Connecting to the Internet

The penultimate module in this second course was based on the different technologies that are used to connect to the Internet. The aims of this module were to cover the following objectives:

• To describe various Internet connectivity technologies
• To define components of WAN's
• To outline basics of wireless and cellular networking

The first of the connectivity technologies I learnt was POTS and Dial Up, using the plain old telephone service for data transfer, establishing connections by dialling a phone number. However, we have since moved on from this technology to using broadband. This technology itself has also evolved over time, giving us T-carrier technologies, digital subscriber lines, on to cable broadband and finally fibre connections. These fibre optic connections use light for data transfer, allowing much faster speeds over much larger distances!

I also learnt about wide area networks, the basic components and how they spread across

physical locations, linked across the Internet via an ISP. However, with the use of point to point VPN's nowadays, VPN tunnels can be established directly between sites using cloud services, eliminating the need to have WAN technology. 

Next I learnt about wireless networking technologies, being introduced to WiFi, which uses radio waves in the frequency bands 2.4Ghz & 5Ghz to transfer data. WiFi is defined by IEEE 802.11 standards and data is sent in an 802.11 frame, of which I took a closer look at, dissecting each field that makes one up. I also learnt about different wireless network configurations and how wireless channels can be used to help address collision domains and resolve connectivity issues.

I then explored ways in which wireless networking is secured using encryption technologies like WEP and WPA2, as well as MAC filtering; allowing only specific MAC addresses to make connections to access points. A final consideration was also given to cellular networking and how mobile devices use a combination of cellular, WiFi and Bluetooth technologies to get connected.

This module was quite short but equally important to grasp the concept of how devices connect to the Internet in different ways. I'm looking forward to getting the last module of this course completed and on to the next one!

Dave