Web services are now preferred over Remote Procedure Calls.
What is main difference between them?
Currently most Web services architectures adopt RPC as their
architectural style. But because of the complexity of RPC, there are
bottlenecks of RPC-style Web services in Web-scale applications. REST
not only can make full use of Web features, but also has the advantage
of simplicity. So REST becomes a new alternative to RPC for Web
services architecture. In this paper, at first the brief introductions
of RPC and REST are provided. Then two kinds of architectural styles
are analyzed and compared from the perspectives of scalability,
coupling, and security. In the end the development trend of Web
services architecture is prospected.
Copied from: http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5339611
Web Service a higher level representation of RPC. A web service is a
specific implementation of RPC. At its lowest level, all a web service
is, is connecting to a socket, using the HTTP protocol to negotiate
sending a payload that is executed in a remote space (it may even be
on the same computer, for all the consumer knows). All those
abstractions are at its core RPC.
Copied from: What is the difference between remote procedure call and web service
Further attributes of a Web Service in addition to what Wayne wrote:
allows a platform independent way of a RPC, is discoverable and self
describing (compare that with a Win32 RPC)
http://savas.me/2005/07/web-services-are-rpc/
Related
Right now I'm working in WebApi (trainee developer), and have good knowledge in webapi . But , I don't know anything about WebServices.
My Questions are :
1.What is WebServices?
2.What is the Use of WebServices?
3.Instead of WebServices why we are using WebApi.
4.Where we can use WebServices?
5.At a time We Can use both Webservices and WebApis?
Exposing the Existing Function on the network
A web service is a unit of managed code that can be remotely invoked using HTTP. That is, it can be activated using HTTP requests. Web services allow you to expose the functionality of your existing code over the network. Once it is exposed on the network, other applications can use the functionality of your program.
Interoperability
Web services allow various applications to talk to each other and share data and services among themselves. Other applications can also use the web services. For example, a VB or .NET application can talk to Java web services and vice versa. Web services are used to make the application platform and technology independent.
Standardized Protocol
Web services use standardized industry standard protocol for the communication. All the four layers (Service Transport, XML Messaging, Service Description, and Service Discovery layers) use well-defined protocols in the web services protocol stack. This standardization of protocol stack gives the business many advantages such as a wide range of choices, reduction in the cost due to competition, and increase in the quality.
Low Cost Communication
Web services use SOAP over HTTP protocol, so you can use your existing low-cost internet for implementing web services. This solution is much less costly compared to proprietary solutions like EDI/B2B. Besides SOAP over HTTP, web services can also be implemented on other reliable transport mechanisms like FTP
For Example in Asp.Net Core : https://dzone.com/articles/step-by-step-aspnet-core-restful-web-service-devel
So I have currently been assigned to read about Web Services. I was going through the differences between REST, XML-RPC and SOAP and came across this particular link :
REST vs XML-RPC vs SOAP
It mentions this following, in terms of authentication and authorization
As for authentication and authorization, SOAP places the burden in the hands of the application developer. The REST methodology instead takes into account the fact that Web servers already have support for these tasks. Through the use of industry-standard certificates and a common identity management system, such as an LDAP server, developers can make the network layer do all the heavy lifting.
I was not able to understand this particular reference. Can some one explain how this happens in detail?
A web service is method or mechanism to communicate between different applications using open standard such as XML, WSDL, and SOAP. Using web service different device or program communicates over network
Type of WebService
SOAP Web Service
RESTFul Web Service
more information you can check :http://entityclass.in/rest/home.htm
I am trying to learn rest web service and every where i found written that rest works on HTTP protocol. I just want to know what other protocol can be used for building rest service. Link for an example will be great help
REST is 'bound' to HTTP, since the use of the HTTP methods GET, POST, PUT, DELETE is quite central to REST.
First of all, REST is is a software architecture style for building scalable web services.
You are talking about REST when applied to webservices.
Web service APIs that adhere to the REST architectural constraints are
called RESTful APIs.
