Network topology is the physical configuration of a network that determines how the network's computers are connected. Common configurations include the bus topology, ring topology, and star topology.
 
 1. Bus Network

 

Bus topology is a network setup in which each computer and network device are connected to a single cable or backbone.

Advantages of bus topology

• It works well when you have a small network. 
• Easiest network topology for connecting computers or peripherals in a linear fashion.
• Requires less cable length than a star topology.

Disadvantages of bus topology

• Difficult to identify the problems if the whole network goes down.
• It can be hard to troubleshoot individual device issues.
• Not great for large networks.
• Terminators are required for both ends of the main cable.
• Additional devices slow the network down.
• If a main cable is damaged, the network fails or splits into two.

 

2. Ring Network 

 

Ring network is a computer network configuration where the devices are connected to each other in a circular shape. Each packet is sent around the ring until it reaches its final destination. Ring topologies are used in both local area network (LAN) and wide area network (WAN) setups.

Advantages of ring topology

• All data flows in one direction, reducing the chance of packet collisions.
• A network server is not needed to control network connectivity between each workstation.
• Data can transfer between workstations at high speeds.
• Additional workstations can be added without impacting performance of the network.

Disadvantages of ring topology

• All data being transferred over the network must pass through each workstation on the network, which can make it slower than a star topology.
• The entire network will be impacted if one workstation shuts down.
• The hardware needed to connect each workstation to the network is more expensive than Ethernet cards and hubs/switches.

 

 3. Star Network

Star topology is one of the most common network setups. In this configuration, every node connects to a central network device, like a hub, switch, or computer. The central network device acts as a server and the peripheral devices act as clients.

Advantages of star topology

• Centralized management of the network, through the use of the central computer, hub, or switch.
• Easy to add another computer to the network.
• If one computer on the network fails, the rest of the network continues to function normally.

Disadvantages of star topology

• Can have a higher cost to implement, especially when using a switch or router as the central network device.
• The central network device determines the performance and number of nodes the network can handle.
• If the central computer, hub, or switch fails, the entire network goes down and all computers are disconnected from the network.

sources :  https://www.computerhope.com/ , http://whatis.techtarget.com/definition/network-topology .

Interesting facts you didn’t know about the Internet

1. The well-known social networking website Facebook (founded by Mark Zuckerberg) now has more than 520 million registered users. If Facebook was a country, it would have taken the third place among the world’s largest countries.

 

2. Within a month the Google search engine can handle 35 billion queries. Today, users search almost everything on the net: where to buy a TV, how to find a plumber – 10 years ago it was hard to imagine where a person was looking for answers to these questions.

 

3. The first smiley appeared in 1979, when Kevin McKenzie tried to express his emotions by electronic means. First it look like this -) Three years later, Scott Fahlman added a colon : -) and it took the form we are used to.

 

4. 81% of emails is spam. 

 

5. The most bizarre gadget is a refrigerator with built-in wi-fi, with the help of which you can surf the Internet.

 

6. There are sites out there for people looking for effective suicide instructions.

 

7. In 1974, the word "internet" first appeared in the "Internet Transmission Control Program" booklet as a shortening of the term "internetworking" or "inter-system networking." 

 

8. The first-ever webcam was used to watch a pot of coffee. 

 

sources :  http://www.businessinsider.com/10-crazy-facts-from-internet-history-2013-6/?IR=T#garfield-the-cartoon-cat-once-offered-a-free-email-service-at-gmailcom-1 , https://www.learning-mind.com/10-interesting-facts-you-didnt-know-about-the-internet/