Networks - Year 10
Terms in this set (32)
2 or more computers connected to each other.
Advantages of Networks
-It allows communications between workers.
-It allows data to be shared.
-It allows peripherals to be shared.
-It allows computers to be upgraded more easily.
- Local Area Network
- Located on one site
- Owner of network owns the infrastructure
- Wide Area Network
- Covers a large geographical area - may be worldwide
- Infrastructure may be provided by telecoms companies
Network Interface Card
- Each node needs a NIC to connect to the LAN.
- Has a unique MAC address
- A device that connects nodes together.
- Makes them act as a single segment.
- Not smart - all data packets are transmitted.
- Cheap devices - USB hubs useful in home computer installations.
-A switch is an intelligent hub. It can split the network up into segments and reduce collisions.
- The switch looks at the Mac address destination for the packet and sends it directly to that node
Peer to Peer Network
-All computers are equal
-Tend to be slow
-Suitable when a small network
-Security is up to each user
-Has a designated server. The nodes are clients and make requests to access files or programs from the server.
-The server is a powerful machine typically with more memory that can serve the needs of the clients.
-Different servers may be responsible for different tasks. You may have the following servers: print, web, file, mail
-Handles the security (logins), backup and installation of software
Domain Name System (DNS )
Translates domain names into IP addresses
File Transfer Protocol
For transferring Files
Hyper Text Transfer Protocol (HTTP)
For displaying web pages
IMAP and POP3
For accessing emails
For text communications on a network
-An Internet Protocol (IP) address is a unique 32-bit reference number that is allocated to devices on a computer network that uses the Internet Protocol.
-Set by the software
-It is a unique 48 bit number stored in the NIC so it can identify a device on a network.
-Set by the hardware
A small piece of data.
IP address of the sender and the destination, the sequence number, the data and a check sum which allows them to be checked for accuracy
Data packets sent through a network taking different routes.
Packets are reassembled on receiving computer
-Levels of Access
-User Names and Passwords
Levels of Access
Each user can only access the files they need. Prevents accidental damage to files.
-Contain letters and numbers (upper and lowercase)
-use other characters
-hard to guess
Transforms the message so that it cannot be understood except by someone who has the correct key.
Prevents hacking/unauthorised access to the network
Anti Virus Software
If users bring in their portable storage devices or download files/email attachments Software will scan for viruses
Policies that users must follow. E.g:
An acceptable use policy that users must follow. i.e. not use unauthorised programs, using at certain hours, not downloading programs
Disaster Recovery Plan
A written plan which identifies:
-how to prevent data loss,
-How to detect it
-How to recover from any data loss
-Who is responsible for the recovery
Making a copy of the original files. Need to consider:
-How often to backup
-What medium to use
-Where it will be kept
This when software will detect if there is a potential threat or disaster and will immediately switch to a backup/duplicate system. This will stop any interruptions to the network
When data that is no longer in regular use is stored somewhere else in case it is needed one day