Networks Flashcards
How can the structure of the internet allow users from other countries access to the website ?
Networks between continents are connected through dedicated connections known as internet back end.
Explain the relationship between the domain name and the IP address?
The domain is registered with the IP address,when a host sends a domain name service request the IP address is returned.
why are websites not addressed purely by their IP address?
This is because humans cant remmeber the IP address of thousands of websites.
what is Packet switching ?
packet switching breaks streams of data into smaller blocks , each sent independently of one another. each node goes into a less congested direction . packets can take different routes to their destination and may arrive out of order.
packet switch is more affordable and efficient than circuit switching as all bandwidth can be used, and it requires less infrastructure.
what is a firewall and describe its role?
A Firewall inspects packets to find the port they are attempting to access through, if the port is blocked, the packet is rejected.
Describe methods used to maintain the security of a network ?
- Proxy server - this enables anonymous surfing
- Anti - virus - Software viruses for entering system
Describe the role of each of the four layers of the IP/TCP stack
Application layer- Network applications are held here
Transport layer - sets up communication between two hosts
Internet layer- uses IP protocol to address and packages data for transmission routes across a network
Link layer - This facilitates the transmission of binary, adds the mac address to the physical network
What is a domain name system (DNS)
The (DNS) maintains a directory of the domain names and translates them into IP(internet Protocol)
what is a Local Area Network? (LAN)
what is a Wide area network? (WAN)
A collection of computing devices, on the same network, which is close together e.g all located in the same building.
A wide area network is a collection of devices on the same network, but far apart from each other
what is an IP address?
a series of numbers that identifies any device on a network. e.g
12.132.259.465
what is a bus topology?
Adv and dis-adv?
A bus topology is an arrangement where nodes are connected in a daisy chain by a single central communications channel.
ADV:
-in-expensive
-devices can be easily added
-good for smaller networks
dis-adv :
-main cable is a point of failure
-poor security
-performance degrades as more devices are added to the network
what is a star topology?
adv and dis-adv?
A star topology is an arrangement where a central node/hub provides a common connection point for all other nodes.
ADV:
-easy to isolate problems
- good performance
-more secure if a switch is used as data is sent only to the recipient
Dis-adv:
-can be expensive to setup
-central device point of failure
what is a physical topology?
what is a logical topology?
The physical topology of a network defines how the devices are physically connected.
The logical topology of a network defines how the devices communicates across the physical topolgiees
what is a Wireless Acess Point (WAP)
this allows devices to connect to the internet , the Wap requires a connection to a router and the router requires a connection to the internet.
what is a protocol?
what is a TCP/IP stack ?
a protocol are a set of rules , that allow two devices to communicate
a protocol that allows only network to communicate with each other
what is a client server model ?
what is a peer to peer model?
A client-server model is when computer communicates with each other through a server, which receive request protocols.
(requires more memory )
a peer to peer model is a decentralised model in which, each party has the same capabilities, data can be accessed without a server,
what is a gateway ?
a gateway is required where data is travelling from one network to another using different protocols
what is circuit switching ?
circuit switching created a temporary and dedicated link of fixed bandwidth between the source and destination, this only lasts until transmission is complete.
with dedicated bandwidth this ensures good quality
what is a client-server network model ?
what are the advantages and disadvantages?
The client server netork is a model where clients share a the service of a common server
best suited in organisations
adv:
easier to manage file security
easier to backup shared data
easier to install software
dis-adv:
can be expensive to set up and maintain
requires IT specialists to maintain
the server is a single point of failure
what is peer to peer model?
ADV and Dis-adv
a peer to peer model are a network of computers that are all equal to each other , where peers serve their own files to each other. these are best suited in smaller organisations where users need fewer access to the same data
adv:
very easy to maintain
no dependency on a single computer
cheap to set up
no expensive hardware
dis-adv:
the network is less secure
users will need to manage their own backup s
list ways in which a system can be prevented from being hacked ?
-proxy
-anti-malware
-encryption
- firewalls
-secure password systems
