CCNA WK 2 Summary PDF

1. What Do These Terms Mean? ​ Network: A collection of interconnected devices. ​ Wi-Fi: Stands for Wireless Fidelity, a technology for wireless networking. ​ Bandwidth: The amount of data (bits) that can be transmitted in 1 second. ​ Binary: A system of numbers consisting of only 0s and 1s...

1. What Do These Terms Mean? ​ Network: A collection of interconnected devices. ​ Wi-Fi: Stands for Wireless Fidelity, a technology for wireless networking. ​ Bandwidth: The amount of data (bits) that can be transmitted in 1 second. ​ Binary: A system of numbers consisting of only 0s and 1s, also referred to as bits. ​ Triple Play Services: The ability to send three types of traffic (e.g., Voice, Video, Data) over a single medium. ​ QoS (Quality of Service): A mechanism to prioritize specific types of traffic (e.g., Voice, Video, Data) based on their sensitivity. 2. Networking Components and Concepts ​ Networks are compared to transport systems, with various types of devices and configurations based on use cases. ​ Types of Networks: ○​ LAN (Local Area Network): Covers a room, floor, building, or campus. Owned by the premises' owner. ○​ MAN (Metropolitan Area Network): Spans a city and typically relies on an ISP. ○​ WAN (Wide Area Network): Covers large distances, beyond city limits, using multiple service providers. 3. Traditional vs. Converged Networks ​ Traditional Networks: ○​ Separate mediums for each type of traffic (e.g., Voice, Video, Data). ○​ Examples: PSTN for voice, dial-up for internet, circuit-switched networks. ​ Converged Networks: ○​ A single medium handles all types of traffic (Voice, Video, Data). ○​ Utilizes IP networks and technologies like Fiber to the Home (FTTH). ○​ Challenges: Delay, jitter, and data loss. QoS ensures better performance. 4. OSI and TCP/IP Models ​ OSI Model: ○​ Layer 7: Application (Interface for applications). ○​ Layer 6: Presentation (Data formatting, encryption, compression). ○​ Layer 5: Session (Authentication, session management).  ○​ Layer 4: Transport (Reliable transmission using TCP or faster communication using UDP). ○​ Layer 3: Network (Logical addressing, routing). ○​ Layer 2: Data Link (Switching, VLANs). ○​ Layer 1: Physical (Hardware, cables, connectors). ​ TCP/IP Model: ○​ Application, Transport, Internet, Network Access layers. 5. Important Networking Concepts ​ Packet Switching vs. Circuit Switching: ○​ Circuit Switching: Dedicated paths, mainly for voice. ○​ Packet Switching: No dedicated paths, mainly for data, efficient bandwidth usage. ​ Frames and Packets: ○​ Data is divided into packets (e.g., Maximum Transmission Unit - MTU). ○​ Standard MTU = 1500 bytes. ○​ Larger MTUs (e.g., Jumbo Frames) improve efficiency. 6. TCP vs. UDP ​ TCP (Transmission Control Protocol): ○​ Reliable, connection-oriented, ensures data integrity. ○​ Slower, with a 20-byte header. Used for applications needing high reliability (e.g., file transfers). ​ UDP (User Datagram Protocol): ○​ Fast, connectionless, less reliable. ○​ 8-byte header. Used for time-sensitive applications (e.g., video streaming). Transport Medium Not to be confused with the transport layer (Layer 4).​ Just like vehicles require roads to commute, networks require a medium for data transport. The transport medium consists of specific cabling types that carry signals from one device to another. Important Cabling Types Physical Medium The physical medium allows data to flow between network nodes. Various media types are used in networking, including: 1.​ Copper Cabling ○​ Carries information using electrical pulses. 2.​ Fiber Cabling ○​ Transmits information using light pulses. The World of Copper Cabling Twisted Pair Cabling Commonly referred to as "Twisted Pair," this type includes two insulated copper wires twisted together to minimize interference and noise. ​ Shielded Twisted Pair (STP) or Foiled Twisted Pair (FTP) ​ Unshielded Twisted Pair (UTP) Connectors for Copper Media 1.​ 8P8C Standard (commonly called RJ45) ○​ "RJ" stands for "Registered Jack." 2.​ Examples of Connectors: ○​ Nexans GG45 (for CAT-6a) ○​ Zmax Plug with PCB ○​ Siemon TERA (for CAT-7a and CAT-8) ○​ ARJ45 Data Rates on Copper The table below outlines the different categories of copper cables, their capabilities, and applications: Categor Max Data Frequency/Bandwidt Connector Application y Rate h CAT1 Up to 1 1 MHz 6P2C/RJ11 Voice (Old Telephone Cable) Mbps CAT2 Up to 4 4 MHz 6P2C/RJ11 Token Ring Networks Mbps CAT3 Up to 10 16 MHz RJ11/RJ45 10BASE-T Ethernet Mbps CAT4 Up to 16 20 MHz DB9/RJ45 Token Ring Networks Mbps CAT5 Up to 100 100 MHz 8P8C/RJ45 Fast Ethernet Mbps CAT5e Up to 1 100–350 MHz 8P8C/RJ45 Gigabit Ethernet Gbps CAT6 Up to 10 250–550 MHz 8P8C/RJ45 10G Ethernet (up to 55m) Gbps CAT6A Up to 10 500–550 MHz 8P8C/RJ45 10G Ethernet (up to 55m) Gbps CAT7/7A Up to 100 600 MHz Non-RJ45 40GBASE-T (up to 55m), Gbps 100GBASE-T (15m) CAT8 Up to 100 2000 MHz RJ45/Non-R 100G Ethernet (up to 15m) Gbps J45 Note: The maximum length for twisted-pair cables is typically 100 meters. Types of Copper Cabling 1.​ Straight Cable ○​ Connects different devices (e.g., switch to router, PC to switch). 2.​ Cross Cable ○​ Connects similar devices (e.g., switch to switch, PC to PC). 3.​ Rollover Cable  ○​ Used to configure networking equipment. Copper Wiring in Enterprises Enterprise networks require proper cabling, which includes: 1.​ Patch Panels ○​ Copper cables are terminated at patch panels in network racks. 2.​ Punch Tool ○​ Used for terminating cables on the back of patch panels. 3.​ Patch Cords ○​ Connect devices to patch panels and switches. Example Setup: ​ Patch Panel → Patch Cord → Switch