Common Networking Hardware Devices | CompTIA A+ 220-1001 | 2.2

In this video you will learn about common networking hardware devices such as:  routers, switches, access points, cloud-based network controllers, firewalls, network interface cards, repeaters, hubs, cable/DSL modems, bridges, patch panels, Power over Ethernet (PoE), & Ethernet over Power.

Router

A router is a networking device that forwards data packets between computer networks. Routers perform the traffic directing functions on the internet. Data sent through the internet, such as a web page or email, is in the form of data packets. A packet is typically forwarded from one router to another router through the networks that constitute an internetwork (i.e. the internet) until it reaches its destination node. Devices that are connected to a LAN via a router connected to a cable modem or DLS modem allows for these devices to share a broadband connection to the internet. A router has at least two network connections that use RJ-45 cables.  The port labeled WAN connects the router to a modem. The port labeled LAN connects the router to a switch. If the router has a built-in switch, it has multiple LAN ports numbered starting at 1. Most routers today are wireless routers (use the 802.11 WiFi standards) that combine a router, a switch, and an access point. A router has two IP addresses because it has two network connections.  One network connection uses a private IP address and is used to attach to the LAN (ports numbered 1-4 or higher).  The other network connection is the one used to connect to the internet via a modem. This is a public IP address.

Cisco Networking Router
SOHO Router

Switch

A switch is a high-speed device that receives incoming data packets and redirects them to their destination on a local area network (LAN). Essentially, switches are the traffic cops of a simple local area network. A switch enables direct connections between any two computers or devices on a network. A switch makes a direct connection between the sending and receiving devices by identifying the Media Access Control (MAC) address of each device. Switches are available with as few as four or five RJ-45 ports or with dozens of ports.  Switches can be connected to each other (stacked or daisy-chained) so that a small network can grow without needing to replace existing switches. Most switches support at least Fast Ethernet (100Mbps) signaling, with Gigabit Ethernet (1000Mbps) becoming common in home and small-office networking.  10G Ethernet switches (10Gbps) are now used in enterprise-networks. Low-cost switches used in SOHO networks cannot be configured to perform complex switching functions and are considered unmanaged. A managed switch can organize its switch ports into several logical networks (virtual LANs or VLANs) that cannot interfere with each other which enables different companies or departments to have independent networks in the same physical location to keep their traffic separated. Managed switches also support SNMP for diagnostics & performance measurements. To enable a switched network to connect to the internet, connect a switch to a router.  Many routers made for home or small offices include a multiport switch and a wireless access point.

Network Switch

Wireless Access Point

A wireless access point (WAP or AP) is a networking hardware device that allows other WiFi devices to connect to a wired network based on IEEE 802.11 standards.  The WAP usually connects to a router (via a wired network) as a standalone device, but it can also be an integral component of the router itself.  WAPs act as central connecting points for computers equipped with wireless network adapters by identifying each computer by its MAC address. To connect a wireless network to a wired network, connect the RJ-45 port on the WAP to a switch on a wired network. If the wired network is connected to a router with internet access, the wireless network will also have internet access.

Wireless Access Point

Cloud-Based Network Controller

A cloud-based controller is a tool that transfers data from on-premise to cloud storage. For achieving that purpose, the cloud-based controllers typically use hard disk drives, solid-state drives or a combination of both to store the data on-premises. Cloud-based networking is considered the next generation of computer networks. Cloud-based controllers allow for administrators to manage LANs and branch offices located anywhere on the internet from a centralized location.

Firewall

A firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules.  A firewall typically establishes a barrier between a trusted internal network and untrusted external network, such as the internet. Firewalls can be either software or hardware.  Firewalls are frequently incorporated into wireless routers, Microsoft Windows & mac OS. Software firewalls are also known as host firewalls.

Firewalls work like this:  A computer from outside the network attempts to gain access to a server on the network that has a firewall.  The firewall blocks the incoming traffic from that computer because no computer from inside the network has sent a request to the outside computer.  A computer on the network sends a request to a remote server hosting a website. The remote server responds back to the computer on the network. Because the remote server is responding to a request from the network, the firewall permits the incoming traffic.

Firewall

Network Interface Card

A network interface card (NIC) is a computer hardware component that connects to a LAN. A NIC originally was a circuit board card mounted to the motherboard, but now NICs are built-in interfaces that can connect to a network using cables (via an RJ-45 connector) or wirelessly. The NIC is designed to take communication off the physical cable (or wireless signal from the air) and present it to the computer for processing. The NIC is both a physical layer and data link layer device, as it provides physical access to a networking medium and provides a low-level addressing system through the use of MAC addresses that identifies devices to other hosts on the network. NICs have evolved to also provide wireless and virtual access to networks.

