| What is a Computer Network? | Two or more computing devices connected to communicate and share resources. |
| What is a node? | A computing device on a computing network. eg. Phone,Tablet, Laptop, Desktop,Server, Switch,Router etc. |
| What is a client? | Request access to a resource. |
| What is a server? | Provides access to a resource. eg. File server, print server, database server, application server, mail server, web server. |
| Types of Networks (DISTANCE). | LAN, WAN, HAN, PAN, MAN. |
| Characteristics of a Local Area Network. | Connects to two or more nodes
Connects a small geographic area
Connection is: fast(100 mpbs or more), constant, private. |
| Characteristics of a Wide Area Network. | Connects two or more networks.
Covers a large geographic area. eg. Internet.
Connection is: slow(100 mbps or less), occastional, public. |
| Characteristics of a Personal Area Network. | Connects personal devices via bluetooth. |
| Characteristics of a Home Area Network. | Connects devices in a home, typically via Wi-Fi using a wireless router. |
| Two types of Network.(ARCHITECTURE) | Peer 2 Peer, Client/Server |
| Characteristics of a Peer 2 Peer Network. | Computers have mixed roles.
No central authority.(All are equal).
Basic Operating System feature. (Windows 10, Linux, MacOs) |
| Characteristics of a Client/Server. | Computers have dedicated roles.
There is central authority for access and resources.
Advanced Operating System: (Windows 2019,2016,2012,2003), MacOs Server, Linux, Unix |
| Types of Networks(TOPOLOGY). | Bus Topology, Star Topology, Ring Topology, Mesh Topology, Hybrid Topology. |
| Define Bus Topology. | Single cable(Backbone) between two terminators with nodes connected to the backbone. It should be noted that this is hardly used. |
| Advantages of a Bus Topology. | Inexpensive and easy to implement. |
| Disadvantages of a Bus Topology. | Difficult to add, move, change and troubleshoot.
Single point of failure.
Congestion due to broadcasts.
All data is seen by all nodes. |
| Define Ring Topology. | Nodes connected in sequence with each node connected to the previous and the next, with last connected to the first. USED FOR WANS. |
| Advantages of Ring Topology. | Easy and inexpensive to implement
Easy to add, move, change and troubleshoot.
No broadcast. |
| Disadvantages of Ring Topology. | Single point of failure.
All data is seen by all nodes. |
| Define Star Topology. | Central device (eg. Switch) with individual cables connecting each node. USED FOR LAN. |
| Advantages of Star Topology. | Easy to implement.
Easy to add, move, change and troubleshoot.
No cable or node is a single point of failure.
Less congestion.
Data is seen by target node. |
| Disadvantages of Star Topology. | Expensive to Implement.
Central device is a single point of failure. |
| Define Mesh Topology. | Each node connected to each other node. n (n-1)/2. USED FOR LAN. |
| Define Hybrid Topology | A mix of two or more topology. eg. Tree Topology. |
