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Obtaining the IP and MAC of client machines connecting to my ASP.NET MVC application on a server

I have just signed up because I need some clarification. I am an old man but a new graduate of a Systems Analysis college program and am on my first "real" job designing a system for a local company. Here is the deal. I am using ASP.NET MVC. Now, the company has assembly lines in a large manufacturing plant. Along the lines are stations where workers do a specific job on the line. The company has paper instructions that explain to the worker step by step how to do the job at their station. They want all this done electronically now....this is what I 'm doing.
So, when the leader of the assembly line starts their shift, they log into the system by opening up IE and connecting to the application server. From there, the leader picks a part to "make" on the line. The system then goes into the repository of instruction documents and retrieves all the documents needed by each station on the line to run the selected part. The system then needs to prepare the documents according to the station that will use them (ie. station 1 docs, station 2 docs,....etc). Then, the system needs to automatically open up the IE browser window on the client machine at each station on the line and display the login screen. The worker then logs onto the station and is presented with the "dashboard" screen with the instruction forms right there in front of him with buttons to navigate through the various docs for his station.
So now, we are wanting to have the system store the IP and Mac addresses of each station machine along each assembly line in a table along with fields that denote the assembly line and station # (ie. so a row in the table would have MAC | IP | ASSEMBLYLINE-ID | STATION-ID). This table will be populated before hand by admins so that the system knows already what the Mac and IP are for each machine on the floor. So, when the leader picks a part to run, the system can just check the machine the leader is logged into and get its MAC and IP and then look up in the table what line the machine is on. Then it can create a document queue for each station on the line, and then when the queues are ready, it can look in the table for the IP's of each machine on the line so that it can open the log on screen on the right machines.
However, it is possible that IP's may change from time to time. For this reason, we want to make sure we also use MAC addresses to validate the identity of a station machine whenever any communication needs to happen between the system and the clients. IP's alone just aren't good enough. Further, we are using all zero clients for this on the stations.
So, if you're still reading, lol. How can my system on the server, run a getMAC command on a machine that connects to it?

A web server cannot get the MAC address of a client machine. MAC addresses are stored on the physical ethernet layer and are not routed through socket connections. A MAC address stored in a packet is changed on every hop of a packet's journey. MAC is an abbreviation for Media Access Control, with "Media" referring to the local communication media. While source and destination IP-Addresses remain the same throughout the journey (and are used for long-distance routing decisions), the source and destination MAC-Addresses just indicate the next hop.
That being said, you can get the IP address like so:
Request.UserHostAddress()
However, as you yourself pointed out, this isn't reliable. Especially if the computers are behind a proxy or firewall.
To address your real problem, which is identifying a machine in your assembly line, one method is to get the computer name. You can open a command window and type the command hostname and that will return the computer name. It should be unique for each of your machines. If not, you can set it by right clicking on Computer. To get this name through javascript, use this code:
function GetComputerName()
{
try
{
var network = new ActiveXObject('WScript.Network');
var computerName = network.computerName;
return computerName;
}
catch (e) { }
return "";
}
Note that this code will only with with Internet Explorer and it may require you to enable special security settings inside the browser.

setting/properties type setup

I would like to have the possibility of specifying certain "properties" either during setup of my app or afterwards.
In my app I have a connection to my mysql server,currently localhost, but when I am going to install this the localhost will probably change to an IP address or hostname, is there any way that I can create like a properties box that asks the user what he/she wants the ip address or hostname to be to connect to,and then once they change it it should reflect in the code? Or maybe have an encrypted text file with all the settings in or a text file thats hidden with the settings in,not sure what the right approach will be, thank you for your answers and advise

You can store sensitive data in connection strings by encrypting them, see MSDN Documentation.

Connect multiple server by webservices from asp.net

Thanks for reading my question.I wondered if you have any idea about this problem.
I wrote a SOAP-SERVER. Running it at CentOS. Changing Soap-Server's IPAddress for match with CentOS Ifconfig.
Running SOAP-SERVER in CentOS.
Using VisualStudio tools for AddWebReference .It'll auto generate a define object class.In this class,It containt all of function of SOAP-SERVER.
Developer will use these function for do something at ASP.Net-Client.
But,When I want to connect from ASP-NET to more SOAP-SERVER(in other CentOSs).And we musn't using AddWebReference .Because User will use web form for input IPAddress of these SOAP-SERVER.
Do you have any idea? Thanks for helping by anyway.Thanks

You'll have to keep a fixed no. of servers with same IP addresses, otherwise each time you want to access a service you'll have to change the Service proxy classes or service reference in visual studio for that matter.
What you can do is instead of letting the user enter the IP address, display a list all that you have and make him select one.

Get original url without non-standard port (C#)

First question!
Environment
MVC, C#, AppHarbor.
Problem
I am calling an openid provider, and generating an absolute callback url based on the domain.
On my local machine, this works fine if I hit http://localhost:12345/login
Request.Url; //gives me `http://localhost:12345/callback`
However, on AppHarbor where I'm deploying, because they are using non-standard ports, even if I'm hitting it at "http://sub.example.com/login"
Request.Url; //gives me http://sub.example.com:15232/callback
And this screws up my callback, because the port number wasn't in the original source url!
I've tried
Request.Url
Request.Url.OriginalString
Request.RawUrl
All gives me "http://sub.example.com:15232/callback".
Also to clear up that this isn't a Realm issue, the error message I am getting from DotNetOpenAuth is
'http://sub.example.com:14107/accounts/openidcallback' not under realm 'http://*.example.com/'.
I don't think I've stuffed that up?
Now, I'm about to consider some hacky stuff like
preprocessor commands (#IF DEBUG THEN PUT PORT)
string replace (Request.URL.Contains("localhost"))
All of these are not 100% solutions, but I'm sick of mulling over what could be a simple property that I am missing. I have also read this but that doesn't seem to have an accepted answer (and is more about the path rather than the authority). So I'm putting it towards you guys.
Summary
So if I had http://localhost:12345/login, I need to get http://localhost:12345/callback from the Request context.
And if I had "http://sub.example.com/login", I should get "http://sub.example.com/callback", regardless of what port it is on.
Thanks! (Sleep time, will answer any questions in the morning)

