Local Area Network Basics: Understanding Modern LANs
Modern LANs run on high-speed switches, PoE, structured cabling, and Wi-Fi 6/7 APs. Here is a clean walkthrough of the components and how they fit together.
Jaime
Latest posts — page 61
Understanding IPv4: The Internet’s Original Addressing System
IPv4 gives every networked device a 32-bit address split across classes and subnets. Here is how IPv4 addressing works, why it still runs the internet, and its limits.
Straight-Through vs Crossover Ethernet Cables: A Clear Guide
Straight-through cables connect PC to switch or router; crossover cables connect like to like. Here is the pinout, color code, and when Auto-MDIX makes it moot.
Understanding IP Routing: A Beginner’s Guide
IP routing is how routers pick a path and forward packets between networks. Here is the routing table, next hop, and longest-prefix match in simple terms.
How to Enable SSH on Cisco Routers and Switches
Enabling SSH on a Cisco router or switch takes a hostname, domain name, RSA keys (3072-bit minimum on current IOS XE), a local user, and vty line login. Full config plus real verification output.
Essential Cisco Commands: 50 Proven Commands
The Cisco IOS commands you actually run every day, grouped by job, with real output captured on IOS XE 17.18: status checks, interfaces, routing, switching, debugging, and filters.
Configuring SVIs (Switch Virtual Interfaces) for Inter-VLAN Routing
SVIs (Switch Virtual Interfaces) are logical VLAN interfaces that enable a Layer 3 switch to route between VLANs and provide management access. Master SVI creation, IP routing enablement, and troubleshooting SVI states.
Show Interfaces Status on Cisco Switches: Reading Every Column
One line per port: state, VLAN, duplex, speed. How to read every column of show interfaces status, decode all four status values, and recover an err-disabled port - with real Catalyst output.
How to Factory Reset a Cisco Switch
Three reset methods that actually apply to Catalyst switches - write erase, factory-reset all, and Mode-button recovery - with real Catalyst 9000 output, and the config-register myth retired.
How to Check CDP Neighbors on Cisco ASA
The Cisco ASA does not run CDP. Here is why, how to find the ASA from the connected switch with CDP, LLDP and the MAC table, and what to run on the ASA itself.
How to Set IP Address on Cisco Switches
A Cisco switch gets its management IP on an SVI (usually VLAN 1 or a dedicated mgmt VLAN). Here is the config, the default gateway step, and SSH-readiness.
How to Import Files to Cisco Router
Get files onto a Cisco router with TFTP, SCP, or USB. Here is how to set up a TFTP server, use copy tftp: flash:, and avoid the common transfer gotchas.