Below are the notes I took at the PDC about what’s new in WCF 4.0.

• Default bindings can be created. If no bindings are specified for a service, these bindings are used.
• WCf supports configuration inheritance, so bindings could also be specified at various levels including the machine.config.
• Same applies to behaviors
• Default bindings/behaviors are the bindings/behaviors that have no name or name=”” in the configuration
• Configuration based activation allows services without *.svc files
• ETW (Event Tracing for Windows) is used by WCF
• AppFabric (FKA “Dublin”) stores that data in a Sql Server database for easy retrieval and querying.
• Routing is a completely new feature in WCF which allows service aggregation, protocol bridging and versioning.
• MessageFilters are used to determine destination(s).
• Routing table can be changed at runtime.
• Security can also be bridged.
• Alternate endpoints can be specified for fail-over-safety.
• Discovery is another new feature. It allows for location agility, dynamic / self-healing apps
• Discovery adheres to WS-Discovery standards
• Two mode for discovery: Ad-hoc and managed
• Ad-hoc discovery uses broadcasts
• Managed discovery is like UDDI with a Discovery Proxy.