TCP Vs UDP – Which packet transmission method is better?

TCP and UDP are two great packet transmission methods used to transmit data packets over the internet. Which one should you go for transmission of your user data to a given destination?

TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) are two of the most widely and commonly used data and information protocols in routers and software like VPNs. They are used to send data packets over the internet, both making use of the transport layer that the IP protocol provides to determine the address of the data’s destination. They have similar objectives, but achiever them using differing protocols, which makes them appeal to users with different objectives. This comparative review should help a potential user identify the one of the two, which would best suit their needs.

What are the differences between TCP and UDP?

Feature	TCP	UDP
Block boundaries	No	Yes
Header size	20 bytes	8 bytes
Sequencing of data	Yes	No
Speed	Slower	Faster
Acknowledgement segments	Yes	No
Requires established connection	Yes	No
Supports broadcasting	No	Yes
Protocol used	Handshake	Connectionless

TCP Vs UDP- How do they compare?

Error checking

TCP and UDP both have certain error checking mechanisms that are employed to the data that they transmit. TCP is designed to provide acknowledgement and flow control of data and is therefore equipped with extensive and detail oriented error checking protocols and mechanisms. On the other hand, UDP has basic error checking protocols through checksums after which it discards any packets that have been found to be erroneous. Therefore, TCP has a more extensive capacity to detect error, and is better because it facilitates error recovery.

Flow control

TCP uses a meticulous flow control mechanism that makes use of a send buffer and a receive buffer, It stores data in the send buffer before it is received in the destination’s receive buffer. The receive buffer has a packet limit and communicate this to their users therefore, if the receive buffer is full, then the user cannot send any more data and when a packet is received, the sender is informed of the amount of space that is available. UDP on the other hand has no flow control resulting in packets either arriving in a continuous stream, in no particular order, or being dropped. TCP is better because its flow control ensures that no data is lost in transit.

Speed

The speed of a TCP or UDP connection can only be conclusively measured in regard to a particular device, and with a particular set of circumstances. However, such tests should show a clear pattern indicating that TCP is slower than UDP, because it has a lot of functions to complete including setting up the connection, flow control and error checking.

TCP Vs UDP- A comparison review

TCP

Transmission Control Protocol, abbreviated TCP, is a connection oriented data packet transmission protocol that uses the IP protocol to allow computers to communicate. One of its most impressive features is its error checking. It not only provides extensive error checking, but also allows and facilitates error recovery. It establishes its connection with the aid of a handshake process that works in a three-way format that involves first acknowledging and initiating a connection, followed by the data transmission process and the process concludes when the connection is closed by terminating a virtual circuit. TCP guarantees that not only will the data be delivered to the intended user, but also that the packets will arrive at the end destination in the exact order that they were sent. It is therefore the go to option for application processes that prioritize reliability over timing like email, file transfer protocol and World Wide Web applications like HTTPS and HTTP.

Pros

• It works independently of the user’s operating system
• It supports a wide range and number of routing protocols
• It can be used to enable inter-networking between organizations
• It allows the user to set up and establish a connection between computers
• It can work between computers of different types
• It allows for independent operation
• Its model has a client server infrastructure that is highly scalable

Cons

• It requires all the data to be explicitly asked before concluding a transmission
• It is not suitable for multicast or broadcast transmissions
• It has no block boundaries (The user has to create their own)
• Replacing of protocol is difficult

UDP

User data protocol, abbreviated to UDP, is a data transmission protocol that uses IP address protocols to continuously send datagrams to an intended recipient. Its most impressive feature is that it is connectionless, which ensures a high packet transmission speed and allows for multicast as well as broadcast transmission. It has basic error checking protocols, the most common of which is checksums, which assumes that error correction is not the role of the application. This results in the discarding of erroneous packets and transmission of the remaining ones, without a window for error recovery. It is also unconcerned with the recipient status and will continue to send data packets regardless of whether the recipient receives them or not. It has no flow or congestion control which results in data arriving at the recipient in an arrangement and order that may be different from the one it was outputted in. UDP is widely used in time sensitive applications and by servers that serve a large client base as well as online games and Domain Name Systems.

Pros

• It is not restricted to a connection based model of communication
• Its application is bandwidth sensitive and endures packet loss
• It has a low start up latency
• It allows for multicast and broadcast transmission
• It includes block boundaries
• The end user receives the packets unmanaged

Cons

• It may deliver data that is out of order
• Data may be delivered twice or not at all
• There is packet loss with no option of retransmission
• It has no flow control and congestion control

Conclusion

TCP and UDP are both impressive data transmission avenues. TCP is best suited for situations where the both the server and the client send packets independently at a given time and it is acceptable to have an occasional delay, like emails. UDP, on the other hand, is best suited for use with multimedia broadcasting like VoIP and would be perfect in the situation that an occasional delay is unacceptable and the server and client send packets separately, like multiplayer games.

Verdict- So which is better, TCP or UDP?

TCP is the ideal choice between the two because despite its associated overhead, it secures a longer connection time and is more reliable, with a lower chance of packet loss.

FAQs

Does HTTP use TCP or UDP?

HTTP makes use of TCP. This is because it is designed to guarantee delivery of information packets via the three-way handshake structure that is used in TCP. It is also required to allow for re-transmission of packets that may be lost, which UDP cannot do.

What is the difference between TCP and IP?

TCP and IP need to work together to ensure that data is transmitted from one user to another, as required, hence they have different roles in the process. TCP is responsible for the delivery of the data packet and IP is responsible for the addressing that is required for the packet to reach its destination. Take the data packet as a letter that requires delivery, IP obtains the required address and gives it to TCP that guarantees the delivery of the letter to that address.