Web Service Protocols

Question 1

GET Method

Answer 1

It is used to request data from a specific resource.

The data is sent directly into URL.

Never to be used on sensitive data!!

Question 2

POST Method

Answer 2

It is used to send data to a server to create/update a resource.

The data sent to the server with POST is stored in the request body of the HTTP request. They are, therefore not visible to users.

POST is a little safer than GET, because the parameters are not stored in browser history or in web server logs.

Question 3

Advantages of GET

Answer 3

• The URL parameters can be saved together with the website address.
• If necessary, a page can also be retrieved via the browsing history

Question 4

Disadvantages of GET

Answer 4

• Lack of data protection
• The URL parameters are visible to everyone and stored unencrypted in the browser history
• Limited capacity of data length.

Question 5

Advantages of POST

Answer 5

• It offers the necessary privacy
• The data is neither cached nor does it appear in the browsing history
• It’s very flexible: Users can transmit short texts, but also data of any size or type, such as photos or videos

Question 6

Disadvantages of POST

Answer 6

• Unwanted duplicate orders for example if you go back as the form data must be resubmitted since it’s not saved anywhere

Question 7

Web Services four main technologies

Answer 7

• XML(Extensible Markup Language) – Encode and organize the message
• SOAP(Simple Object Access Protocol) – Defines message standards and acts as message envelope
• WSDL(Web Service Description Language) – Describes a web service and its functions
• UDDI(Universal Description, Discovery and Integration Service) – Dynamically find other web services

Question 8

AJAX

Answer 8

(Asynchronous Javascript and XML) – Creates more interactive web applications

Question 9

JSON

Answer 9

(JavaScript Object Notation) – Alternative to XML use, faster and easier to handle

Question 10

SOAP

Answer 10

Protocol which allows:
o Exchanging structured and typed information between peers
o Accessing services, objects and servers in a platform-independent manner

Question 11

SOAP Structure

Answer 11

o SOAP Envelope: Required
o SOAP Header: Optional
o SOAP Body: Required

Question 12

SOAP

Pro vs Cons

Answer 12

• Advantages of SOAP:
o Interoperability
o Extensibility
o Independent of platforms and programming languages
• Disadvantages:
o Lack of security
o Lack of efficiency
o Slow, because it uses XML format which must be parsed to be read
o It defines only syntax, not semantics of operations
o It does not really hide underlying message passing principle

Question 13

REST

Answer 13

(Representational State Transfer)
It is a software archit4ecture style that relies on a stateless communication protocol, most commonly, HTTP.

It relies on four basic http operations: GET, POST, PUT, DELETE

Question 14

REST

Pros vs. Cons

Answer 14

•	REST Advantages:
o	It has a simple model
o	Caching is supported
o	Proven base stds: http, URI, MIME, XML
o	Scalability
•	REST Disadvantages:
o	Schema to represent all URIs is complex
o	Limited support for HTTP PUT & DELETE
o	No complex queries are supported