Transmission Control Protocol, or TCP, is one of the core protocols of the Internet Protocol Suite; a vast number of protocols are based upon TCP, such as SMTP, DNS, HTTP and so on. The protocol provides means to perform reliably an ordered sequence of binary data. In case reliability is not a concern and the data order isn’t important, a lighter protocol sich as UDP may be used.
TCP can be used to test the very possibility of establishing connection and sending/receiving data, just by opening a port and trying to send data/receiving data. This means of network monitoring goes well with majority of commonly used protocols, such as SMTP, IMAP, HTTP and so on.
SMTP – host monitoring
SMTP monitoring, as part of more general mail services monitoring may be used in conjunction with POP3 and IMAP monitors, as well as with monitors designed to watch authentication and general connectivity. Note that if test messages are used, the absence of such message should be treated as an alert as well.
DNS Monitor is a simple type of IPHost Monitor. DNS, or Domain Name Service is the heart of Internet, since this protocol allows to translate human-readable …
HTTP/HTTPS Monitor is used to check the Web site presence and test whether the contents of the address match certain criteria. HTTP, or Hypertext Transfer …