljno informacija za svoj prijenos do odredišta; datogram ETIMOLOGIJA engl …   Hrvatski jezični portal

  • datagram —    A message unit that contains source and destination address information, as well as the data itself, which is routed through a packet switching network. The data held in the datagram is often referred to as the payload, and the addressing… …   Dictionary of networking

  • datagram — duomenų paketas statusas T sritis informatika apibrėžtis Duomenų porcija, siunčiama tinklu kaip nedalomas vienetas. Paketą sudaro ↑duomenų paketo antraštė ir patys duomenys. atitikmenys: angl. datagram; packet ryšiai: dar žiūrėk – duomenų paketo… …   Enciklopedinis kompiuterijos žodynas

  • Datagram service — is a service provided by IP at the Internet layer. It is a connectionless, best effort, unreliable, message delivery service. Many higher level protocols including TCP (a connection oriented service) depend on IP s Datagram service, laying… …   Wikipedia

  • Datagram Transport Layer Security — Saltar a navegación, búsqueda Datagram Transport Layer Security (DTLS) es un protocolo que proporciona privacidad en las comunicaciones para protocolos de datagramas. Este protocolo permite a las aplicaciones cliente/servidor comunicarse de… …   Wikipedia Español

  • Datagram Delivery Protocol — (DDP) ist ein Begriff aus der Informatik. Das Datagram Delivery Protocol ist das Datenübertragungsprotokoll innerhalb von AppleTalk. Das DDP ist vergleichbar mit dem Internet Protocol (IP). Name Binding Protocol (NBP), Routing Table Maintenance… …   Deutsch Wikipedia

  • Datagram Delivery Protocol — (DDP) is a member of the AppleTalk networking protocol suite. Its main responsibility is for socket to socket delivery of datagrams over an AppleTalk network. Note: All application level protocols, including the infrastructure protocols NBP, RTMP …   Wikipedia

  • Datagram Congestion Control Protocol — Internet protocol suite Application layer BGP DHCP DNS FTP HTTP …   Wikipedia

  • Datagram Transport Layer Security — In information technology, the Datagram Transport Layer Security (DTLS) protocol provides communications privacy for datagram protocols. DTLS allows datagram based applications to communicate in a way that is designed to prevent eavesdropping,… …   Wikipedia

  • Datagram socket — A datagram socket is a type of connectionless Internet socket, which is the sending or receiving point for packet delivery services.[1] Each packet sent or received on a datagram socket is individually addressed and routed. Multiple packets sent… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”