Internet & Telecommunications: Intro

Introduction to the Internet and Telecommunications

• The Internet enables communication with servers across the globe in a fraction of a second.
• Understanding how the Internet and networks function helps with creating new products and services.
• Crucial for:
  • Marketing professionals
  • Finance firms
  • Understanding global trends in emerging markets
• Network downtime can effectively halt operations for most businesses.
• Managers must understand how the Internet works to secure their firms and maintain constant connectivity.

Internet 101: Understanding How the Internet Works

• To communicate with another computer on the Internet, your computer needs to answer the following:
  • What are you looking for?
  • Where is it?
  • How do we get there?
• The computers and software that comprise Internet infrastructure can provide these answers.
• The Internet constitutes a network of millions of interconnected networks.
• Connection to the Internet is facilitated through an Internet service provider (ISP).
• Most ISPs come in the form of big telecommunications companies.
• The Internet is decentralized, lacking a central authority or owner.
• Key features of the Internet's design include redundancy and fault tolerance for reliability.

The URL: What Are You Looking For?

• The uniform resource locator (URL), also known as the Web address, indicates what the browser is looking for.
• URLs beginning with "https" use Secure Sockets Layer (SSL) for encrypted communication between the browser and server for security.
• https ensures safe transmission between endpoints, but this doesn't guarantee site validity against impersonation.
• The hypertext transfer protocol (http) and https define communication rules for web browsing.
• A protocol is a set of rules for communication.
• The Internet supports varied applications with different application transfer protocols.
• FTP (file transfer protocol) is used for file transfers such as website updates.
• SSL (Secure Sockets Layer) encrypts Web transmissions for secure communication.
• The hypertext markup language (HTML) is used to create and format web pages
• File names and paths are case-sensitive, amazon.com/books differs from amazon.com/BOOKS.

Host and Domain Names

• The domain name signifies the network, while the host indicates a specific computer within that network.
• Some domains have multiple hosts such as for Google, websites are served from several computers at a given host name for ensuring load balancing and fault tolerance
• Subdomains can represent smaller networks within an organization or reflect URL practices such as for international URLs

Getting Your Own Domain

• Domain names are obtained through registrars by paying for the right to use the name for a period of time.
• Registrars get accreditation from ICANN (Internet Corporation for Assigned Names and Numbers).
• Top-level domains include generic (gTLDs such as ".com" and ".org") and country code (ccTLDs like ".uk").
• Sponsored top-level domains (sTLDs) are restricted.
• Some domain names, but not all, are legally restricted
• Domain name registration proceeds on a first-come, first-served basis.
• Trading in domain names has become potentially lucrative, but also illegal if done to profit from a known trademark.
• The practice of cybersquatting knowingly registers a domain to profit from another firm's trademark or name and is illegal
• Geographic TLDs do not have the same two-character restriction as country codes.
• The United States has passed that Anticybersquatting Consumer Protection Act (ACPA).

IP Addresses and the Domain Name System: "Where Is It? And How Do We Get There?"

• Every device connected to the Internet has a unique identifying IP (Internet protocol) address.
• These addresses are assigned by the connecting organization, like a university or an ISP.
• IP addresses can be used to determine a user’s location for search customization and advertising.
• The still widely used format for IP addresses is expressed known as IPv4.
• Shortage of IPv4 addresses is being addressed by IPv6, expanding address space.
• IPv6 increases possible address space to a theoretical limit of 2^128 addresses.
• A technique known as NAT (network address translation) allows multiple gateway devices to use a single IP address.
• Conversion to IPv6 is slow due to backward incompatibility with IPv4; although, most modern hardware and operating systems now support IPv6.
• Services such as Facebook, Google, and Microsoft are now mostly IPv6 accessible.
• Amazon’s AWS now offers IPv4 addresses commercially for a fee.
• The domain name service (DNS) maps host/domain names to IP addresses.
• Computers use DNS resolvers to find IP addresses by contacting nameservers in a hierarchical system.
• Caching improves efficiency by storing previously looked-up addresses; these are periodically refreshed for data accuracy.
• The DNS structure is designed to be fault-tolerant as alternative exact copies exist and the system is smart enough to move on if others fail.
• Hacked DNS servers pose a threat by redirecting users to malicious websites.
• DNS cache poisoning can redirect users to unintended sites by exploiting DNS software holes
• Software updates, and general "cyber hygiene" is necessary to prevent attacks and other forms of hacking