CCNA Training

  IPv4 Address Class Ranges Class First Octet Range Full IP Range Purpose Class A 1 – 126 1.0.0.0 – 126.255.255.255     Large networks Class B 128 – 191 128.0.0.0 – 191.255.255.255     Medium networks Class C 192 – 223 192.0.0.0 – 223.255.255.255     Small networks Class D 224 – 239 224.0.0.0 – 239.255.255.255     Multicast Class E 240 – 255 240.0.0.0 – 255.255.255.255     Experimental/Reserved Private IP :  Class A - 10.0.0.0 - 10.255.255.255 Class B - 172.16.0.0 - 172.31.255.255 Class C - 192.168.0.0 - 192.168.255.255 🖥️ Private IP vs Public IP Address 🧠 Definition: Private IP Address: Used inside a private network (LAN) — identifies devices like PCs, printers, and routers within a local area. Example: 192.168.1.10 Public IP Address: Used on the Internet — identifies your network or device globally so it can communicate with other networks. Example: 8.8.8.8 🔹 Key Differences F...

  🌍 What is the Internet? 🧠 Definition: The Internet is a global network of interconnected computers that communicate with each other using standard protocols (like TCP/IP) to share information, resources, and services. 🔹 5 Simple Key Points Global Connection of Networks: The Internet links millions of private, public, academic, business, and government networks worldwide. Uses TCP/IP Protocols: Communication across the Internet is based on the Transmission Control Protocol/Internet Protocol (TCP/IP) suite. Provides Services: The Internet enables services like the World Wide Web (WWW) , email , file transfer (FTP) , video streaming , and cloud computing . Decentralized System: No single organization owns the Internet — it is a distributed network maintained by multiple ISPs and organizations globally. Accessed via ISPs: Users connect to the Internet through an Internet Service Provider (ISP) using devices like modems, routers, and computers. ...

  💻 NIC (Network Interface Card) 🧠 Definition: A Network Interface Card (NIC) is a hardware component that allows a computer or device to connect to a network (wired or wireless) and communicate with other devices. 🔹 Key Points (5 Simple Points) Network Connection Device: NIC acts as the interface between a computer and a network , enabling data transmission and reception. Unique MAC Address: Every NIC has a unique MAC address burned into it — used for device identification at the Data Link Layer (Layer 2) of the OSI model. Types of NICs: Wired NICs → use Ethernet cables (RJ-45 port). Wireless NICs → use Wi-Fi (radio signals). Functions: Converts parallel data (inside PC) into serial data (on the network) and handles framing, addressing, and error detection . Placement: Can be built into the motherboard or installed as an expansion card (PCI/USB). Test if NIC is working ping 127.0.0.1 loopback IP of the NIC  ⚙️ Technical Summ...

  Crimping Straight-Through Cable vs Cross-Over Cable A crimping tool is used to attach RJ-45 connectors to Ethernet cables. The difference between Straight-Through and Cross-Over cables is the wiring order of the colored wires. ----------------------------------------------------------------------------------------------------------------------- Group 1 Devices Examples: Computers (PCs), Servers, Routers Group 2 Devices Examples: Switches, Layer3 Switches..  Straight through - Different group devices  Cross over - Same group devices..  ---------------------------------------------------------------------------------------------------------------------- Straight-Through Cable Used to connect different devices , such as: PC ↔ Switch PC ↔ Router Switch ↔ Router Both ends use the same standard (usually T568B). T568B Wiring Order (Pin 1 to Pin 8) Pin Color 1 White/Orange 2 Orange 3 White/Green 4 Blue 5 White/Blue 6 Green 7 White/Brown 8 Brown End A (T568B) ...