Networking is two or more computers linked together in order to share data, information or resources.
Two basic types of Networking:
LAN
(Local Area Networking) commonly limited or a geographical area, office or home.
WAN
(Wide Area Networking) long-distance connections between remote networks.
Network Devices:
Switch - routing wired traffic between devices, allocating IP addresses and transmitting data only to the intended recipient, not to all connected devices (Hub)
Router - Wired or wireless they have a lot of different roles an capabilities. Primarily they connect your network to a WAN (Internet or VPN).
Firewall - Essential tools that defend your network by securing ports and using rules to filter malicious traffic.
Server - A server is a specific machine used for a purpose such as web, email, print or databases.
Endpoint - The end of a network link. E.g Workstations, servers, laptops and mobiles.
Hub (old tech, a switch without a brain)
Ethernet
A Standard that defines wired connections on a network, defines the way data is formatted over the wire so it is able to be understood at the receiving end.
MAC Address (Media Access Control)
Every network device has a MAC address, a unique identifier from the manufacturer that identifies your device as unique. An example is 00-13-02-1F-58-F5. The first 3 bytes (24 bits) of the address denote the vendor or manufacturer of the physical network interface. No two devices can have the same MAC address in the same local network; otherwise an address conflict occurs.
IP Addresses
An IP address is allocated usually by a device acting as a DHCP server, either a Router, Switch or Independent Server. It allocates all connected devices with a Unique IP Address.
Networking Models
Networking Models exist to facilitate the communication between hardware and software in order to coordinate their activities.
OSI Model
OSI Model (Open Systems Interconnection)
The OSI model divides networked tasks into 7 separate layers. Each layer is part of the chain which Data will travel through from one device to another.
Encapsulation is the process by which a protocol employed in the specific layers adds a header and/or footer (trailer) data. When discussing the Transport, Network, and Data Link layers (2-4), which all typically include some type of header, encapsulation is very crucial.
As the data descends the OSI model from Application to Physical, encapsulation takes place. The header, payload, and footer of the preceding layer are all considered to be the payload of the following layer as data is encased at each descending tier. As we descend the conceptual model, the data unit size grows and the contents continue to envelop.