To answer your question
what other protocol can be used for building rest service
I first need to clarify some things:
You are asking about underlying web service protocols.
Now a web service is "a software system designed to support interoperable machine-to-machine interaction over a network". The network you are interested in is also the best know i.e TCP/IP aka the internet.
Now you are interested in particular about web services which adhere to the REST architectural constraints.
A REST-compliant Web service would be one who's primary purpose of the service is to manipulate representations of Web resources using a uniform set of stateless operations.
The protocol that is used for a RESTful web service
First you need to understand that you are addressing the application layer of the OSI model. HTTP is an application layer protocol of the OSI model.
Theoretically protocols from this list(application layer protocols) which :
can be used to build web services
conform to the REST architectural constraints (stateless,layered system)
could be used for a REST-ful service.
What does a Web service really mean ? I am not looking for a theoretical explanation, I am looking for something practical.
I was thinking that anything I can call from an external client is a Web service, so a basic PHP which returns JSON data could be a Web service.
But then I started reading about Web services in W3Schools.org and I got confused. If the PHP URL which returns JSON data is a web service, why would I need to do SOAP, WDSL etc ... to create a Web service. Isn't it extra work?
Also, if SOAP is the way data is sent back and forth, what about other transport types?
What differentiates a RESTful Web service from a SOAP based web service?
When you are talking about a webservice people generally misunderstand what it means, a webservice is simply a way to interact between a and b that abstracts the use of local technology standards. A WSDL defines the way in which the SOAP message is being sent over the channel. REST uses JSON over HTTP, WSDL uses SOAP over HTTP.
The advantage of a webservice is, say you develop one piece of code in .net and you wish to use JAVA to consume this code. You can interact directly with the abstracted layer and are unaware of what technology was used to develop the code.
SOA is a set of design paradigms and standards that tell you how to develop your services, in SOA each service is meant to comply with the principles listed below. WSDL is generally linked with but not essential for a SOA solution. If you wish to learn about SOA google "Thomas Erl SOA".
Priciples of SOA
Standardized service contract
Service loose coupling
Service abstraction
Service reusability
Service autonomy
Service statelessness
Service discoverability
Service composability
This Q&A Restful vs Other Web Services brings a lot of light to what is a webserver, and differences from SOAP and REST. Id recommend to read all the answers (many of them are very good).
I am developing an appplication that consume data from WCF Web Service, but the data need to be retrieve from differents servers applications provided by different suppliers.
The question is what programming language support the develop of a Web Services from a WSDL that already exist?
For example in .NET you could use "wsdl.exe /serverInterface" to generate a server interface. See Implementing Service Interface
In Java see: Top Down Java Bean Web Service
But I don't want the suppliers to be attached to an explicit tecnology.
... I don't want the suppliers to be attached to an explicit tecnology.
You are taking about web services. The idea with web services is that it allows interactions between heterogeneous machines (and technologies).
For the interaction to happen, there is no need for the machine to use the same programming language or technology. What's important is the protocol used. In your case SOAP.
The protocol defines the communication interface or contract. For web services, the interface is described by the Web Services Description Language (your WSDL).
WSDL is in a (more or less) human readable format, but more importantly in a machine-processable format. The idea is that you use the WSDL to generate the code/classes that respect the contract; at the server side they are called Skeletons, and at the client side, Stubs.
A lot of programming languages have means or tools to generate stubs/skeletons from WSDL but again, that's not the important part. The important part is respecting the contract.
The WSDL just allows you to automate the creation of some boilerplate code. It's not mandatory to use the WSDL to create the server/client so any technology can be used (with or without the WSDL).
As long as you do that, you do not attach yourself to an explicit technology. So in the "WCF Web Service" you mention, you can drop the "WCF" word.
The only care you must take is with the interface between the systems. You must ensure the Web Services Interoperability as we don't live in an ideal world and some specifics from the technology stack "could leak" in the contract if you are not careful.