11. Standards and Protocols

• What is a protocol?

  A standard for communication , they set the rules for how signals are sent through network connections
• What is ethernet?

  A standard for connecting computers to a network using a cable
• Pros and cons of ethernet?

  Pros: High speed, reliable, widely available, secure. Cons: Requires physical connection, limited mobility, potential for interference.
• What is Wi-Fi?

  A standard for sending and receiving wireless signals.
• If a device uses Wi-Fi standard it can pick up a network signal in any Wi-Fi hotspot. Almost all wireless devices can do this
• Pros and cons of Wi-Fi?


  Users can move around freely.-Easier to set up , less expensive-Convenient to use.-Can handle large numbers of users.-Transfer of info to social media is much easier

  Cons

  -Signals can be obstructed.-Less secure than wired networks.-Speeds slower than wired networks.-Relies on signal strength to wireless access point
• What is bluetooth?

  A standard for communication with devices that are nearby
• Pros and cons of bluetooth?

  Very low power consumptionVery short range , around 10 metres
• What is a standard and why do we need them?

  A set of specifications for hardware,softwareWithout them most devices would not be able to successfully interact or communicate
• Name the 4 internet protocols?


  TCP/IP

  HTTP

  HTTPS

  FTP
• What is the role of TCP/IP protocol?


  Transmission Control Protocol / Internet protocol

  
  

  Sets out the rules devices must follow when communicating with each other over a network

  
  

  It also plays an important role in packet switching (TCP), and routing of packets on a Wide Area Network (IP).
• What is the role of HTTP?

  Hyper text transfer protocol

  Client server method of requesting and delivering HTML web pages
• What is the role of HTTPS?

  Hyper text transfer protocol secure

  Encryption and authentication for requesting and delivering HTML web pages.Used when sensitive info needs to be transferred such as when users log into their online banking accounts.
• What is FTP?


  File transfer protocol

  Lets us send files from computer to computer in a client-server network
• Name the 3 email protocols?

  POP

  IMAP

  SMTP
• What is the role of POP?

  Post office protocol

  Moves our emails from an email server onto our own computer
• What is the role of IMAP?

  Internet message access protocol

  A more modern email protocol ; lets us look at our emails on an internet page
• What is the role of SMTP?

  Simple mail transfer protocol

  Sends email messages to other computers
• When a message is sent through the internet , it has to use many protocols. The different protocol signals are added to the message before it is sent. They are stacked on top of each other in layers

  The message is passed from computer to computer on an internet journey. When the message gets to its destination the layers of protocol are removed in reverse order
• What are layers?

  Divide the complex task of networking into smaller,simpler tasks that work with each other
• Give 3 advantages of layers?

  Reduces complexity of the problem into manageable sub-problemsDevices can be manufactured to operate at a particular layerProducts from different vendors will work together
• Describe the steps taken in displaying a web page (5)?

  1. Domain name is typed into the address bar of a browser2) A query is sent to the local DNS server for the corresponding IP 5) Browser connects IP address of server and access web site
  2. 4)If local DNS server does not hold the IP address the query is passed to another DNS server at high level until IP Address is reoslved. Once found address is passed on to DNS server lower in hierarchy until passed to your local DNS server and browser5) Browser connects IP address of server and access web site