Capturing a TCP handshake with Wireshark

Simplified routing and routing tables

Routing is one of the most fundamental mechanisms in computer networking. It is the process by which data packets travel from one network to another until they reach their destination. Understanding how routing works is essential for anyone entering ...

Adjust the subnetwork for a need

**Theoretical Recap** A subnet (subnetwork) is a logical subdivision of an IP network. The core tool for defining subnets is CIDR (Classless Inter-Domain Routing) notation, written as an IP address followed by a prefix length (e.g., 192.168.1.0/24). ...

Calculate the /24 and /26 address range

**Theoretical Recap** An IP address in IPv4 is a 32-bit number divided into two parts: the network portion and the host portion. CIDR notation (Classless Inter-Domain Routing) expresses this split using a suffix like /24 or /26, which indicates how m...

CIDR subnets and notation

Understanding how IP addresses are organized and divided is a fundamental skill for anyone working in cybersecurity or network administration. You have already explored ports, transport protocols, and packet capture with tools like Wireshark and Nmap...

Filter UDP DNS traffic

**Theoretical Recap** DNS (Domain Name System) is the protocol responsible for translating human-readable domain names (e.g., google.com) into IP addresses that machines can route. By default, DNS operates over UDP on port 53 — a deliberate design ch...