ASP.NET Web services are designed to directly interact with other applications (Objects) over the internet. Web services are platform-independent and language-independent, which was developed for building applications that communicate using standard web protocols and data formats such as HTTP, SOAP, and XML.
So, developers just need to understand how to send and receive SOAP messages and no proficiency is required in the platform, object model, or programming languages to execute the service. The web services lack versatility and a lot more, which gives birth to WCF.
WCF is a framework for building service-oriented applications that enables communication with other software entities using any transport protocol. When you are using WCF, the message could vary from simple single character to the complex stream of binary data. WCF is more reliable, secure and efficient in data transmission.
Both ASP.NET web services and WCF development services have some advantages. It's unfair to say, one is superior to another, but, in turn, confuse the developers to identify what to use and whatnot.
Here is the list that enlists and demystifies what's the difference between these two services:
1. Web services use XMLSerializer which does not specify which fields or properties of the type are serialized into XML, while WCF uses DataContratSerializer that shows which fields or properties are serialized into XML. That's why WCF is preferred over web services, as DataContratSerializer performs better than XMLSerializer.
2. Web services support only one protocol- HTTP and HTTPS during communication, but WCF supports more protocols like- HTTP, TCP, and MSMQ that can be extended for a comprehensive solution, reliable session, and transactions. It signifies WCF is more adaptable to work together for a variety of software.
3. WCF offers much flexibility as web services can only be hosted in IIS, while WCF can be hosted in IIS, windows activation services, self-hosting, and Windows services.
4. WCF is excellent for building real-time applications because it's more reliable, fast and robust as compared to the web services.
5. Web services perform far better than WCF services even when they both execute some actions.
6. ASP.NET web services don't support duplex operations but WCF does.
7. When WCF development services are used, the hash table can be serialized, but not when using web services. Web services serialize only those collections that incorporate IEnumerable and ICollection.
8. Using service behavior classes, WCF supports multi-threading, but web services don't.
9. In ASP.NET Development services, SOAP messages are exchanged over HTTP, but WCF services can exchange the message using any format over any transport protocol. Though, SOAP is a default format that WCF uses.
10. WCF services have timeouts by default that can be configured. In WCF services, if the communication channel cannot be opened/ closed and there is no response within the time span, then WCF services get timed-out. Web services don't have any such property.
Considering the above differences, it seems WCF is replacing web services (The older service oriented architecture developed in the .Net framework). But, WCF won't support the overloading method.
It would be biased to say which one to prefer. So, decide on your own what you want to use WCF development services or .NET development based on your project requirements and functionalities.