Lesson 7 - Chapter 1: How the Internet Works Flashcards
What makes up the Internet’s infrastructure?
Networks that are divided into 3 tiers (1-3) depending on how important they are to the Internet’s operation
(Not LANs)
What do a small number of Tier 1 providers own and charge lower-level networks to use?
they own the long-distance high-speed fiber-optic backbone networks that interconnect Earth’s major cities at special NAPs
What does NAP stand for?
Network Access Points
What are backbone networks?
the ones that interconnect Earth’s major cities (through high-speed fiber-optic networks)
Most of the regional ISPs with names the public will recognize are what Tier?
Tier 2
What type of providers operate at Tier 3?
they operate smaller regional and local ISP networks
What addressing schemes do the routers on the many interconnected networks use to shepherd packets to their destination?
IPv4 and IPv6
(routes them around network or power failures too)
____ enables packets to find their way from our IP address to one around the world
TCP/IP
____ provides a framework and common language for the Internet allowing programmers to build applications atop its features
TCP/IP
How are the high-speed backbone lines connected?
to backbone routers
What enables communication and services for building applications that enables humans/machines to interface across vast distances?
TCP/IP
What are DNS servers?
Special computers that keep databases of IP addresses and their corresponding names
(Walmart.com’s IP address = Walmart.com)
What does DNS stand for?
Domain Name Service
How do you setup a DNS name for your website? How does it work?
3 steps
- You set up the website
- Pay for a DNS server to register the DNS name to your IP address
- When someone types in the DNS name (www.totalsem.com), their system will query the DNS server to get the IP address for that name.
How do you get a domain name that others can access on the Internet?
Register the domain name and pay a small yearly fee
What are top-level domains? (TLDs)
the ending part of a domain name
(.com)
What are the original 7 top-level domains?
1 .com
2 .edu
3 .mil
4. .int
5 .org
6 .gov
7. .net
Why was a new level of domains added to the original 7?
to indicate a DNS name from a particular country
(.uk, .ca)
What does ICANN stand for? What is it?
Internet Corporation for Assigned Names and Numbers (ICANN)
they’re the organization that manages domain name assignments and created more top-level domains (.name, .biz, .info, .tv)
What’s the difference between starting a website now and then?
Before you’d need to set up the infrastructure to host it (build a system, install web server, get commercial-grade Internet link, obtain and properly configure the box with a public IP address, set up firewalls, and provide real-time administration to that system)
Now, you just host some space on a single server provided by hosting services (but not flexible)
Early websites were more like ____ and modern ones are more ___
Early websites were more like documents and modern ones are more dynamic like applications
What do you call modern websites? (2)
- Web application
- Web app
What is front-end code?
the code that runs a web browser to create the interface
What is back-end code?
Runs on one or hundreds of servers and does the heavy lifting
What is front-end and back-end code a complex collaboration with?
web applications/web apps
What happens when web apps are busy?
they launch a copy of the application on a new server to handle the additional traffic
What do you call an application that’s running on many servers?
Distributed
(because the work it does is distributed among many systems)
What happens when traffic dies down to certain web apps that had to launch a copy of the application on a new server?
they destroy the excess servers (virtual servers)
