Networks amd the internet Flashcards
what is a local area network
a network which consists of a number of computing devices on a single site or in a single businesses
what is a bus topology
where all computers are connected to a single cable. the ends of the cable are plugged into a terminator
advantages of bus topologies
cheaper to install as it requires less cable than a star topology and does not require any additional hardware
disadvantages of bus topology
- if main cable fails, network data can’t be transmitted to any of the nodes
- performance degrades with heavy traffic
- low security as all computers in the network can see all data transmissions
what is a physical star topology
one that has a central node, which may be a switch or computer, which acts as a router to transmit messages
advantages of a star topology
- if one cable fails, only one station is affected, so it’s easier to isolate faults
- consistent performance even when network is being heavily used
- higher transmission speeds give better performance than a bus network
- no problems with collisions as each station has its own cable to the server
- system is more secure as messages are sent directly to the central computer and cannot be intercepted by other stations
- easy to add new stations without disrupting the network
disadvantages of a star topology/network
- may be costly to install because of the length of cable required
- if the central device goes down, network data can no longer be transmitted to any of the nodes
what is the node connected to on a star topology
a central device , typically a switch
what does a switch do
it keeps a record of the unique MAC address of each device on the network and can identify which particular computer on the network it should send the data to
difference between physical and logical topology
- the physical topology of a network is its actual design layout
- the logical topology is the shape of the path the data travels in, and describes how components communicate across the physical topology
how can we make a star topology act like a bus one
- use a bus protocol
- Use a central device that acts as a simple hub instead of a switch
- Ensure that all devices connected to the hub share the same communication medium
- Implement a collision detection and handling mechanism, such as (CSMA/CD), to manage simultaneous data transmissions and collisions,
operation of a physical bus network
- data cannot be simultaneously transmitted in both directions (duplex transmission not possible)
- each station receives all network traffic
- the traffic generated by each station has equal transmission priority
what is an MAC address
an address which is assigned into a card and uniquely identifies a device
- 48 bits long and is written as 13 hex digits
used of mac addresses
tracking people
what is a client server network
- computer networks that use a dedicated computer (server) to store data, manage/provide resources and control user access.