13c Protocols Flashcards
What is the tcp/ip stack?
It defines the rules for transmitting data packets across a network. It is made of four layers that group a variety of protocols to transmit data.
What are the four layers of tcp/ip (ordered)?
Application
Transport
Network
Link
What is the function of the application layer of tcp/ip?
Selects the appropriate protocol for communication.
Interacts with the user via application software e.g. web browser.
What is the function of the transport layer of tcp/ip?
Establishes end to end communication.
Message split into packets and numbered.
Destination port is chosen.
Deals with error control (acknowledgement)
What is the function of the network layer of tcp/ip?
Supplies destination and source IP address.
Involved with packet routing.
Figures out the best route.
What is the function of the link layer in tcp/ip?
Adds MAC addresses.
Moves packets between two internet hosts.
Adds frame and header packets.
Deals with the physical connection.
Includes network cards/drivers.
What does https do?
Hyper Text Transfer Protocol Secure allows web pages to be exchanged between a client and a server over the internet.
What does FTP do?
File Transfer Protocol is responsible for allowing clients to upload and download files from servers.
What does POP3 do?
Post Office Protocol allows emails to be downloaded onto a single device
What does IMAP do?
Internet Message Access Protocol allows users to access emails by storing them on a server meaning multiple devices can access the same email.
What does SMTP do?
Simple Mail Transfer Protocol is responsible for the sending of emails by relaying them through email servers.
What does SSH do?
Secure Shell allows you to securely log into computers remotely.
What does TCP do?
Transmission Control Protocol is responsible for establishing an end to end connection and keeping track of packets.
What does UDP do?
User Datagram Protocol allows packets to be quickly sent over the internet.
Less reliable than TCP
Good for streaming as you don’t have to wait for all data packets to arrive before using data.
What is IP?
Internet Protocol
What is MAC
Media access control
What 6 protocols are included in the application layer?
HTTP
FTP
POP3
IMAP
SMTP
SSH
What protocols are included in the transport layer?
TCP
UDP
What protocol is included in the network layer?
IP
What protocol is included in the link layer?
MAC
What is the client-server model?
Clients send requests for data to the server.
The server sends back the data.
The server is referred to as back end and the client front end.
What are the crud statements for http?
Post
Get
Put
Delete
What are the crud statements for SQL?
Insert
Select
Update
Delete
What does rest / representational state transfer?
It’s an API that allows JavaScript to talk to a database server through HTTP. It translates the HTTP request into a language that can interact with the server.
What do JSON and XML do?
Both are self describing languages that work with hierarchal values. They are used by lots of different languages to retrieve data from web servers for web applications.
What are the differences between JSON and XML?
JSON is easier to read, more compact and can use arrays. It also doesn’t use end tags.
XML is more flexible and has more features.
How are XML and JSON parsed?
XML - parsed with XML parser
JSON - parsed by the standard JavaScript function
What is data parsing?
Changing data from one language to another.
What is a thin client?
Software/device that relies entirely upon a server (cloud) for processing.
