Foundational Networking Tech Flashcards
What is the Access Layer
The layer in Three-Tier Architecture, wiring from Ethernet wall jacks terminate into switches at this layer. In a multi-floor building, each floor may have its own access layer switches.
What is an Ad Hoc Wireless LAN?
An on-demand type of wireless connection where a client connects directly to another client or device w/o having to connect to a Wi-Fi access point or router.
What is an Angled Physical Contact (APC) Connector?
A connector used in fiber optic cabling which has a fiber end face polished at an 8-degree angle. The angled end face causes reflected light to travel at an angle into the cladding, rather than traveling back to the light source.
What is attenuation?
A reduction in the strength of a signal being transmitted. This is a natural consequence of sending signals over long distances, and is the primary reason for distance limitations placed on network cables.
What is a Basic Service Set Identifier (BSSID)?
The unique 48-bit identifier for a single wireless router or access point that follows MAC address conventions.
What is a Bidirectional (BiDi) Transceiver?
A fiber optic module which can simultaneously send and receive data over a single strand by using different light wavelengths for each.
What is a BNC Connector?
A type of connector found on 50 or 75 Ohm coaxial cable. This was commonly found in older thin coaxial cable networks, capable of operating at a speed of 10 Mbps.
What is Carrier-Sense Multiple Access w/ Collision Detection (CSMA/CD)
A set of rules used to detect and avoid data collision on a network. These rules determine how network devices react when they are attempting to simultaneously use a shared data channel, such as in a Shared Media network.
Category 3 (CAT3) cables
Twisted-pair cabling w/ a maximum of 100 Mbps, and a distance limitation of 10 meters
Category 5 (CAT5) cables
Twisted-pair cabling w/ a maximum of 1 Gbps, and a distance limitation of 100 meters
Category 5e (CAT5e) cables
Twisted-pair cabling w/ a maximum of 1 Gbps, and a distance limitation of 100 meters. The wires are more tightly twisted than CAT5, creating less crosstalk interference.
Category 6 (CAT6) cables
Twisted-pair cabling w/ a maximum of 10 Gbps. It has a distance limitation of 100 meters when transmitting at 1 Gbps, or 55 meters when transmitting at 10 Gbps.
Category 6a (CAT6a) cables
Twisted-pair cabling w/ a maximum of 10 Gbps, and a distance limitation of 100 meters. Compared to its predecessor (CAT6), there is more shielding to allow the 10 Gbps transmission rate over a longer distance.
Category 7 (CAT7) cables
Twisted-pair cabling w/ a maximum of 10 Gbps, and a distance limitation of 100 meters. Also has the ability to carry voice, video, and data simultaneously.
Describe the Cisco DNA Center
An appliance that provides a graphical interface and a programming interface for network design, device configuration, network monitoring, and troubleshooting.
What is cladding?
The fiber optic cable layer which surrounds the inner core, made from glass or plastic that is less transparent than the core. The refractive index difference b/t the core and the cladding creates a mirror-like surface which guides the light signal along the core.
Client-Server Architecture
A network architecture model in which a server hosts and manages resources on a network, providing access for clients
Cloud Architecture
A network architecture where resources are stored on a hosted solution and accessed over the public internet. The hosted solution provider is responsible for all costs associated w/ keeping the data center running securely and efficiently, which is one upside to this model
Coaxial Cable
A type of copper cable built w/ metal shielding in order to reduce signal interference, commonly used w/ cable television installations.
Collapsed Core Architecture
A two-tier topology used in smaller networks where the Core and Distribution layers have been consolidated, creating an Access layer and a Collapsed Core layer.
Collapsed Core Layer
The layer in Collapsed Core Architecture which combines the functions of the Three-Tier Architecture Core layer and Distribution layer.
Core (in cabling)
The center of a fiber optic cable used to transfer light signals. Depending on the grade of the cabling this may be made from plastic or glass, w/ plastic cores providing affordability and cable flexibility, and glass cores providing the best performance
Core Layer
The layer in Three-Tier Architecture which interconnects all of the core layer switches. In a multi-building campus, this would be a centralized building which uses multi-layer switches to interconnect distribution layers from all other buildings
Crossover cable
A twisted-pair copper cable that uses a crossed over wire pinout in the RJ-45 connector on each end. The pins designated as the send pins on one end are designated as the receive pins on the other end, and vice versa
Crosstalk
The unwanted signals in a communication channel caused by the transfer of energy from another source.
Customer Edge (CE) Routers
In an MPLS network, these devices sit at the edge of each local network, providing a gateway to the MPLS service provider cloud.
DB-25 Connector
A type of 25-pin connector commonly used for early serial and parallel ports
DB-9 Connector
A type of 9-pin connector commonly used w/ serial ports
Default Route
The route used when more specific info. about a destination IP address is not available, identified by the IPv4 address 0.0.0.0/0 and the IPv6 address ::/0
Distribution Layer
The layer in the Three-Tier Architecture which connects all of the access layer switches. In a multi-floor building, this would be a central point where multilayer switches are used to aggregate access layer switch traffic
EIA/TIA T568B Standard
The most common twisted-pair cable wiring standard used in the networking and telecom industries. There is also a T568A standard, w/ only difference being that pairs 2 and 3 (orange and green) are swapped
Electromagnetic Interference (EMI)
Interference that occurs when radio waves are picked up or radiated by a cable carrying another signal, resulting in signal degradation.
Endpoint
A device that connects to a network in order to utilize resources such as Internet access, file shares, or network printers. Also referred to as a client.
Extended Service Set Identifier (ESSID)
The collection of basic services set identifiers (BSSIDs) that make up a network, representing the primary name associated w/ the wireless LAN. This term is rarely used and represents the same thing as the SSID, which is the preferred term
F-Type Connector
A coaxial connector commonly used for terrestrial television, cable television, and satellite, found on RG-6 and RG-59 coaxial cable
Gigabit Interface Converter (GBIC)
A module used in fiber optic and Ethernet systems as in interface for high-speed networking, w/ a data transfer rate of 1 Gbps
Hypervisor
A software running on a virtual server that is used to create, start, stop, and monitor multiple virtual machines
IEEE 802.3af
The original Power over Ethernet (PoE) standard which provides up to 15.4 Watts of power to a device
IEEE 802.3at
An update to the original Power over Ethernet (PoE) standard which provides up to 25.5 Watts of power to a device
IEEE 802.3bt
The most recent Power over Ethernet (PoE) standard which can provide up to 100 Watts of power to a device
Impedance
The measure of a circuit’s resistance to current flow, represented in Ohms
Infrastructure Wireless LAN
A wireless topology commonly seen in small offices and homes, where a wireless router is connected directly to an Internet Service Provider (ISP) device such as a cable or fiber modem in order to provide wireless clients access to the public Internet