Security practitioners for decades have advised people to limit DNS queries against their DNS servers to only use UDP port 53. The reality is that DNS queries can also use TCP port 53 if UDP port 53 ...

IP tools, when used properly, can help system builders tackle set-up and configuration chores, speed troubleshooting and problems resolution, and address all kinds of security issues and concerns. A ...

Data packets travel to and from numbered network ports associated with particular IP addresses and endpoints, using the TCP or UDP transport layer protocols. All ports are potentially at risk of ...

With UDP, I don't have connections, but the principle is the same. When I get a UDP packet, I get the ephemeral source port as part of the source socket address, and when I need to send something back ...

What is TCP/UDP port 27? I've looked it up in IANA's list of well-known ports and it came up as nsw-fe, or more appropriately, "NSW User System FE", but just what the hell is it? I've been told it was ...

Security continues to be the biggest concern for IT managers and, in turn, design engineers developing firewall systems. With more viruses popping up and hackers attacking more often, corporations are ...

Port Query (PortQry.exe) is a command-line utility in the Windows operating system that you can use to help troubleshoot TCP/IP connectivity issues. The tool reports the port status of TCP and UDP ...

A Port basically serves as an interface between your computer and the internet or other computers in the network. Every communication over the web is exchanged using these ports, so they are an ...

Network address translation and port address translation (NAT/PAT) originally were solutions for the depletion of the IPv4 addresses, and now are used by growing corporations to securely expand their ...