BJC Unit 4 Review (based on Review sheet)

What is the purpose of protocol?

Standards that ensure that all of the different kinds of devices using the internet can interact with each other smoothly.

Application Layer Protocols have the highest level of abstraction. What do they do?

Application Layer Protocols define the language the message a computer is sending.

Transport Layer Protocols manage what?

They manage the breakdown of a message into packets to be transmitted by lower-level protocols and the reconstruction of the message from the packets upon arrival.

What do Internet Layer Protocols manage?

They manage the pathways that the data packets travel across network. They treat the internet like one large network.

Network Interface Hardware or “Link Layer” does what?

This protocol manages the physical interface connection to the local network for any given device.

HTTP

1. Hyper Text Transfer Protocol

2. It interprets HTML code instructions for page formatting.

DNS

1. Domain Name System

2. It converts user-friendly web addresses into IP addresses

TCP

1. Transmission Control Protocol

2. It simulates a reliable, long-term connection between two computers by only displaying data once all packets have arrived.

IP

1. Internet Protocol

2. The addressing protocol that manages routing of data between computers.

SMTP

1. Simple Mail Transfer Protocol

2. An email protocol that sends mail.

SSL/TLS

1. Secure Sockets Layer / Transport Layer Security

2. Protocol that allows for data to be encrypted to make it private and secure.

Give two examples of Link Layer Protocols

1. WiFI radio antenna

2. Ethernet Cable

What is an “open protocol”?

Open protocols are available for anyone to see, use and code with.

What is a “closed protocol”?

Closed protocols are industry secrets.

Who is the IETF?

The Internet Engineering Task Force. They develop and approve protocols.

What country dominates the decisions about internet protocols?

USA

Which technology is especially vulnerable to software bugs that make it possible for cyber criminals to hack them?

Smart Phones

What do Certificate Authorities issue?

The issues public keys use for encryption/decryption.

How do open standards help security?

They allow the good guys - mathematicians - to study cryptography so the bad guys can’t exploit secret ideas.

What is the difference between a kilobit, a petabit, a gigabit and a megabit? Order them from biggest to smallest.

Peta 1,000,000,000,000,000

Giga 1,000,000,000

Mega 1,000,000

Kilo 1,000

What is the best way to measure latency?

ms (milliseconds)

What is the best way to measure bandwidth?

Bits per second (kilo, giga, mega)