Network Basics Flashcards
Host
A node that serves as the beginning or ending point of the communication.
Physical Network
A network of interface cards, network hardware, cables, and so on that you can see when you look around a building.
Logical Network
A virtual representation of a network that appears to the user as an entirely separate and self-contained network even though it might physically be only a portion of a larger network or a local area network.
Repeater
It allows a network cabling system to extend beyond its maximum allowed length and reduces distortion by amplifying or regenerating network signals.
Hub
A simple network device that lets you connect multiple nodes in a star configuration.
Bridge
A device that actively works to prevent collisions by making sure not to send data to a segment that’s already busy.
Translating Bridge
A device which joins segments using different link layer protocols, by translating frames from one format into the other, such as from Ethernet to Token Ring or Wi-Fi.
Digital Subscriber Line (DSL)
A family of related technologies which carry data as a separate, high-frequency signal over the same physical cables of a voice telephone or ISDN line, without interfering with the telephone service.
Node
Any device on the network that actively transmits and receives information. This could be a computer, a networked resource like a printer or storage device, or a network device like a switch or router.
Media
The physical path connecting the nodes. Most commonly media is either copper cables, fiber-optic cables, or radio transceivers, but anything that can carry information can be a network medium.
Data
The information carried by the media. Usually, data is digitally encoded in an electrical, optical, or radio signal.
Networking device
A node that functions as part of the network structure rather than as a host or resource.
Networking challenges - Availability
The ability of a network to maintain connectivity as consistently as possible, while avoiding outages. A broken connection is an example of reliability failure.
Networking challenges - Reliability
Not to be confused with availability, in network terms reliability means that the network is free of communication errors: every packet of data successfully arrives at its destination with its contents intact and unaltered.
Networking challenges - Serviceability
How easy it is to perform maintenance on a network, whether that means replacing cables, accessing network devices, or configuring network software.
Networking challenges - Performance
The network’s ability to rapidly convey traffic.
Networking challenges - Security
How hard it is for unauthorized users to access data on the network.
Networking challenges - Scalability
The network’s ability to grow to meet new demands.
Networking challenges - Compatibility
The ability of all of a network’s components to communicate successfully both physically and logically.
Networking challenges - Quality of Service (QoS)
The ability of a network to provide better service and connection quality to special kinds of network traffic.
What three conditions are needed to establish connectivity?
A physical connection must exist, the sender must be able to convey information to the recipient, and the recipient must be able to understand and act on it.
What is the difference between availability and reliability?
Availability is how seldom network outages occur, while reliability is how consistently the network ensures every packet reaches its destination intact.
Local Area Network (LAN)
A Local Area Network (LAN) is confined to a fairly small area, usually within a single building. Today you can find LANs wherever you go.
Wide Area Network (WAN)
A Wide Area Network (WAN) extends over a very large area, with nodes in multiple cities or countries. The Internet is the most familiar example of a WAN, but not the only one.
Personal area network (PAN)
personal area network (PAN), which covers only a very small area, of centimeters to a few meters across. Usually, a PAN is confined to a particular user’s devices, such as a computer and its peripherals.
Near Field Communication (NFC)
Near Field Communication (NFC) is used for short-distance communications between smartphones or other personal devices.
Campus Area Network (CAN)
Used to connect multiple buildings in a single campus
Metropolitan Area Network (MAN)
Used to connect all or part of a city
storage area network (SAN)
Used to connect computers to storage devices using network technology
What connection technologies are most common for modern LANs?
Ethernet for wired connections, and Wi-Fi for wireless networks.
Other than physical distance, what distinguishes a WAN from a LAN?
a WAN requires transmission technologies compatible with long distances, and usually involves leased lines owned by a third party.
peer-to-peer
In peer-to-peer, there is no central administration. Every host connects to the network as an equal, or peer, and can offer its own resources to the network.
client-server
In client-server, hosts are divided into two categories: the clients that request resources, and the servers that provide them. To access a network resource, a client requests it from the server.