5: Comparing Local Networking Hardware: Big chunk of the exam!

Network Types

LANs

• Local Area Network(LAN): A group of computers connected by cabling and one or more network switches at one geographic location

  • May span a single floor in one building or multiple nearby buildings

  • LAN cabling and network devices are typically owned and managed by the organization that uses the network

• Most cable LANs are based on the Ethernet standards maintained by the IEEE 802.3

• The majority of LANs will use copper cabling, which uses electrical signaling to communicate data.

• The backbone or special Eth networks may use fiber optic cabling, which use pulses of light to communicate data.

WANs

• Wide Area Network(WAN): Spans multiple geographic locations

  • Ex: The internet

• A company dedicated to facilitating access to the Internet from local networks is called an Internet service provider(ISP)

  • Most private or enterprise WANS use cabling and equipment leased by an ISP to interconnect two or more separate LAN sites.

WLANs

• Wireless Local Area Network: a network type that uses radios and antennas for data transmission and reception.

  • Most are based on the 802.11 IEEE standard or WiFi.

• Wifi and Eth tech complement one another and are often used together as segments of the same network

  • This allows computers with wired and wireless adapters on the same LAN to communicate with each other.

  • Easily extendable by adding addition access points

  • Preferred for hard to reach areas in buildings.

  • Flexible.

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MANs

• Metropolitan Area Network: A specific network type that covers the equivalent of a city or other municipality.

  • Could mean a company with multiple connected networks within the same metropolitan area.

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PANs

• Personal Area Network(PAN): Refers to using wireless connectivity to connect devices within a range of a few meters.

  • Most common examples of this are Bluetooth devices and smartwatches that connect to one’s phone.

  • One of the most common and smallest networks

  • Printers, speakers, and video displays also count.

SANs💀🩵

• Storage Area Network(SAN): A specialized network that’s dedicated to storage devices.

  • Servers can connect to storage devices as if they’re directly attached

• Key characteristics of a SAN must include

  • A dedicated network independent from the LAN. Ensures other network operations is not interfered with

Networking Hardware

Network Interface Cards(NIC)

• Desktops tend to come with one Eth NIC by default.

  • Allows a network cable(RJ-45, so on) to be plugged in to connect to the network

  • Wireless adaptability must be installed on a separate card

• Laptops normally come with both an Eth and wireless NIC

  • Both are two separate adapters/cards

Hubs

• Legacy/extinct basically

• Allows multiple devices, plugged in via a LAN cable to allows machines to communicate.

• Dumb device because it sends signals outside all it’s ports to all devices instead of a specific device

• Performance is reduced by contentions

• Contention is when multiple devices on the same network try to transmit data over the same shared communication channel t the same time.

  • Causes collisions, which corrupts data packets making them unreadable

  • Data being destroyed causes both devices to back off and wait a specified period of time before trying again.

  • This negatively impacts network performance, especially as more devices are added

• Runs at Hal-Duplex 10/100 Mbps on Eth only

Switches

• Mogs hubs

• Forwards traffic to a specific device by learning the devices MAC address

• Allows each port to operate at full-duplex and full speeds

  • Required for Gigabit speeds and modern Eth for optimal performance standards.

• Unmanaged Switch: Works without any configuration.

  • Usually cheaper

  • Usually very few ports

  • less sophisticated

• Managed Switch: Comes with config interfaces that allows one to log into them

  • 1. Connect to the switch, type in the IP address of the switch in a browser.

  • 2. A splash screen should appear allowing one to type in the switch’s username and password.

  • More expensive for more functionality

  • Can make VLANs on these and access controllers

  • How configuration works depends on the manufacturer the switch is bought from.

  • Comes with a web or cmd line interface.

Power over Ethernet(PoE)

• Sends power over an Ethernet Cable

• Commonly used in areas were power is not easily accessible

• Uses a standard twisted pair cable

• How it works?

  • Eth cables contain 4 pairs of twisted copper wires, for a total of eight wires

  • Data only uses some of these wires or frequencies to transmit

  • PoE injects a direct current into the unused wires or it overlays it onto the data wires without interfering with network traffic.

• Commonly used for Wireless Access Points, IP security cameras, or VoIP phones,

• How the power travels?

• PoE circuit capabilities are usually embedded into switches, so power flows out through it’s ports

• PoE injectors is an alternate method

  • Plus a switch without the capabilities into an injector, plug the injector into a wall and power is injected through the cables.

  • Typically used for one off devices that need to be powered on a switch

Network Cable Types:

UTP(Unshielded Twisted Pair)

• One of the most common kind of cables

• A cooper wire that carries electrical signals

• Four balanced wire pairs twisted together, eight wires total.

• Insulated Jacket.

• Four pairs of conductors, eight total.

• Wires are twisted to reduce interference.

• Cables can be a maximum of 328 ft(100m) before signal strength decreases

• In real life, the max length cable that’s possible to find is 90-95 meters(295 to 312) IF you are lucky.

• On average 70-80 m cables are the maximum found on the market(231-264ft)

Shielded Twisted pair

• Cables with foil shielding around the copper cabling

• UTP with a foil coat.

• Useful when a network cable being near another strong source of EMI is unavoidable

• More expensive than UTP

• Not completely immune, but resistant to EMI.

• A small piece of the foil must be sticking out, and the cable needs to be grounded

CAT standards.

• CAT6 isn’t important for the exam

• CAT5 is mostly extinct since it’s really old.

• Visually CAT5 is the same as 5e, but 5e is 10x faster

• CAT 6 feels and looks different from both CAT5 cables. It’s thicker and runs at a higher frequency

• CAT6A runs at the highest frequency, but still as the same speed as CAT 6.

Copper Cabling Installation/Testing Tools

• Cable crimper

• Punch down Tool: Used in patch panels and wall boxes

• Cable Tester: Checks connectivity and that all cables are placed in the correct order

• Toner Probe: Help someone locate a cable in the wall or something like that.

Optical Cabling/Fiber Optic

• Two types: Single-mode and multi-mode cabling

• Single-Multi Mode

  • goes outside most times

  • covers longer distances

• Multi-Mode

  • Used over shorter distances

  • Used indoors(Server rooms, etc)

• Connector Types:

  • ST: Straight Tip

  • Subscriber connector

  • LC: Lucent connector'

• Made of glass.

• Reflects laser or optical light

  • optical light doesn’t travel as far as laser light

• Don’t bend this

• Not susceptible to EMI

Coaxial Cabling

• Older, not quite legacy YET

• Frequently used in Analog TVs

• Type from country to country

• Solid core with copper or steel braiding

• Can be used as network cables, less frequent

• Has a Coaxial F-connector

Wireless Networking Types

Access Points

• An access point is a device that broadcasts a signal wirelessly within a home or office building.

• When plugged in, the access point with further broadcast a wireless network from a router

• More useful in bigger buildings.

• Follows the IEEE 802.11 wireless standard

• There are relevant 4 standards:

  • 802.11a

  • 802.11b

  • 802.11g

  • 802.11n

• Can be bridged with a wired network with switch

• Interconnects wireless clients.