Watch Computer Networks Crash Course.
Introduction to Computer Networks
- The internet has revolutionized the way we communicate and access information
- 150 years ago, sending a letter from London to California took 2-3 weeks, but today an email takes a fraction of a second
Early Computer Networks
- The first computer networks appeared in the 1950s and 60s
- They were used within organizations to facilitate the exchange of information and share physical resources
- These early networks were called Local Area Networks (LANs)
Ethernet
- Developed in the early 1970s at Xerox PARC
- Still widely used today
- Uses a shared ethernet cable to connect computers
- Each computer has a unique Media Access Control (MAC) address
- Uses Carrier Sense Multiple Access (CSMA) to manage data transmission
CSMA and Collisions
- When multiple computers try to transmit data at the same time, it causes a collision
- To solve this, computers use Exponential Backoff, which involves waiting for a random period of time before re-transmitting
Network Switches and Collision Domains
- To reduce collisions and improve efficiency, networks can be broken into smaller collision domains using network switches
- Switches keep a list of MAC addresses and only pass data between networks if necessary
Routing
- There are two approaches to routing: Circuit Switching and Message Switching
- Circuit Switching allocates a dedicated communication line for exclusive use
- Message Switching passes messages through multiple stops, using a table to determine where to send the message next
Packet Switching
- Chops up big transmissions into small packets with destination addresses
- Packets are routed through the network using flexible routes with spare capacity
- This approach is decentralized and fault-tolerant
- The internet runs on Packet Switching today
ARPANET and the Internet
- The first packet-switched network was ARPANET, developed in the 1970s
- Today, the internet is a global network of interconnected routers and computers
- It continues to grow rapidly, especially with the advent of IoT devices
Watch Highest Paying Information Technology Careers video.
- The first career is Technology Sales, an entry-level job that can be accessed quickly without a college degree or previous experience.
- Business Development Representative is an entry-level career in technology sales.
- According to Glassdoor, technology sales make approximately $109,000 per year.
- On LinkedIn, there are 85,000 results for entry-level technology sales jobs.
- With experience, technology sales professionals can earn over $220,000 and even over $540,000 per year.
- The second career is Information Security Engineer, which requires at least five years of cybersecurity experience.
- Information Security Engineers oversee an organization’s IT security.
- According to Glassdoor, Information Security Engineers make about $117,000 per year.
- On LinkedIn, there are 17,000 results for entry-level Information Security Engineer jobs.
- The third career is DevOps Engineer, a type of software engineer specializing in getting products to market as fast and efficiently as possible.
- According to Glassdoor, DevOps Engineers make about $131,000 per year.
- On LinkedIn, there are 25,000 results for entry-level DevOps Engineer jobs.
- The fourth career is Software Development Manager, a position that combines software development skills with management skills.
- According to Glassdoor, Software Development Managers make about $213,000 per year.
- On LinkedIn, there are over 8,900 results for Software Development Manager jobs.
- The fifth career is any executive position other than CEO, such as a Chief Technology Officer (CTO) or a Chief Information Officer (CIO).
- According to Glassdoor, CIOs make $298,000 per year.
- The sixth career is a Marketing or Sales Director, a high-level position in a company.
- According to various sources, Marketing or Sales Directors make between $184,000 and $221,000 per year.
- The seventh career is a Tech CEO, which can result in making a ridiculous amount of money, especially in a startup.
- Tech CEOs have more opportunities than CEOs in other industries.
- For instance, Chad Richison of Paycom made $211 million a few years ago, and Elon Musk made $6 billion in money and his net worth increased by $110 billion one year and $90 billion the next year.
LEARNING TARGETS:
- I understand the benefits of computer networks and the concept of Local Area Networks (LANs).
- I can discuss the highest paying Information Technology careers from 2023.