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Create Pub/Sub service WITHOUT third parties tool

I would like to find a solution to create a pub/sub medium for 2 microservices to talk to each other,
I am aware i can use some third parties E.g Redis, RabbitMQ
Implementing event-based communication between microservices (integration events)
The challenge lies on the client is unable to allow install any third parties tool due to security reason.
The messageQueue server in Windows won't be allowed to use too.
I can only use the applications that is only existed in the server.
Therefore i am asking if there is anyway that i can create one simple app using windows service.
It is a one-to-many relationship. I have one service that will be dealing with data, once if there is any update, it will publish to those services that is subsribed to it.
It seems my problem could be similar with
.NET Scalable Pub/Sub service implementation
WCF Pub/Sub with subscriber caching(link is dead on the WCF pub-sub)
but i dont see any critical solutions.
I was thinking to use data notifications that MSSQL offers as last alternatives, but seems like it could cause a bottle neck when the applications get scale up.
The internet is so much flooded with articles using third parties tool.
Thanks

Check out Rebus library, that allows using different transport methods to send end receive messages in just a line of code (so in the future you can change it without effort).
You could use SQL Server or try to develop your own transport method

How much WCF efficient to get real time data?

Suppose I have a thousand of hardware device(about 20,000) which send the data in real time. I have to capture this data and send all data to database and also show information in application.For this I am thinking to develop a WCF service which poll all the devices and get the data from devices and store in database.
So my question is "Is WCF efficient to do this or I should follow another approach "

I am thinking to develop a WCF service which poll all the devices
A WCF service cannot "poll". A consumer can poll, which is to say it can call a service over and over again, however there is no polling pattern built into WCF client channel. So any polling behavior will need to be programmed.
So my question is "Is WCF efficient to do this or I should follow
another approach "
What I suspect is that you actually want your devices to call the service and pass data, so what you are actually asking is Can a WCF service handle a high volume of calls?, to which the answer is Yes.
However, in order to get the best scalability you should expose a per-call service, and do this over netTcpBinding (basically sockets), which uses optimised encoding and is therefore higher performance.
This would only be available to a consumer running the WCF client stack. If WCF is not available on your devices then the next best option is probably an HTTP endpoint over webHttpBinding, which provides the best interoperability.
Can you please suggest some other technology?
Well, if you are happy using http on your devices you should look at nancyfx for hosting your service - it's a really nice, lightweight http container for .net.

why is wcf duplex required?

WCF duplex performs a callback after a method has run on the server that then runs code on the client.
If i want to execute a method on the client from the server at the push of a button on the server then i don't think WCF duplex is appropriate.
Why would i not just create a client and a server at each end of my 2 applications?

I was one of the people that commented on your previous question so I probably owe you an answer here :o)
You have posted rather a lot of code and I have not looked at it in detail. However, in general terms, there is a reason for using wsDualHttpBinding and duplex contracts in general instead of more of a peer-to-peer approach where you have services on both sides, as follows:
The duplex approach is appropriate where you have a clearly defined server that is running permanently. This provides the hub of the interaction. The idea is that clients are in some way more transient than the server. The clients can start up and shut down or move location and the server does not need to be aware of them in advance. When the client starts up, it is pre-configured to know where the server is, so it can "register" itself with the server.
In contrast, the server does not need to be preconfigured to know where the clients are. It starts up and can run independently of any clients. It just accepts "registrations" from all clients that have valid credentials whenever they come online, and can continue to run after the client goes offline. Also, if the client moves, it just re-registers itself with the server at its new location.
So the server is in some sense a more "important" part of the system. No client can participate in the communication without the server, but the server can operate independently of any client.
To do this with WCF duplex service, you have to do some extra work yourself to implement the publish/subscribe behaviour. Fortunately, the MSFT Patterns and Practises team have provided some guidance on how to do it
http://msdn.microsoft.com/en-us/library/ms752254.aspx
This is fundamentally different from a genuine peer-to-peer approach where there is no well-defined hub (i.e. server) for the network and each node can come and go without affecting the overall functioning of the network.

WCF Duplex is used when you have a Publish/Subscribe setting (also known as the Observer Pattern). Let's say you have a service that subscribes for notifications of some sort (e.g. new email). Normally, you would need to check periodically for updates. Using WCF Duplex, the subscriber can be notified automatically by the publisher when there are updates.

WCF Service dependencies

I have three wcf services A,B and C respectively ,since i wanted it to be SOA(Service Oriented Architecture) the way my setup works is when i send a request from client to server.
All the services are self hosted windows services.
Client sends request to service A (client has no clue about the other services B and C);
Service A eventually sends that request to Service B and Service C.
Service B and C sends response back to Service A which would be sent back to the client by service A.
Issue i m facing :If i make any changes in the code of Service B and rebuild and restart the service ,i am having issue getting the response back but when i restart all the remaining services then it works fine.
In other words my client doesn't get the response back unless i restart all the services(A,B and C) even though i just changed the code in only one service and rebuilt it.I know the thing works if i restart all the three services but i want to know is this the problem in my way of designing or it is something i have to deal with self hosted windows services.And all the services(A,B,C) are independent as none depends on each other.
Did some one ever see such things happened in SOA.I would be glad if some one can guide me to appropriate solution ?