This is a common problem in load balanced setups like AppHarbor's - we've provided an example workaround.
Update: A more desirable solution for many ASP.NET applications may be to set the aspnet:UseHostHeaderForRequestUrl appSetting to true. We (AppHarbor) have seen several customers experience issues using it with their WCF apps, which is why we haven't enabled it by default and stil recommend the above solution for those situations. You can configure it using AppHarbor's "Configuration Variables" to inject the appsettings when deployed. More information can be found in this article.

I recently ran into an issue where I compared a URL to the current URL, and then highlighted navigation based on that. It worked locally, but not in production.
I had http://example.com/path/to/file.aspx as my file, but when viewing that file and running Request.Url.ToString() it produced https://example.com:81/path/to/file.aspx in a load balanced production environment.
Now I am using Request.Url.AbsolutePath to just give me /path/to/file.aspx, thus ignoring the schema, hostname, and port numbers.
When I need to compare it to the URL on each navigation item I used:
New Uri(theLink.Href).AbsolutePath

My initial thoughts are get the referrer variable and check if that includes a port, if so use it otherwise don't.
If that’s not an option because a proxy might remove the referrer header variable then you might need to use some client side script to get the location and pass it back to the server.
I'm guessing that AppHarbor use port forwarding to the IIS server so even though publicly the site is on port 80 IIS has it hosted on another port so it can't know what port the client connected on.

Something like
String port = Request.ServerVariables["SERVER_PORT"] == "80" ? "" : ":" + Request.ServerVariables["SERVER_PORT"];
String virtualRoot = Url.Content("~/");
destinationUrl = String.Format("http://{0}{1}{2}", Request.ServerVariables["SERVER_NAME"], port + virtualRoot, "/callback");

If you use the UrlBuilder class in the framework you can easly get around this. On the builder class if you set the port to -1 then the port number will be removed:
new UriBuilder("http://sub.example.com:15232/callback"){ Port = -1}
returns : http://sub.example.com/callback
To keep the port number on a local machine just check Request.IsLocal and don't apply -1 to the port.
I would wrap this into a extension method to keep it clean.

I see that this is an old thread. I had this issue running MVC5, on IIS 7.5, with an Apache proxy in front. Outside of the server, I would get "Empty Response", since the asp.net app gets the Url from apache with the custom port.
In order to have the app redirect to a subpath without including the "custom" port, forget the Response/Request objects, and use the Transfer method. For instance, if I want that users are automatically redirected to the login page in case they are not logged already:
if (!User.Identity.IsAuthenticated)
Server.TransferRequest("Account/Login");

Custom API requirement

We are currently working on an API for an existing system.
It basically wraps some web-requests as an easy-to-use library that 3rd party companies should be able to use with our product.
As part of the API, there is an event mechanism where the server can call back to the client via a constantly-running socket connection.
To minimize load on the server, we want to only have one connection per computer. Currently there is a socket open per process, and that could eventually cause load problems if you had multiple applications using the API.
So my question is: if we want to deploy our API as a single standalone assembly, what is the best way to fix our problem?
A couple options we thought of:
Write an out of process COM object (don't know if that works in .Net)
Include a second exe file that would be required for events, it would have to single-instance itself, and open a named pipe or something to communicate through multiple processes
Extract this exe file from an embedded resource and execute it
None of those really seem ideal.
Any better ideas?

Do you mean something like Net.TCP port sharing?

You could fix the client-side port while opening your socket, say 45534. Since one port can be opened by only one process, only one process at a time would be able to open socket connection to the server.

Well, there are many ways to solve this as expressed in all the answers and comments, but may be the simpler way you can use is just have global status store in a place accesible for all the users of the current machine (may be you might have various users logged-in on the machine) where you store WHO has the right to have this open. Something like a "lock" as is used to be called. That store can be a field in a local or intranet database, a simple file, or whatever. That way you don't need to build or distribute extra binaries.

When a client connects to your server you create a new thread to handle him (not a process). You can store his IP address in a static dictionary (shared between all threads).
Something like:
static Dictionary<string, TcpClient> clients = new Dictionary<string, TcpClient>();
//This method is executed in a thread
void ProcessRequest(TcpClient client)
{
string ip = null;
//TODO: get client IP address
lock (clients)
{
...
if (clients.ContainsKey(ip))
{
//TODO: Deny connection
return;
}
else
{
clients.Add(ip, client);
}
}
//TODO: Answer the client
}
//TODO: Delete client from list on disconnection

The best solution we've come up with is to create a windows service that opens up a named pipe to manage multiple client processes through one socket connection to the server.
Then our API will be able to detect if the service is running/installed and fall back to creating it's own connection for the client otherwise.
3rd parties can decide if they want to bundle the service with their product or not, but core applications from our system will have it installed.
I will mark this as the answer in a few days if no one has a better option. I was hoping there was a way to execute our assembly as a new process, but all roads to do this do not seem very reliable.