Network Media, Devices, and Standards

• Hub


  A device with multiple RJ 45 connectors, acts as a connection point for a wired network
• Hub


  • Considered a dumb device, does not learn any addressing and does not use any addressing to make forwarding decisions
  • An OSI layer one device
  • A multiport repeater, whatever signal is received on one port, it is repeated out of all other ports
• Switch


  The primary device for interconnecting wired components in a modern IT network
• Switch


  • Looks like a hub, but is a smarter version of a hub
  • An OSI layer 2 device, learns which MAC address lives on each of the ports and keeps a table of a MAC address to port assignment that it uses for making forwarding decisions so that data is sent only to the correct recipient
• Wireless Access Point


  Acts as a bridge and takes all of the wireless clients and bridges it onto the wired network
• Wireless Access Point


  • An OSI layer 2 device, uses MAC Addresses to make forwarding decisions
• Router


  An OSI layer 3 device, moves data between one IP network and another, like between your private network at home and the public network that is the Internet or between two internal IP subnets within a larger organization
• Router


  • Uses IP addressing to make forwarding decisions to ensure that the data is being sent not only to the right network, but to the right host
• Firewall


  Filters traffic based on set of rules and determines if the traffic should be allowed to pass or whether it should be dropped
• All-in-one device


  A SOHO (Small Office/Home Office) device where one physical device does the functionality of multiple devices
• Modem


  Allows your ISP to give service to your house or your business
• Twisted Pair


  The most common type of network cable, also known as Ethernet cables
• Twisted Pair


  • UTP Cable vs. STP cable, STP cable is more resistant to EMI
  • Different categories of twisted pair cable, Cat3/4/5 are outdated, Cat5e/6/6a are the current standards
• RJ45


  Used for Networking Devices
• RJ11


  Used for telephones
• Coaxial


  Primarily used to go from a cable jack on the wall to a cable modem in order to have cable based Internet
• Fiber optic cabling


  Very different from coaxial and/or twisted pair, does not use copper cabling or electricity to transmit data, uses a light source and light pulses
• Fiber optic cabling


  • Faster, can go for very long distances, completely immune to any EMI or electromagnetic interference
• Single mode fiber signal (SMF)


  Uses a high quality light source (usually a laser) to send a stream of light through the center of the core, can go for very long distances
• Multimode fiber signal (MMF)


  Uses a weaker light source (generally an LED), sends multiple wavelengths of light at different bounce angles, multiple transmissions can go through at once
• Single mode fiber


  Faster and can go for longer distances, but more expensive
• Multimode fiber


  Less expensive, but ideal for shorter cable runs
• Patch Cable


  A short version of a standard Ethernet cable with RJ45 connectors, used to connect end devices to wall jacks
• Crossover Cable


  Used to connect like devices (PC to PC, router to router) with no switch or hub in between
• Networking Standards

  • 802.11a is 54 mbps and 5 GHz
  • 802.11b is 11 mbps and 2.4 GHz
  • 802.11g is 54 mbps and 2.4 GHz
  • 802.11n is 600 mbps and 2.4 GHz & 5 GHz
  • 802.11ac is 1300 mbps (1.3 gbps) and 5 GHz
  • 802.11ax(Wi-Fi 6) is 9600 mbps (9.6gbps) and 2.4 GHz & 5 GHz (1 GH & 6 GHz)
• The cat3 cable does not support data transmission speeds of 1000 Mbps (1 Gbps). Cat3 cable is an older type of twisted pair cabling that was primarily used for telephone wiring and the early Ethernet networks. It typically supports maximum data transmission speeds of up to 10 Mbps and is suitable for applications using 10Base-T Ethernet.
• cat4 cable is considered rare and is not commonly mentioned or used in contemporary network installations. Cat4 was designed to support frequencies up to 20 MHz and data rates up to 16 Mbps. It was primarily used in Token Ring networks, rather than Ethernet systems.

  With the rapid advancement in network technology, Cat4 was quickly superseded by higher categories of cable that offer significantly greater bandwidth and data rate capabilities.
• cat5 cable, also known as Category 5 cable, is a type of twisted pair cable that is commonly used in networking environments. When it was widely used, CAT5 typically supported Ethernet networks running at 10 or 100 Mbps (megabits per second). However, it's important to note that while CAT5 cable is rated officially for up to 100 Mbps, it can sometimes handle speeds up to 1 Gbps (Gigabit Ethernet) over short distances with a good quality cable and network. Most modern networks have moved beyond CAT5 cable to CAT5e (enhanced CAT5) or higher categories like CAT6, CAT6A, and CAT7.
• CAT5e (Category 5 enhanced) cable supports network speeds of up to 1 Gbps (1000 Mbps) at 100 MHz. It is an improved version of the original CAT5 cable, designed to reduce crosstalk more effectively. This makes CAT5e a common choice for home and business networks, providing sufficient bandwidth for a variety of applications including internet access, file sharing, and media streaming, all under the conditions of appropriate distance and network setup. It can support Gigabit Ethernet connections over distances up to 100 meters.
• CAT6 cable can support up to 10 Gbps, but with some specific conditions. CAT6 cable is an advancement over previous versions like CAT5e, and it offers higher performance levels.
• cat6a is an enhanced version of the cat6 and is designed to support 10 gigabit ethernet (10GBASE-T) over longer distance with better performance. Can support 10GBASE-T transmission distances up to 100 meters suitable for high-speed.
• Coaxial cables transmits electricity down a single copper wire. The wire thickness determines transmission distance. Coaxials are rarely used for enterprise networks. Coaxials are primarily used for residential internet service cable modems.
• Fiber cables contains tiny plastic fibers and transmits light pulses instead of copper.
• Single Mode Fiber (SMF): transmits data over long distances with high bandwidth and low signal loss. SMF offers high performance and is the preferred choice for high-speed.
• Multimode Fiber (MMF): offers cost effective solutions for short distance needs, provides flexibility, ease of installation, shorter transmission distances and lower bandwidth compared to single mode fiber. MMF is less suitable for high-speed connections.
• A crossover cable is a type of Ethernet that connects similar devices directly together.
• A patch cable is used to connect an end unit to a power source.
• A patch panel is designed to organize cables within a network or telecommunications system.
• A twisted pair copper cable transmits electrical signals over copper wires. Twisted pair copper cables consists of four pairs of twisted copper wires (eight wires in total). The twists reduce crosswalk interference.
• Shielded Twisted Pair: provides extra protection against electro-magnetic interference (EMI).