Network Devices and Hardware Flashcards
What network device would you use to connect two networks that use different forms/formats of data?
GATEWAY - used to convert data formats and thereby allowing you to connect two, previously incompatible, networks together.
What is the most common type of router found in homes and small offices?
SOHO - small office/home office routers are very common in these places.
What is PoE?
Power (electrical Wattage supplied) over Ethernet (using ethernet cables.
802.3 standards:
802.3AF - 15W
802.3AT - 30W
802.3BT - 60W
What is a punch-down block good for?
Easily and quickly connecting and disconnecting wiring without needing additional connectors (as there are no screws or wire stripping required).
Designed to minimise interference and crosstalk between wires.
Cheap.
What is a patch panel? What is a patch panel made up of? Are they passive or active devices in terms of data filtering/routing over a network?
A patch panel is a passive hardware assembly (switchboard) made up of a combination of punch-down blocks (connector-less) and RJ-45 connectors (ethernet cable connectors).
They are used to connect network computers within a LAN to each other and outside networks (the internet).
They also organise network cables (labelled) and allow for them to be changed/tested easily.
They DON’T actively filter or route data on a network.
What is broadband?
A type of transmission/transfer of multiple different frequencies over a single wire simultaneously (frequency division multiplexing FDM).
This means that TV, phone line and internet data signals can be transmitted simultaneously using the DOCSIS standard of transmission.
DOCSIS - Data Over Cable Service Interface Specification
What is a cable modem? How is it different from a DSL modem? And what does DSL stand for.
A cable modem uses TV wiring (coaxial) to establish a broadband connection (frequency division multiplexing FDM) which allows the device to transmit/receive TV, phoneline and internet simultaneously. (Threaded/screw in F connector).
Whereas, a DSL (Digital Subscriber Line) modem uses Landline/Telephone Lines to connect to ISP (Internet Service Providers). Uses DSL port and filter.
It’s usually ADSL (Asymmetrical Digital Subscriber Line) because the upload and download speeds aren’t the same, hence it has an Asymmetrical bandwidth (maximum rate of data transfer/maximum throughput over a connection)
The closer you are to the telephone exchange the better your ADSL speeds are.
What is the purpose of a modem?
To connect you to an ISP (INTERNET service provider) and give you internet access by converting digital signals into analogue signals that can be sent over phonelines/tv line cables. It links/connects multiple networks together like your LAN and the WAN (Internet).
Often combined with a Router (creates a network between devices on your network)
Modem sends info to the router from the internet which disperses (re-routes/forwards) it to the devices on your home network.
What is bandwidth and is high or low bandwidth preferred?
Bandwidth refers to the maximum rate of data transfer over a connection in a specified timeframe.
Maximal data transfer rate.
High/bigger bandwidth is better.
What is duplex in data transmission/reception?
What is simplex?
Duplex of Full-Duplex means that two connected devices can both transmit and receive data SIMULTANEOUSLY, like TCP. DO ALLL of duplex.
Half-duplex is where they have to TAKE TURNS, e.g. one sends data while the other receives then the other one sends while the first receives, like a walkie-talkie conversation - one person listens while other speaks.
Simplex is where data is ONLY sent, sender sends and receiver receives. One way traffic, like UDP.
What is half-duplex?
Half-duplex is where they have to TAKE TURNS, e.g. one sends data while the other receives then the other one sends while the first receives, like a walkie-talkie conversation - one person listens while other speaks.
Simplex is where data is ONLY sent, sender sends and receiver receives. One way traffic, like UDP.
Duplex of Full-Duplex means that two connected devices can both transmit and receive data SIMULTANEOUSLY, like TCP. DO ALLL of duplex.
What type of Network would you be connecting with an Optical Network Terminal (ONT)?
A fibre optic network.
What is a Demarcation Point used to separate?
A Demarcation Point (DMARC) separates where a customers personal/private network begins and where the service providers (ISP) network ends and vice versa.
Demarcation / Dividing Point of ISP and User Network.
What is a NIC and what is it for?
Network Interface Card - the connection point for a device and a specific network type (e.g. ethernet, WAN, wireless).
They are often built onto the MOBO or added as an expansion card.
There is a specific NIC (Network Interface Card) for each network type.
Cloud Computing
A service sold to clients for cloud computing. Virtually processing data for a fee.
Virtual Infrastructure offered by a cloud provider (company that owns and runs the physical underlying hardware providing the virtual computer services).
What is Software-Defined Networking (SDN)?
Abstracts the control plane (how data is forwarded/routed through the network) from being hardware based to software based so that the network administrator has a lot more control over the network using a centralized interface (management software). It’s also a lot quicker to make configuration changes than manually configuring each device on the network individually.
Transforming physical network devices into virtual planes to manage a network virtually (by using software that performs the roles of networking hardware/devices). Thereby being able to use them in a cloud based infrastructure.
Uses software-based controllers (APIs) to communicate with hardware infrastructure and direct network traffic/control plane (opposed to the traditional model of letting the hardware control the network traffic flows).
Pros of SDN vs traditional model of networking:
-Centralises the data flows through a network using a single server.
-Allows easy abstracted view of the entire network for troubleshooting.
-Can quickly and easily segregate different devices on the network by permissions and quickly quarantine any infected devices.
-Can allocate virtual resources in real time as needed.
-Great for cloud computing and scaling networks.
-No need to worry about compatibility issues from using devices from different vendors.
SDN (Software Defined Networking) is split into 3 layers:
1.Infrastructure layer/data plane
2.Control Plane - send messages back and forth across devices/sends configuration to devices via API’s
3. Management Layer/Management Plane - SSH, API’s
Virtually splits the three layers and abstracts them (simplifies) to manage/segregate/troubleshoot easily.
What is a WAP/AP and what does it do? What advantage does it have over a WiFi range extender (particularly for companies)?
Wireless Access Point/Access Point is a network device that can connect users on wireless devices to the wired internet by converting an ethernet internet connection (usually to a switch or router) into a WLAN (Wireless Local Area Network) and vice verse.
They are often used in businesses to extend Wi-Fi access to a lot of users (up to 60 simultaneously) which is a lot more than a simple Range/WiFi Extender can support. They also allow seamless connection while roaming between WAP’s.
They can also use Power over Ethernet (PoE) thereby not requiring a power line/plug socket nearby.
