Muhammad Khattak
Routing and switching specialist, CCNA certified, with extensive experience in network configuration and troubleshooting. Covers OSPF, EIGRP, VLAN management, and advanced routing concepts.
Understanding Ping Indicators and Ping Results in Cisco IOS
The ping command is a fundamental network troubleshooting tool that uses the Internet Control Message Protocol (ICMP), as defined in RFC 792, to test connectivity between devices. It is essential for CCNA (ICND1, ICND2) and CCNP (ROUTE, SWITCH, TSHOOT) exam preparation, helping students verify Layer 3 connectivity by interpreting ping results correctly. This guide covers...
Cisco Router File System – Exclusive Details (Updated 2025)
The Cisco IOS File System (IFS) has different directories, depending on the device. The IFS also allows the creation of subdirectories in flash memory or on a disk. The figure below displays the output of the show file system command, which lists all of the available file systems on the router. 📂 File System Entries...
Master IP Address Planning for Unbeatable Small Network Success (Updated 2025)
IP address planning is crucial for implementing a small network, ensuring all hosts have unique addresses. The network administrator must document the IP addressing scheme. The administrator should also maintain IP addresses based on the type of device to configure the addresses. The different types of devices that require IP addresses are:- Servers: Host critical...
Small Network Topologies – Exclusive Details (Updated 2025)
This guide is designed for network professionals using Windows (e.g., 10/11) or Linux (e.g., Ubuntu 22.04) systems. Network configuration can be managed via Command Prompt (cmd) on Windows or terminal (Ctrl + Alt + T) on Linux, with tools like ipconfig (Windows) or ifconfig (Linux) for IP management. These OS platforms are essential for implementing...
Domain Name System (DNS): Message Format, Hierarchy, and Cisco Configuration
DNS translates human-readable domain names, like networkustad.com, into machine-readable IP addresses, like 64.91.237.241. It’s the backbone of modern networking. Without it, you’d need to memorize an IP address for every site you visit. For CCNA and CCNP students, DNS matters beyond just browsing the web. It underpins how devices find each other across IP networks,...
Dynamic Host Configuration Protocol(DHCP) Updated 2025
The Dynamic Host Configuration Protocol (DHCP) is a cornerstone of modern networking, automating IP address allocation to streamline network management. For CCNA and CCNP students, understanding DHCP is critical, as it simplifies the configuration of IP addresses, subnet masks, default gateways, and DNS servers in both small and large networks. Unlike static IP addressing, which...
TCP Connection Establishment and Termination
All application processes on a server use unique port numbers. A network administrator can use default ports (e.g., 80 for HTTP, 21 for FTP) or configure custom ports manually, ensuring no conflicts. An active server application listening on an open port means the transport layer accepts and processes segments addressed to that port number. Every...
Netstat Command, Troubleshoot Connections in Seconds Exclusive 2025 Guide
Knowing which active TCP connections are open on a networked host is crucial, especially with the 2025 IoT growth. The netstat command is a vital tool for verifying these connections on Windows (e.g., 10/11) or Linux, addressing security risks from unexplained connections, a key concern as of 2025 This netstat command shows detailed information about...
VLSM Insights: Avoid IP Waste with Precision Subnetting 2025 Guide
VLSM (Variable Length Subnet Masking) helps improve the use of IP address space, with applications in IPv6 internal segmentation as of June 2025. Using a variable-length subnet mask, we can assign LAN and WAN segments without wasting IP addresses. As shown in the scenario in the Figure below, the hosts in each subnetwork will be...
Master Subnetting Based on Network Requirement – Exclusive Guide 2025
Sometimes, the number of sub-networks is more critical than the number of host addresses per sub-network. For example, an organization wants to separate network traffic based on internal structure or department setup. In this case, subnetting based on network requirements is most important in determining how many bits to borrow. The addressing scheme must allow...