The UDP and ICMP protocols are datagram oriented — communication is based on the exchange of individual messages (so called datagrams) among that exists (at the level of the network communication) no connection. The typical communication consists of one or several sequences request — response. Therefore we can suppose there is regular exchange of datagrams in small intervals, in fact it makes one relation (so called pseudorelation). If the interval is noticeably higher, we suppose new relation was started. This principle can be used for showing the UDP and the ICMP pseudorelations in the Current connections window (see chapter 7.3).

The ICMP protocol and UDP protocol options are used for setting the above described intervals .

The TCP protocol is relation based (first the relation, which the data is transferred in, is created). In this case we know exactly the time of creating and dropping the connection. If a small amount of data is transferred using a fast line the connection can last only a small time (often less than 1 second). In order to enable the user to watch the connection in the window Current connections (see chapter 7.3), it is left displayed for some time after the end of the connection. This time is set by the Closed TCP connections are kept displayed for option.