UNIT 02 - The Internet

EXPECTATIONS: Before we start this unit you should be comfortable with the following:

  • the internet began as a series of physical connections between a very few computer servers
  • the internet is now a global network of devices connected by physical wires and remotely such as via radio or microwaves

LEARNING GOALS -- At the conclusion of this unit, I will be able to :

      1. accurately diagram how information gets from one computer to another

      2. Convert binary, octal and hex numbers into decimal values

      3. Convert decimal values into binary, octal and hex values

      4. address challenges involved when developing systems to represent or transmit information

      5. relate specific problems that the internet was designed to solve

        • and suggest how the internet solves those problems

        • and suggest how the internet increases those problems

      6. address how the design of the internet allowed it to grow or evolve

      7. explain who or what is “in charge” of the internet

      8. propose reasonable solutions to resolve dilemmas caused by the structure and continuing growth of the internet

TERMS & CONCEPTS:

Abstraction A simplified representation of something more complex
ASCII American Standard Code for Information Interchange; the universally recognized raw text format that any computer can understand
Bandwidth Transmission capacity (measured by bit rate - See Below)
Binary A way of representing information using only two options.
Bit  A contraction of "Binary Digit"; the single unit of information in a computer, typically represented as a 0 or 1
Bit rate  (sometimes written bitrate) the number of bits that are conveyed or processed per unit of time. e.g. 8 bits/sec.
DNS  Domain Name System: The service that translates URLs to IP addresses. Sort of like how a phonebook let's you translate a person's name into their phone number
Encapsulation "Hiding a packet inside another packet"
HTTP  HyperText Transfer Protocol - the protocol used for transmitting web pages over the Internet
ICANN Internet Corporation for Assigned Names & Numbers formerly a US Government organization, now an independent corporation. ICANN manages the infrastructure of the internet including DNS servers and related activity
IETF  Internet Engineering Task Force - develops and promotes voluntary Internet standards and protocols, in particular the standards that comprise the Internet protocol suite (TCP/IP)
Innovation  A new or improved idea, device, product, etc, or the development thereof
Internet A group of computers and servers that are connected to each other
Internet Service Providers Companies that provide access to the internet for their customers
IPV4 IPV4 (Internet Protocol Version 4 allowed for 32-bit IP Addresses) Only room for just over 4 billion IP Addresses
IPV6 IPV4 (Internet Protocol Version 4 allowed for 32-bit IP Addresses) Now has room for 340,282,366,920,938,000,000,000,000,000,000,000,000 IP Addresses
IP Address A number assigned to any item that is connected to the Internet - Similar to a phone number
Latency  Time it takes for a bit to travel from its sender to its receiver
Net Neutrality  the principle that all Internet traffic should be treated equally by Internet Service Providers.
Network Redundancy  having multiple backups to ensure reliability during cases of high usage or failure
Packets

Small chunks of information that have been carefully formed from larger chunks of information. The four layers we are concerned with are:

1) Application Layer (Where data for the current program live)

2) The TCP (Transmission Control Protocol) Layer Information about which server on the web to connect to and the port on that machine to connect to (amongst other things).

3) The IP (Internet Protocol) Layer. Internet address information lives here.

4) Hardware/Data Layer contains information about the physical packet such as size.
Protocol A set of rules governing the exchange or transmission of data between devices.
Router A type of computer that forwards data across a network
TCP Transmission Control Protocol - provides reliable, ordered, and error-checked delivery of a stream of packets on the internet. TCP is tightly linked with Internet Protocol and usually seen as TCP/IP in writing.
URL  An easy-to-remember address for calling a web page (like www.code.org).
VPN Virtual Private Network

Little Bo Peep Has Lost Her Sheep

and Radar Cannot Find Them

They'll all (face to face)

Meet in parallel Space

Preceding Their Leaders Behind them