| TCP is a connection-oriented protocol. Connection-orientation means that the communicating devices should establish a connection before transmitting data and should close the connection after transmitting the data. | UDP is the datagram oriented protocol. This is because there is no overhead for opening a connection, maintaining a connection, and terminating a connection. UDP is efficient for broadcast and multicast types in order of network transmission. |
| TCP is reliable as it guarantees the delivery of data to the destination router. | The delivery of data to the destination cannot be guaranteed in UDP. |
| TCP provides extensive error checking mechanisms. It is because it provides flow control and acknowledgement of data. | UDP has only the basic error checking mechanism using checksums. |
| Sequencing of data is a feature of Transmission Control Protocol (TCP). This means that packets arrive in-order at the receiver. | There is no sequencing of data in UDP. If the order is required, it has to be managed by the application layer. |
| TCP is comparatively slower than UDP. | UDP is faster, simpler, and more efficient than TCP. |
| Retransmission of lost packets is possible in TCP, but not in UDP. | There is no retransmission of lost packets in the User Datagram Protocol (UDP). |
| TCP has a (20-60) bytes variable length header. | UDP has an 8 bytes fixed-length header. |
| TCP is heavy-weight. | UDP is lightweight. |
| TCP doesn’t support Broadcasting. | UDP supports Broadcasting. |
| TCP is used by HTTP, HTTPs, FTP, SMTP and Telnet. | UDP is used by DNS, DHCP, TFTP, SNMP, RIP, and VoIP. |
