ASP.NET - web service vs dll reference - Asked By anbu n on 15-Apr-11 10:28 PM

what is the main advantage or use of web service compared to normal dll ,
can' t dll be used every where instead of webservice..
Riley K replied to anbu n on 15-Apr-11 10:43 PM
Hi

     

Web Services offer many benefits over other types of distributed computing architectures.

  • Interoperability - This is the most important benefit of Web Services. Web Services typically work outside of private networks, offering developers a non-proprietary route to their solutions. Services developed are likely, therefore, to have a longer life-span, offering better return on investment of the developed service. Web Services also let developers use their preferred programming languages. In addition, thanks to the use of standards-based communications methods, Web Services are virtually platform-independent.


  • Usability - Web Services allow the business logic of many different systems to be exposed over the Web. This gives your applications the freedom to chose the Web Services that they need. Instead of re-inventing the wheel for each client, you need only include additional application-specific business logic on the client-side. This allows you to develop services and/or client-side code using the languages and tools that you want.


  • Reusability - Web Services provide not a component-based model of application development, but the closest thing possible to zero-coding deployment of such services. This makes it easy to reuse Web Service components as appropriate in other services. It also makes it easy to deploy legacy code as a Web Service.


  • Deployability - Web Services are deployed over standard Internet technologies. This makes it possible to deploy Web Services even over the fire wall to servers running on the Internet on the other side of the globe. Also thanks to the use of proven community standards, underlying security (such as SSL) is already built-in.

 


Disadvantages

With a web service, you will need to think about your network, firewalls, performance, etc. It also makes it harder to debug since you won't be able to step into the web service from your clients, you will have to set breakpoints on both sides of the calls.

The other problem with web services for you is that you need to be much more robust handling failures. With a DLL, you know a call to a method is going to succeed, but with a web service, you will need to be prepared for that call to fail or time out whenever you make any call across.

Although the simplicity of Web services is an advantage in some respects, it can also be a hindrance. Web services use plain text protocols that use a fairly verbose method to identify data. This means that Web service requests are larger than requests encoded with a binary protocol. The extra size is really only an issue over low-speed connections, or over extremely busy connections.

Ravi S replied to anbu n on 16-Apr-11 02:33 AM
HI

DLL

A dynamic-link library (DLL) or Assembly is an executable file that acts as a shared library of functions. It is an application programming interfaces (API) that is accessed by direct reference and application runs on your system.

Web Services

Web services are typically application programming interfaces (API) that are accessed via HTTP and executed on a remote system hosting the requested services.

Refer the links for moore information

http://msdn.microsoft.com/en-us/library/ms972326.aspx

http://forums.iis.net/t/1149966.aspx