WITH COMPLETE SOLUTIONS
DDoS Attack Correct Answer: A distributed denial-of-service attack tries to reduce or eliminate
a resource's ability to serve its users. The attacker overwhelms the resource by sending a flood of
messages from many compromised computers.
IoT (Internet of Things) Correct Answer: IoT devices are usually small devices such as
surveillance cameras that communicate directly with one another without human involvement.
There will soon be more IoT device using the Internet than humans surfing the Web, sending e-
mail, sending Excel and Word files, and doing other "humanish" things.
ISPs (Internet Service Providers) Correct Answer: Internet transmission or the delivery of traffic
from source to destination computers.
Hosts Correct Answer: Devices that are connected to the internet are called hosts.
IANA (Internet Assigned Numbers Authority) Correct Answer: controls and documents who
owns what IP addresses, since every single connected device outside of private networks needs a
unique address. The IANA prevents address duplication and ensures that devices can access the
World Wide Web.
IETF (Internet Engineering Task Force) Correct Answer: An organization that sets standards for
how systems communicate over the Internet (for example, how protocols operate and interact).
Cloud Correct Answer: An image that indicates that the user does not need to know what goes
on within the Internet. A general name for services provided by companies over the Internet.
Application Messages Correct Answer: A message sent from one networked application to
another over a network.
Server Hosts Correct Answer: The one that provides service is the server host.
Provides services to client hosts.
Server hosts include servers on server racks
Client Hosts Correct Answer: The one that receives service is the client host.
Receives services from the server host.
Client hosts include your mobile phone, tablet, PC, smartwatch, or anything else you use to
access services on the internet.
Rack Servers Correct Answer: A server that fits in a standard equipment rack. Most servers are
stored in equipment racks that are 48 cm (19 inches) wide and a standard height unit, or U, is
1.75 inches tall. Each rack can hold several rack servers positioned one on top of another.
, U Formula:
U rack x U height = inches available space
22 U rack x 1.75 = 38.5 inches of usable space
Networked Applications Correct Answer: Those applications that require a network to
communicate with one another in order to function.
Your browser, which is your client program, sends a request message to the webserver. This is
an HTTP request message because HTTP (Hypertext Transfer Protocol) is the standard for
browser-webserver interactions. This request message asks for a file to be delivered. The
webserver server program on the webserver locates the file and sends it back in an HTTP
response message containing the requested file (or an error message to say why it could not be
delivered).
Client Program Correct Answer: Program that receives service from a server program on a
server host.
Request Message Correct Answer: In request-response cycles, a message a client programs
sends to request service from a server application program.
HTTP Request Message Correct Answer: In HTTP, a message in which a client requests a file
or another service from a server.
HTTP (Hypertext Transfer Protocol) Correct Answer: The protocol that governs interactions
between the browser and the webserver application program.
The standard for browser-webserver interactions.
Server Program Correct Answer: Program on a server host that provides service to a client
program on a client host.
HTTP Response Message Correct Answer: In HTTP, a message in which a server responds to a
client request; contains either a requested file or an error message explaining why the requested
file could not be supplied.
Source Host Correct Answer: Host that transmit a message to another host, the destination host.
Destination Host Correct Answer: Host that receives a message from another host, the source
host.
Transmission Correct Answer: A source host sends an application message to a destination host.
Network Stack Correct Answer: Programs on a host that govern communication to and from the
Internet.
Two Processes: