Networking

Networking

1. Topology Types

   • Star
     • All the clients are connected to a hub or central server
   • Ring
     • A series of computers connected to each other only in a ring
   • Mesh
     • All the clients are connected to each other directly and don't have to pass through another computer
     • Path-finding
   • Bus
     • All clients are connected to a single wire or connection

2. LAN

   • Local Area Network
     • All the clients on the private side of a firewall

3. WAN

   • Wide Area Network
     • A series of LANs connected e.g the internet or a business server

4. Protocols

   • Examples
     • IMAP
       • Replaced POP3 , this allowed emails to be read without the mail being read
     • HTTPS/HTTP
       • A standard protocol used to request a HTML file from a web server
     • FTP
       • a protocol for transferring files between computers
     • POP3
       • (post office protocol 3) Used to download emails from a mail server
     • SMTP
       • used for uploading email to a server
     • TCIP/IP
       • Application layer, Transport layer, Network layer, Data link layer, Physical layer
       • used as single protocol is too complex to carry out
       • IP addresses and DNS
         • IPv4
           • has run out. There are more than 4.2 billion devices on the internet not enough for each device
         • IPv6
           • IPv6 uses 128 bit (2 to the power of 128)
         • DNS
           • puts a name to an IP address so that numbers don't have to be remembered eg : asdasd.co.eg
   • a set of agreed rules that both sides of a communication channel follow