Friday 17 April 2015

Web Services interview questions and answers for fresher

Web Services interview questions and answers for fresher

Question: What is web services?
It is method of communication between two devices Over the network. With use of web service we can send the request to another device and get the response.
For Example:
We want to know the current weather of "New York, USA".
For this we contact a web service which store the weather information.v Now, We just call York, USA [It is dummy, just for example]
(Here i have pass city name with country (It is request), they will return the city weather information(It is response))

Question: What are famous web service protocols?
In development world, we listen someone using SOAP another one using JSON and third one is using XML-RPC.
Many times, it confuse us that What is these and whey they are using different.
These all are webservice because they are using for exchanging the information.
These are web service but they using different protocol as per their requirement.

Following are some famous protocol used by developers.

  • XML-RPC - XML Remote Procedure Call
  • REST - Representational State Transfer
  • SOAP - outgrowth of XML-RPC, originally an acronym for Simple Object Access Protocol
  • UDDI -Universal Description, Discovery, and Integration
  • WPS - Web Processing Service
  • XINS Standard Calling Convention - HTTP parameters in (GET/POST/HEAD), POX out.

Question: What is XML-RPC?
XML-RPC is one of the protocols that use XML for messages between two server.v It is used to "Remote Procedure Calls" using XML.

Question: What is JSON-RPC?
JSON-RPC is one of the protocols that use JSON for messages between two server.
It is used to "Remote Procedure Calls" using JSON.
Format of JSON
{ "version": "1.1", "result": "done", "error": null, "id": "194521489" }

Question: What is JSON-WSP?
It is another term of Web Services only difference is that It uses JSON instead of XML for exchanging the information between two server.
JSON-WSP is simpler as compare to Web Service.

Question: What is SOAP?
SOAP is the protocol used in order to do transfers the data among computers.

Question: What is WSDL?
WDSL is that which describes the interface used in a specific service.

Question: What is Web API? A Web API is a Web services where emphasis has been moving to simpler representational state transfer (REST).
RESTful APIs do not require XML-based Web service protocols (SOAP and WSDL) to support their interfaces.
RESTful mostly use JSON, because it is fast and human readable.

Question: What is REST?
Representational State Transfer (REST) is a software architecture(protocol) style consisting of guidelines and practices for creating scalable web services.
It is simpler as compare to SOAP, WSDL based web services.
It is mostly used by Web pages using HTTP Request.

Question: What are differnet channels used for communication using web services?

Question: What kind of security is needed for web services?
Web services should give response only to autorization calling server.
With each request, sender must send the authorization code and that must be validate by service provider.
We can use SSL for add extra security.

Question: Define Entrust Privacy Service?
It deals with security and confidentiality. This service encrypts data to ensure that only concerned parties can access the data.

Question: What is PKI?
It means Public-Key Infrastructure.

Question: What tools are used to test a SOAP and RESTFul services?
"SoapUI" for SOAP Web service and "Firefox poster plugin" for RESTFul services.

Question: What are distributed technologies?
The increasing ratio of distributed applications has raised demand for distributed technologies.

Question: What is the Web service protocol stack?
The Web service protocol stack is an evolving set of protocols used to define, discover, and implement Web services.