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Network protocols - Coggle Diagram

- - - - To send data over a network the TCP protocol:
        Divides the message into smaller data packets
        Adds a sequence number to each packet so that it can be reassembled after delivery
        Adds error correction information so that errors can be spotted and fixed
        
        To receive data over a network the TCP protocol:
        Examines each packet for errors
        Fixes any errors (if possible) or requests that the packet be resent
        Spots missing packets, requesting any be resent
        Uses the sequence number of each packet to reassemble the message
        
        When data is sent over a network, the Internet Protocol (IP) is responsible for:
        Adding the destination address to each data packet
        Adding its own address (source address) to indicate where the packet originated from
        
        When data is received over a network, the Internet Protocol (IP) is responsible for:
        Accepting data packets which have its own address attached
        Ignoring all data packets that do not contain its own address
- - - - You can tell when the HTTPs protocol is being used as you will see it displayed as part of the webpage URL
        Also, you will see a small padlock symbol displayed either next to the URL or in the bottom right-hand corner of your web browser.
- - - - Post Office Protocol (POP) is used to receive emails from a remote server. They are downloaded to a local email client and are viewed offline.
        
        The issues with POP are that:
        It can only handle one mailbox
        Messages, once downloaded from the server, are deleted. They are no longer available to view via other devices.
        It does not support complex searches of emails on the server.
    - - Internet Message Access Protocol (IMAP) also enables emails to be downloaded from the server, to the client device.
        However, unlike POP, the email can be set to remain on the server after being downloaded.
        
        This means that you can use multiple devices to view the email.
        So you can access an email message multiple times, from different locations, using different devices i.e. laptop, phone, tablet etc.
        
        IMAP allows you to set flags on emails indicating whether they have been read, replied to, need attention etc
        Unlike POP, It allows complex searches to be carried out based on subject, sender, date etc
        Unlike POP, It can handle more than one mail box.
    - - Simple Mail Transport Protocol (SMTP) is the protocol used for sending emails across the internet.
        It is used by the client to send emails to a server.
        It is also used between servers to push an email from one server to another.