A datagram is a basic transfer unit associated with a packet-switched network in which the delivery, arrival time, and order of arrival are not guaranteed by the network. In simpler terms, it’s a self-contained, independent entity of data carrying sufficient information to be routed from the source to the destination computer without reliance on earlier exchanges. This term is often used in internet protocols, like IP datagram in the IP protocol.


The phonetic transcription of the word “Datagram” is /ˈdeɪ.tə.ɡræm/.

Key Takeaways


  1. Datagram is a basic transfer unit associated with a packet-switched network in which the delivery, arrival time, and order of arrival are not guaranteed by the network system.
  2. Each datagram is independently routed, with no reference to packets that have gone before. This makes them suitable for open networks where some degree of packet loss is acceptable.
  3. Datagrams are used in Internet Protocol (IP) network level communications where they provide a connectionless communication service across a packet switched network.



The term “datagram” is important in technology, particularly in the field of computer networking, because it refers to a self-contained packet of data that carries information sufficient for it to be routed from its source to its destination without reliance on earlier exchanges. In simpler terms, a datagram can be seen as an independent entity — carrying not just data, but also information about its origin and destination. This unique feature ensures that even if a particular data packet gets lost or corrupted during transmission, it doesn’t halt or disrupt the overall communication process, making it a crucial element in ensuring the robustness and reliability of data networks. It is widely used in protocols in modern networks including the Internet Protocol.


Datagram technology plays a critical role in data communication across computer networks. It serves as the basic unit of data in packet-switched networks, enabling effective communication and data transmission over local area networks (LANs), wide area networks (WANs), and the internet. By use of packet-switching technology, datagrams hold self-contained packets of data that carry enough information to be routed and dispatched by a switch to their destination without reliance on earlier exchanges. This technology hugely contributes to enabling the complex, decentralized, and consistently varying network system we find on the internet today.The reason why datagrams are essential revolves mainly around their efficiency and reliability in transmitting data. Since each datagram operates independently, it can opt for differing paths to reach its destination. This, therefore, introduces flexibility and this mitigates the problem of data traffic congestion. Furthermore, this approach improves data transmission reliability because if one path fails, the datagram can be redirected through another path while not affecting the flow of other datagrams. Essentially, this independence of datagrams paves the way for more robust and adaptable data communication in different network conditions.


1. Internet Protocol (IP): The most common example of datagram usage is the Internet Protocol. In IP, the term “datagram” refers to the basic unit of data that is transferred across the internet. It contains the source and destination IP addresses, in addition to other metadata along with the data payload. Each of these IP datagrams can take different paths to reach the destination, allowing for more robust and flexible data transmission.2. User Datagram Protocol (UDP): This is often used in real-time systems and applications like live streaming, online games, and voice over IP (VoIP) where speed of data transmission is more crucial than ensuring that every single datagram reaches its destination. In these cases, any lost or dropped datagrams are acceptable to a degree because re-transmitting them might lead to delays that could negatively impact the real-time nature of the application.3. Ethernet Network: In an Ethernet network, each frame of data that is sent between computers is essentially a datagram. It includes information necessary to deliver the data to the correct destination, error-checking codes, and the actual payload data. The Ethernet protocol doesn’t care about the sequence of datagrams, it just sends or receives them independently, which reflects a key characteristic of the datagram service model.

Frequently Asked Questions(FAQ)

**Q1: What is a Datagram?**A: A datagram is a basic transfer unit associated with a packet-switched network. It is an independent, self-contained message sent over the network whose arrival, arrival time, and content are not guaranteed.**Q2: How does a Datagram work?**A: A datagram is sent from a source to a destination. Each datagram is transmitted separately and can follow different paths to its destination, where they may arrive in any order, even out of sequence. **Q3: What are some common uses of Datagrams?**A: Datagrams are commonly used in applications and higher layer protocols such as UDP (User Datagram Protocol) where time is a critical factor. They are also used in IP (Internet Protocol) to provide a model of transmitting packets.**Q4: How does Datagram differ from a Packet?**A: While both packets and datagrams are used in data transmission, they have a slight difference. Packets are used in connection-oriented networking models where a path is established before data transmission, while datagrams are used in connectionless networking models where each data is sent independently.**Q5: What does UDP (User Datagram Protocol) mean?**A: UDP is a part of the Internet Protocol suite used by programs running on different computers to send short messages. It uses the datagram concept, meaning that the delivery and the correct sequencing of the packages are not guaranteed. **Q6: What are the advantages of using Datagram?**A: The main advantage of using datagrams is their simplicity. They don’t need to establish a connection before data transmission, can be routed independently, and are suitable for real-time applications where speed is more critical than sequence or integrity.**Q7: What are the limitations of using Datagram?**A: The limitation of using datagrams comes from their unreliability: they offer no guarantees for delivery, and no protection against duplication. Furthermore, datagrams can arrive out of sequence.**Q8: What data information does a Datagram carry?**A: Each datagram carries sufficient information like source address, destination address, and data to be routed and delivered properly, without relying on the earlier exchanges between the source and destination systems. **Q9: What role does Datagram play in Internet Protocol (IP)?**A: In IP, the term “datagram” is used to describe a packet of data that can be routed and delivered as a unit, often used in internet communication for speed and efficiency. **Q10: How are Datagrams and Transmission Control Protocol (TCP) related?**A: TCP and Datagrams are both used in the transport layer of the Internet Protocol, but they are on opposing ends of the spectrum. TCP is a connection-oriented protocol that ensures data delivery, while Datagrams used in UDP are connectionless and don’t guarantee delivery or correct sequence.

Related Finance Terms

  • Packet
  • Internet Protocol (IP)
  • Transmission Control Protocol (TCP)
  • User Datagram Protocol (UDP)
  • Network Layer

Sources for More Information

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