With TCP connections, on the other hand, lost packets are automatically re-requested, causing the entire transmission process to come to a standstill. This also results from the fact that the loss of individual packets only affects the quality of the transmission.
The ports are defined by numbers according to the proven pattern, with numbers between assigned to fixed services. UDP uses ports: Like TCP, UDP uses ports so that the packets are transferred to the correct subsequent protocols or the desired applications on the target system.However, if packets are also to be returned to the recipient, the UDP header can optionally also contain the source port. The respective packets are then sent to the preferred IP address, specifying the target port, without the computer behind them having to respond. UDP is connectionless: Data transport via UDP is characterized by the fact that it takes place without an existing connection between addressee and recipient.To understand how packet transmission works with the protocol in detail, it is useful to take a closer look at the properties of the User Datagram Protocol.
