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Physical network connections
The Internet is a network of computers connected to each other. But what does each physical connection look like? It depends on the needs of the connection and the size of the network.
Copper cables
Since the landline telephone system originally used copper wires, the first Internet connections reused that technology and many still use it today.
If you're in a computer lab or near a modem, you can probably find a cable similar to this one:
That's a CAT5 cable, a type of twisted pair cable that's designed for use in computer networks.
If you were to look inside the cable, you would find four twisted pairs of copper wires:
Twisted pair cables send data through a network by transmitting pulses of electricity that represent binary data:
To make sure cables are transmitting information in a way that can be understood by the recipient, they follow the Ethernet standards. That's why twisted pair cables are commonly known as Ethernet cables.
They are used both in networks as small as a company office (a LAN) or as large as an entire country (a WAN).
Fiber-optic cables
A fiber-optic cable contains an optical fiber that can carry light (instead of electricity). The fiber is coated with plastic layers and sheathed in a protective tube to protect it from the environment.
Fiber-optic cables communicate by sending pulses of light that represent binary data:
They typically also follow the Ethernet standards to make sure they're sending data in a way that can be commonly understood by any recipient in the network.
Fiber-optic cables are capable of transmitting much more data per second than copper cables. They're often used to connect networks across oceans so that data can travel quickly around the world.
As fiber-optic cables become less expensive, they're becoming increasingly common in city-wide networks as well.
Wireless
Wireless connections don't involve any wiring at all—at least at first. A wireless card inside the computer turns binary data into radio waves and transmits them through the air:
Those radio waves can't travel very far: 75-100 feet in a place like an office building that's filled with all sorts of obstacles, or up to 1000 feet in a wide open field.
The waves are hopefully picked up by a wireless access point which converts them from radio waves back into binary data. Wireless access points are connected to the rest of the network using physical wiring, like copper or fiber-optic cables.
Wireless connections are limited in how much area they can cover, but they are increasingly commonplace due to the prevalent use of portable computing devices.
All together now
At any given time, our Internet connection might be using a combination of those technologies. Maybe we're using WiFi to connect to our home router, our home router is using twisted pair copper cables to connect to the metropolitan network, and those cables are hopping over fiber to communicate with overseas data centers.
Each technology has both advantages and disadvantages, so we use whatever is best for the job.
Type | Sends | Distance | Bandwidth | Issues |
---|---|---|---|---|
Wireless | Radio | 100 ft | 1.3 Gbps | Slower in reality |
Twisted pair copper cables | Electricity | 330 ft | 1 Gbps | Susceptible to interference |
Fiber-optic cable | Light | 50 miles | 26 Tbps | Expensive |
The data in that table is current as of early 2020. Engineers are constantly discovering new ways to improve network connections, especially when it comes to increasing the bandwidth. We'll learn more about bandwidth in the next article on bit rate, bandwidth, and latency.
🙋🏽🙋🏻♀️🙋🏿♂️Do you have any questions about this topic? We'd love to answer—just ask in the questions area below!
Want to join the conversation?
- What's the main difference between a WAP and a router?(15 votes)
- I dont know what were talking about bud(2 votes)
- Why I saw internet wire in the ocean. Internet wire passing signal through the ocean. Is it true?How? Can you explain me little bit?(5 votes)
- For now, 98% of our oversea data are transmitted using Submarine communication cables. The reason why satellites aren't used is due to distance and speed. Using undersea cables is cheaper, faster, and more efficient. Humans have started placing cables like this for over a 100 years! The cables now are Optical fiber cables that are placed by cable laying vessels. The cables have several layers of protection to make sure it can last at least 25 years. When it breaks due to earthquakes, sharks, and human activities; cable ships are sent to repair them. We have around 550,000 miles (885,139.2 kilometers) of fiber optic communications cables in the sea right now!
Source: Educational kid's magazine.(27 votes)
- How do wireless signal amplifiers work?(2 votes)
- The general idea is that you have a middle point that repeats the signal. So say you want to tell someone across a football stadium something without moving. You can't yell loud enough, so you place a couple of people between yourself and the recipient and have them yell what they hear. So you yell "hello", the next person to you repeats it and so on until it reaches the target.(27 votes)
- What if we created a computer that ran on light instead of electricity?(2 votes)
- The internet would become more inefficient because the sun keeps getting further away. This wouldn't be too noticeable for a while, but eventually it would.(0 votes)
- Hey! So for people who use data plans (LTE, 5G etc), do they access the internet via a local router and bypass the password needed or like via a radio tower, or how does it work?(3 votes)
- Internet via data plans comes from a network of cell phones towers. The cellular network is different from a WiFi network because of the radio frequency used. Wifi has a short range vs cellular's much (usually) longer range. That's the basics but LTE and 5G are a bit different in terms of technology used. I hope that answers your question(6 votes)
- must a wireless access point connect to a network with physical wiring before it can work?(2 votes)
- Yes, a wireless access point is usually connected to a wired router and creates a WLAN (wireless local area network) so other devices can connect to the internet.(7 votes)
- Is 50 miles the furthest that a single run of fiber can go (single mode or multi mode)? For some reason I thought it could go further.(2 votes)
- Kendra,
According to a British company called Black Box, single mode fiber can reach about 40 km. This aligns (to the best of my memory) with the TestOut training materials I used in preparation for the Network+ certification. 50 miles is quite an overestimate.
Keep in mind just because a single run can only go so far doesn't mean a network of fiber cables can't cover as much as you can fund.
Hope this helps,
Hunter(6 votes)
- How does a router know where to send the packet without knowing how to get to the destination?(3 votes)
- Routing Protocols! The idea is similar to dropping off mail. As users, we drop off mail to the post office and how it reaches our final destination is unknown to us. The post office has internal protocols/techniques to get our messages to our final destinations (via trains, cars, flights etc)
https://www.khanacademy.org/computing/computers-and-internet/xcae6f4a7ff015e7d:the-internet/xcae6f4a7ff015e7d:routing-with-redundancy/a/internet-routing
Hope this helps!(4 votes)
- which one is faster than the rest?(3 votes)
- Fiber-optic is fastest as it can send data at the speed of light. Machines can't send nor receive data that fast however, so it isn't that fast in reality.(4 votes)
- Why is the CAT5 cable called a CAT5 when there are only 4 twisted wires inside?(4 votes)