Introduction to Computer Networking - What Internet Conenction is Right for You?

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• Introduction to Computer Networking
• What Internet Connection is Right for You?

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What is Bandwidth?
Bandwidth is a measurement of the data
transmission capacity of a network connection. It
explains how much data (information) can be sent
or received over a certain amount of time.
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Bits and Bytes
A bit is a binary number - either a zero or a
one. It is the smallest unit of data. A byte is
a collection of eight bits.
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How is bandwidth and storage capacity measured?
bit a 1 or a 0 - abbreviated as a lowercase b Byte 8 bits - abbreviated as an uppercase B
bits/second (bps) are used to describe network speeds
Bandwidth Measurements 1 Kilobit per second
(Kbps) 1,000 bits per second (bps) 1 Megabit
per second (Mbps) 1,000 Kbps 1 Gigabit per
second (Gbps) 1,000 Mbps
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Data Prefixes
You can add a prefix to illustrate a higher
amount of bits or bytes. It works just like the
Metric system - ex. 1000 meters 1
Kilometer 1000 bytes can be written as 1
Kilobyte, or 1 KB for short
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Upload Bandwidth vs. Download Bandwidth

• Download bandwidth is the speed at which you can
  receive data from the internet
• Examples of activities that involve download
  speeds are
• Streaming videos
• Downloading files
• Browsing websites
• Upload bandwidth is the speed at which you can
  send data to the internet
• Examples of activities that involve upload speeds
  are
• Video Conferencing
• Emailing a large attachment to your coworker
• Backing up files from your computer to cloud
  storage

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Asymmetrical vs Symmetrical Bandwidth
Symmetric Bandwidth

• Symmetrical internet connections offer the same
  bandwidth for both downloading and uploading
• Examples are Fiber and Ethernet
• Allow you to do everything fast, whether you're
  getting information from the internet or sending
  information out
• Asymmetrical internet connections have different
  bandwidths for downloading and uploading
• Examples are Cable, DSL, and Cellular
• Asymmetrical connections can be frustrating when
  you need to upload large files or participate in
  video conference

Down
Up
Asymmetric Bandwidth
Down
Up
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Comparison of Internet Connection Technologies
Not all internet connections are the same!

• Fiber is the best option available, with high
  download and upload speeds
• Cable has fast download speeds, but it has slow
  upload speeds
• DSL and Cellular are much slower and should be
  avoided if possible

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Common Download Bandwidth Usage Examples
Every activity online consumes bandwidth, and all
activities benefit from higher bandwidth. For
reference, Heres how much bandwidth is needed
for some common activities online.
This data was provided by the FCC Broadband Speed
Guide
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Internet Traffic Over Time
Traffic on the internet continues to grow, year
by year
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What is Network Latency?

• Latency is the measurement of the time data takes
  to travel from sender to receiver
• High latency can manifest itself in the form of
  lag - a delay when on a video conference, or a
  frustrating stutter when playing an online game
• Latency is measured in milliseconds and it always
  increases with distance
• Some network technologies have higher latencies
  than others
• The FCC defines broadband as having less than 100
  ms of latency

Satellite - 26,000 Miles
Fiber - 100 Miles
Your Computer
Server
Fiber - 1000 Miles
300 ms
1 ms
10 ms
In this example we see a high latency of 311 ms
due to the distance a geosynchronous satellite is
from the Earth
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Comparison of Internet Connectivity Technologies
Technology Speed Reliability Symmetric Speeds
Fiber Highest Highest Yes
Cable (Coax) High High No
DSL (Phone Lines) Low High No
Cellular Medium Medium No
Fixed Wireless High Medium Yes
Satellite Low Medium No
Satellite
Cellular
Fiber
DSL
Cable
Fixed Wireless
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Wired vs. Wireless Network Connections
Wired Wireless
Reliability High reliability Mid reliability
Speed High speed Mid speed
Mobility Tethered to a cable Completely Mobile
Security Higher, Hackers require physical access Mid, Hackers just need to be in range of a signal
Price Mid Low
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Whats your bandwidth and latency?

• You can test it now with these tools!
• M-Lab
• FCC Speed Test App
• Speedtest.net