Network Interface Card (NIC)

Repeater/Extender

A repeater/extender is an electronic device that receives a signal and retransmits it. Repeaters are used to extend transmissions so that the signal can cover longer distances or be received on the other side of an obstruction. Wireless signals can be blocked by a variety of objects such as bricks, steel, & concrete walls. Distance can also weaken signals as well. Wireless repeaters can look similar to wireless routers and some even include a switch component, but instead of connecting to a cable or DSL modem, a repeater connects wirelessly to a wireless router.

Network Repeater/Extender

Hub

A hub is a network hardware device for connecting multiple Ethernet devices together and making them act as a single network segment. Hubs were used to connect computers together and to boost the communication signal between computers. It has multiple I/O ports, in which a signal introduced at the input of any port appears at the output of every port except the original incoming. A network hub is considered an unsophisticated device in comparison with a switch. A hub cannot examine or manage any of the traffic that comes through it. A hub has no memory to store data, can handle only one transmission at a time, splits the bandwidth of a connection among all computers connected to it, and broadcasts data to all computers connected to it. When it comes to the splitting of bandwidth, a five-port 10/100 Ethernet hub will divide the 100Mbps speed of the Fast Ethernet amongst the five ports, therefore only providing 20Mbps of bandwidth to each port for Fast Ethernet. With that being said, hubs have become rare in networks.

Networking Hub

Modems:  Dial-Up, Cable, and DSL

A modem (modulator/demodulator) is a hardware device that converts data into a format suitable for a transmission medium so that it can be transmitted from one computer to another (historically along telephone wires). A modem modulates one or more carrier wave signals to encode digital information for transmission and demodulates signals to decode the transmitted information. The goal is to produce a signal that can be transmitted easily and decoded reliably to reproduce the original digital data. Modems connect a LAN to an ISP. Dial-up modems allow computers to gain access to the internet by converting the computer’s digital signals to analog signals used by a land-based phone line. The issue with dial-up modems is that they are slow devices and are typically used if no other internet option is available. The most common modems in use today are cable & DSL modems.

Typical Cable Modem

Wireless Bridge

A wireless bridge (or a setting on many access points) connects two wired networks together over WiFi. The wireless bridge acts as a client, logging in to the primary router and getting an internet connection, which it passes on to the devices connected to its LAN.

Patch Panel

A patch panel is a device or unit featuring a number of jacks, usually of the same or similar type, for the use of connecting and routing circuits for monitoring, interconnecting, and testing circuits in a convenient, flexible manner. Patch panels are typically built into a wiring closet or added to equipment racks. Patch panels are primarily designed as a termination point for twisted pair (TP) & fiber cables used in networks.

Typical Patch Panel

Twisted pair cabling is a type of wiring in which 2 conductors of a single circuit are twisted together for the purposes of improving electromagnetic compatibility. Compared to a single conductor or an untwisted balanced pair, a twisted pair reduces electromagnetic radiation from the pair and crosstalk between neighboring pairs and improves rejection of external electromagnetic interference. TP cables must be untwisted before being punched into the appropriate connection on the back of a patch panel. TP cables are color coded to allow for the proper termination of the cables. The most common standards for color-coding are known as T568A (straight-thru) or T568B (cross-over). The front of the patch panel uses RJ-45 connectors for short standard network cables.

RJ-45 Pinout

Ethernet over Powerlines

Powerline networking is a technology that sits between wired and wireless. Ethernet over powerlines uses the existing electrical wiring in a home or office to transmit network data. This can be a practical solution when there is a need to extend a wired or wireless internet connection. Ethernet over powerlines provides powerline adapters that are sold in pairs: one unit for the AC wall socket which is connected to the router via a switch, and the other adapter plugs into an AC wall socket in a room that needs network access.

Network Powerline Adapter

Power over Ethernet

Power over Ethernet (PoE) describes any of several standard or ad hoc systems (or switches) that pass electric power along with data on twisted pair Ethernet cabling. This allows a single cable to provide both data connection and electric power to devices such as wireless access points, IP cameras, routers, VoIP phones, and other Ethernet devices. The PoE switch can send up to 25.5 watts of power on CAT5 or greater grades of unused twisted pairs (pins 4-5, 7-8) or by using all four wire pairs, which allows for it to be used with Gigabit Ethernet. Another type of PoE device, known as a power over Ethernet injector, is installed between a standard Ethernet switch and a PoE device to provide power only.