IntroductionDuring a security investigation, I needed to verify whether SMB (TCP/445) was being used on a Windows Server, so I am documenting the investigation method as a memo.The key point this time ...

When I use the netstat command to look at the open TCP/IP connections on my PC, there are connections that should be closed that are in the TIME_WAIT state. What is this, and why do connections stay ...

I have a VM in EC2 that has been running dual stack IPv4 and IPv6 successfully for over a year now, but things have recently broken on the IPv6 side. My VPC has a /20 block in RFC1918 space, and a /64 ...

It’s hard to imagine now, but in the mid-1980s, the Internet came close to collapsing due to the number of users congesting its networks. Computers would request packets as quickly as they could, and ...

IntroductionOn September 28, 2026, a small VPS running WordPress received an HTTPS socket timeout notification from an ...

Transmission Control Protocol (TCP) is a standard protocol on the internet that ensures the reliable transmission of data between devices on a network. It defines how to establish and maintain a ...

Your handler finishes the in-flight work and exits. It is a reasonable story. I wanted to know if it is true. Not plausible.

I've read that there is an "application" that allows computers to communicate without exposing or opening ports to the Internet. Is this possible, and if so, will it create a safer Internet ...

To: Donald Hunter <donald.hunter-AT-gmail.com>, Jakub Kicinski <kuba-AT-kernel.org>, "David S. Miller" <davem-AT-davemloft.net>, Eric Dumazet <edumazet-AT-google.com ...