by Kristof Vandenborn | Jun 19, 2023 | Firewall, Networking, Security
What are port numbers? As we were discussing the OSI model and the difference between TCP and UDP we already learned some of the bits how protocols work on the transport layer. Together with the transport protocol used (these are not limited to TCP and UDP only but...
by Kristof Vandenborn | Jun 15, 2023 | Firewall, Networking
Let’s spell out the acronyms first. TCP stands for Transmission Control Protocol and UDP stands for User Datagram Protocol. In networking we often use the OSI model as a reference to clarify on which layer of the OSI model a protocol is used. We did an article...
by Kristof Vandenborn | Jun 14, 2023 | Networking, Security
OSI stands for Open System Interconnection and Its model describes via which steps (called layers) computers take to communicate over a network. The seven layers are from top to bottom: Layer nameFunctionApplication layerHuman interaction with the application and the...
by Kristof Vandenborn | Jun 12, 2023 | Firewall, Networking
FTP stands for File Transfer Protocol. As the name implies it’s protocol that facilitates the transfer of a file from one client over the network to another client. FTP modes: active versus passive FTP connections can be made using one of these two modes. In...
by Kristof Vandenborn | Jun 7, 2023 | Networking, Security
SSH or Secure SHELL is an authentication protocol that support several authentication methods. (Certificate based, username/password) But we have telnet? Remember what I told you about Telnet in this article? Yes indeed, it sends all packets in clear-text over the...
by Kristof Vandenborn | Jun 5, 2023 | Networking
Telnet is an application (protocol) that can be used to manage devices remotely. So if you want to log in to a router, switches or any other device that has a telnet client installed, you can use telnet. telnet 10.0.0.1 <any specific port/when not specified 23 is...
