Networking & Cellular
E05 The Internet — Study Guide
This guide covers The Internet as part of Networking & Cellular. Start with the vocabulary, then try to answer each question before revealing the answer. Connect these facts to a real network or cellular connection and practice the subject in the arcade when you are ready.
Acronyms first
| Term | Meaning |
|---|---|
| GCI | Ground Control of Intercept |
| SAGE | Semi-Automatic Ground Environment |
| URL | Uniform Resource Locator |
Key facts
On what date did the USAF collect intel of high airborne radiation off the Soviet Union's eastern coast?
3 September 1949
What was the Soviet Union's first atomic test called?
Joe-1
Which Soviet bomber is shown as the long-range Arctic-route threat?
Tupolev 16 'Badger'
Soviet bombers only needed to fly low about what percent of the time to evade GCI radar?
10%
After the Soviet bomb, the USSR became known as the…
Red Menace
Which service was assigned to improve the nation's air defense system?
Air Force
At full deployment SAGE had hundreds of radars, ___ direction centers, and ___ combat centers.
24; 3
Who at RAND investigated survivable communications networks for the Air Force?
Paul Baran
Paul Baran's 'On Distributed Communications, Volume I' was published in…
1964
Baran: the enemy should have to pay the price of destroying…
n of n stations
Which network system stores and maintains a database in a single location?
Centralized
Which network system has components on different computers collaborating by passing messages?
Distributed
Baran designed the network with no central control because he assumed…
any link could fail at any time
Baran's research built upon one of the first WANs, created for…
the SAGE radar defense system
WAN advantage per the Internet deck?
Greater network consistency and much easier to secure
WAN disadvantage?
The larger the network, the greater the cost of setup, operation and maintenance
ARPANET was developed under the direction of…
ARPA (Advanced Research Projects Agency)
ARPANET began in what year?
1969
How many university computers formed the original ARPANET?
4
Which was NOT one of the four original ARPANET sites?
MIT
The fourth original ARPANET node (with UCLA, UCSB, Utah) was…
Stanford Research Institute
The Internet is described as the world's largest…
WAN
What was a major building block of the internet?
Packet switching
A well-known set of rules and standards that lets parties communicate is a…
Protocol
Who invented the World Wide Web?
Tim Berners-Lee
The World Wide Web took recognizable form in…
1990
Which Web era is 'read-write-execute' where applications talk to each other directly?
Web 3.0
Which Web era let users contribute content (YouTube, Facebook)?
Web 2.0
Which Web era was read-only with little interaction?
Web 1.0
An IP address is compared to…
a street address for your home
Devices on the same local IP network can talk directly; different IP networks must communicate via a router.
True
Which is TRUE of hostnames vs IP addresses?
Hostnames carry no routing info; IPs have routing info embedded
An IPv4 address is fixed length with how many parts?
4
DNS translates between…
domain names and IP addresses
Order what happens when a user enters a web address.
Browser calls DNS for the IP → DNS provides the IP address → TCP connects to that IP
How many parts does a URL have (per slides)?
5
Which URL part tells web servers which protocol to use?
Scheme
Which URL part is like 'specific rooms' in the house of your website?
Subdomain
Which URL part is the name of the website?
Second-level Domain (SLD)
Which URL part specifies the TYPE of entity registering (.mil, .com)?
Top-level Domain (TLD)
Which URL part shows which section of a webpage you're on?
Directory
Each packet has a label, a sequence number, a destination address, and a…
checksum
The number of packets needed is determined by…
the size of the message
Which switching method establishes a dedicated path at the start and sends all packets in order?
Circuit switching
Circuit switching disadvantages?
Inefficient resource use; messages very easy to intercept
Which switching method sends packets on the most convenient route chosen at transmission time?
Packet switching
Packet switching disadvantage?
Packets need sorting at the destination
A packet consists of control information and…
payload (user data)
In the letter analogy, the outside of the envelope (address, stamp) is the packet's…
control information
Which protocol segments data and makes sure it's in the right order with nothing missing?
TCP
Which protocol chooses which wires and 'intersections' deliver packets over the fastest route?
IP
Routers on the internet use ____ to fix some congestion problems.
load balancing
Which protocol is for time-sensitive transmissions like video playback — low-latency and loss-tolerating?
UDP
UDP speeds communication by not requiring a…
handshake
How many fields does the UDP header have, each 2 bytes?
4
Which is NOT a UDP header field?
Sequence number
Which protocol is connection-oriented, full duplex, and requires a handshake?
TCP
Which protocol supports broadcasting?
UDP
Which provides error control and flow control?
TCP
A TCP packet is called a ____; a UDP packet is called a ____.
Segment; User Datagram
TCP uses a byte stream; UDP uses a…
message stream
UDP's flexibility and speed also create an opening for exploitation.
True
Practice this module
Continue with a Networking & Cellular game. Choose this module in games that offer module selection.