Replace WCF between services with any sort of queue (one service publishes something, other can read when they are ready). Can be anything. Can be a simple table where you read from if there is something new. Can be RabbitMQ, NServiceBus, etc, whatever works for you.
Define messages you put into the queue: commands and events. Both are simple classes with properties, no logic there. Commands represent what the system is asked to do (RegisterUser, PlaceOrder, ect), events represent what the system has done (UserRegistered, OrderApproved, PaymentReceived, etc). Be explicit about actions, Don't do something like "I have changed all the properties of a user on the client, now I call SaveUser(user)". Your service supposes to know how to change objects, clients should only command what to do.
Never break your contract. It is easy, easier than it sounds: you can add things to your message contracts, but cannot remove. In other word you just keep your contract backwards compatible.
Now you have a much better design: services communicate only through messages in queues, messages are backward compatible. This means that you can stop any of the services at any time without impacting others: they will continue sending messages into queues, and when the stopped service comes back again it will catch up processing all the stuff from the queue.
Then, if you want, you can use the same approach with client interactions: if instead of calling WCF clients would only put their commands in some sort of a queue then service upgrades or other downtime would not impact user experience.
Example: if I use WCF to place an order or to put an item into a shopping card then if there is a problem or a service is down for maintenance I will not be able to do it. I would click a button and have a nasty error. More importantly my order will not make into the system.
In contrast, if there is a queue in the middle, I only put my command into the queue. Now even if my service is down at the moment, or experience a high load (and therefore slow) then my user experience is still the same and does not degrade. It is just my command will be processed a bit later, but as a client I don't really care. And my order will not be lost in this scenario. The system became fault-tolerate and self-balanced.
There are all sorts of fantastic tricks you can do if you simply put a queue in the middle instead of experiencing problems with spatial and temporal coupling that comes with WCF :)
And what I described is just the beginning... :)

You may want to consider using a service bus such as NServiceBus to help you accomplish your functionality.
The first issue it will help you address is the decoupling of your services via publish/subscribe messaging pattern. Rather than invoking web services in one or the other service, publish events that notify the respective services when something has occurred. In your case this would look something like this:
Client invokes web service in Service A.
Service A publishes a message "Client Command Received" which Service B and C subscribe to.
Service B and C handle this event and then publish events of their own.
Service A subscribes to both events and replies to the client.
The first and immediate benefit of using something NServiceBus is reliability. On top of that you are able to easily version your message without affecting your client or your respective services. NServiceBus has full WCF integration so your client can continue to send messages to your service as before.
One of the things that makes your scenario interesting is that you can't guarantee when Service B and C send their responses back to you. Do you keep the connection to the client open until Service has received their responses? Do you need both responses before you can send a the client its response? What happens if either or one of the service crash? What if there is a time limit to how long you can wait before a response is received by Service A? All of these questions and more can be answered with a feature in NServiceBus called Sagas. Check it out.
If using NServiceBus is not possible then things become more difficult. WCF doesn't support publish/subscribe out of the box so you will have to bake your own. At a minimum I would recommend using this to decouple your services. How you manage state and temporal coupling in your services is another matter. Save yourself the trouble.
There are other frameworks out there but if you want a developer centric, cost effective way to create a .NET based solution then recommend using NServiceBus.

WCF or Custom Socket Architecture

I'm writing a client/server architecture where there are going to be possibly hundreds of clients over multiple virtual machines, mostly on the intranet but some in other locations.
Each client will be gathering data constantly and sending a message to a server every second or so. Each message will probably be about 128 characters or so in length.
My question is, for this architecture where I am writing both client/server in .NET is should I go with WCF or some socket code I've written previously. I need scalability (which the socket code has in mind), reliability and just the ability to handle that many messages.

I would not make final decision without peforming some proof of concept. Create very simple service, host it and use some stress test to get real performance results. Than validate results against your requirements. You have mentioned amount of messages but you didn't mentioned expected response time. There is currently discussed similar question on MSDN forum which complains about slow response time of WCF compared to sockets.
Other requirements are not directly mentioned in your post so I will make some assumption for best performance:
Use netTcpBinding - best performance, binary encoding, requires .NET server / clients. I guess you are going to use Net.Tcp because your other choice was direct socket programming.
Don't use security if you don't have to - reduces performance. Probably not possible for clients outside your intranet.
Reuse proxy on clients if possible. Openning TCP connection is expensive if you reuse the same proxy you will have single connection per proxy. This will affect instancing of you services - by default single service instance will handle all requests from single proxy.
Set service throttling so that your service host is ready for many clients
Also you should make some decisions about load balancing. Load balancing for WCF net.tcp connections requires sticky sessions (session affinity) so that after openning the channel client always calls the service on the same server (bacause instance of that service was created only on single server).

100 requests per second does not sound like much for a WCF service, especially with that little payload. But it should be quite quick to setup a simple setup with a WCF service with one echo method just returning the input and then hook up a client with a bunch of threads and a loop.
If you already have a working socket implementation you might keep it, but otherwise you can pick WCF and spend your precious development time elsewhere.

From my experience with WCF, i can tell you that it's performance on high load is very very nice. Especially you can chose between several bindings to achieve your requirements for the different scenarios (httpBinding for outside communication, netPeerTcpBinding in local network e.g.).