replacing MarshalByRefObject with safer option in C#

Question

I've tried to find a solution at stackoverflow but can't seem to find one quite like mine so here it goes. I have a computer in the lab that is connected to various devices like pan/tilt units, cameras, and light sensors and has all their drivers installed. I have C# code on the lab computer that knows how to talk to the hardware. The C# code can set an exposure time, ask for a picture, get one back, and display it in a picture box. I can tell the pan/tilt to move to a location and have it respond when done. If I am in the lab, it all works just the way I want.

The problem is that I want it to feel like I am at the lab computer when I am really at another computer. Most likely, I will be running the code that is on the non lab computer from inside Visual Studio. The program running in the lab will not be running from Visual Studio. With Remoting, this is a piece of cake. Put the code that talks to the hardware into a class, use MarshalByRefObject along with an interface I create, add RegisterWellKnownServiceType and presto I can use GetObject to get a reference and control it like I was sitting at the computer in the lab. So I know that remoting will work.

However, remoting is being phased out for WCF not to mention its not real safe out in the real world. It appears to me that WCF is going to make a local copy (by value) of the remote object which means it will not be on the lab computer and therefore unable to interact with the hardware that is attached. Someday this lab computer and all the sensor equipment is going to be moved away and I will have to access it remotely using the internet. A couple of years ago I did this exact thing but I was using remoting. Since remoting is so insecure, how do I do this without using remoting? Does WCF not have something equivalent to MarshalByRefObject? If WCF only uses by value, then it seems like they are phasing something out without providing functionality to replace it. Is there a way to use remoting that is not insecure? Is there something else besides WCF I should use?

This may be long winded but I see lots of people get dinged for asking questions that aren't very clear so I am trying to be clear. If there is already a post that truly provides me the best answer to my question, I must first apologize for not finding it myself but ask that a link be provided so I can get the answer there.

Answer 1

It appears to me that WCF is going to make a local copy (by value) of the remote object which means it will not be on the lab computer and therefore unable to interact with the hardware that is attached

This is almost entirely incorrect. There is no "copying" being done across machines. In fact the whole terminology around the "remote object" no longer has much meaning with WCF.

There is no remote object, simply a service. The service exposes operations across it's boundary. Service consumers can call those operations. When a consumer calls an operation, that call passes into the service and can cause the state of the service to change (for example, to talk to some hardware devices).

The service can also send a response to the caller, which can then cause the caller state to change (for example, to display output from the hardware device).

In order to make this happen you first need to create a service definition. Then you need to host your service on the lab machine. Then you need to create a service client, which you can then use on your local machine to call the service operations.

(How to) handle the situation where the port connected to the hardware on the lab computer fires a DataReceived event that needs to be picked up by my application

This is a more complex requirement but yes, WCF supports duplex communications with it's clients.

When you are defining your service contract you can specify that consuming clients implement a callback contract. This forces clients to define a callback operation which is exposed over the communication channel between service and client, and which the service can then call to "push" information to the client.

You should have your service use the WSDualHttpBinding WCF channel binding, which will use port 80 in both directions, allowing this to go across the internet.