I want to control devices to remote location using Internet.
I did some Experiments. I have one Laptop connected via WIFI and a computer connected via Router. it works fine. now when i run from system connected to other router it did not worked even both had internet connections.
one reason may be it cannot trace IP because there are many computers. Did implementation done here http://csharp.net-informations.com/communications/csharp-server-socket.htm
is it possible to control devices over the internet?
secondly what is difference b/w Sockets and Winsock?
When you tried your system with wifi and the router I assume you were on the same network. Now you are using the internet you should be using the public IP addresses of your routers and map the port(s) you are using to the specific computers you want the data routed to. If you do not have static IP addresses available you probably should look into using something like DyDNS and OpenVPN to create a private network.
As far as your question about Winsock vs Sockets look at this article
Edit: Take a look at this article on port forwarding
Related
I would ask if it is possible to get information about connected devices in the local wireless network.
Is there any api for xamarin to do that?
It doesn't seem like Xamarin has an API for this, but Microsoft introduced a Ping (documentation here) and a NetworkInterface class (documentation here) in .NET 2.0 that you could use.
Essentially, what you need to do, is to ping the IP adresses on your local network, which you can do asynchronously using SendAsync(). You then register the callbacks by registering an EventHandler to PingCompleted. The callback will contain a PingCompletedEventArgs which you can use to retrieve basic information (e.g. IP, MAC and Hostname) about the device.
You can find a complete guide of the implementation here.
I hope this helps.
Note: Of course, it all depends on what type of information you expect to retrieve. Although, I think you can only expect to retrieve the basic information about devices on your network, as everything else could potentially be a security risk.
Secondary note: Depending on which devices you wish to discover on your network, you could also use the SNMP component which will allow you to discover devices such as routers, switches, printers, and so on.
I am thinking you are looking for which devices at layer-2 have registered with your wireless controller/accept-point/router and by being connected you are referring to how many have successfully establish 802.x handshake (implying security exchange and channel establishment has occurred).
There exists a tool to do this work (never tested this on my mac) and you can check Flying Squirrel for the above purpose. This will ofcourse be an independent sniffer over the wireless network and you'll require the password used for wifi etc. for making this work.
If you have access to a device that exposes instrumentation (MIB) then you can get that information from the device by SNMP walking the device. At this level you'll of course get the MAC address table and if DHCP is running on your router then perhaps access to DHCP table can give you information about the MAC to IP mapping. On some medium to high end networking gear MIBs like CISCO-DOT11-ASSOCIATION-MIB can be used. Also I am assuming you are refering to 802.11 here there are other wireless protocols like BlueTooth etc. in play as well which use different scanning techniques so the answer depends on what kind of network you are referring to here.
Ok, I figured out a way without snifing the local network. It makes more sense the following way in my case...
Case:
I want to connect to an device which provide an own wlan network. Then I connect to it and pass the home wlan network to it. The device restarts and is now configured as a client in the local home network. And now I need the local ip for service communications.
My Solution:
I do a register call to the device. The device gives me the mac address. Now I register (with phone device) the mac address from the access point device in a online service. After the device has been restarted and get the new local ip address it sends to the online service.
And the I can retrieve the local ip address through polling or through getting push notification from the server...
I'm working on a simple c# messenger and its works on the local network only. Does somebody know what should i do to make it works on the internet?
The solution contains the server project that listening on a certain port, and a client project connect to the server with that port.
Your clients need to be able to communicate with the server, which means that either:
You need to host the server application on a computer that is directly connected to the internet.
You need to setup port forwarding on the router that controls internet access for your network.
In either case the clients will need to know the IP address to connect to, and any firewall interactions need to be considered. This may also include ISP firewalls, as some ISPs limit inbound connections to subscriber connections.
I won't go into the specifics of setting up port forwarding on a router... there are plenty of examples, and every router is different. Google will help you with this if necessary.
Ideally you should have a static IP address for this, or some method for the clients to locate the IP address that your server is hosted on. If you must run from a dynamic IP address (such as some ISPs still use for subscribers) then one of the Dynamic DNS options might work for you.
In-order to make it work on Internet a simple answer is you need to enable ports which is used for communication.Generally the ports will be blocked by the Companies firewall for security reasons.So contact your IT dept to enable the port.
Or Use common port like 80.
I am creating an application that listens for connections (server) from a different application (client) via a tcp connection. So if both application where to be on the same network it will be easy to establish the connection. so I am trying to add a method to the server so that users do not have to open ports on their routers in order to make the app work when using it over the internet. so let me show you a few different scenarios:
1)---------------------------------------------------SCENARIO_1-------------------------------------------------------------
the server is a computer in a house. That computer is connected to a router and that router is connected to the internet. The client is a computer on a office that has access to the internet as well.
for this scenario to work, before I used to open the ports on the house router and forward them to the server computer. on the client I just had to supply the correct IP address and same port in order to establish the connection.
now I avoided opening the ports on the house router with a really cool technique:
first I add this reference:
then I tell the router which ports I want to be forwarded to my computer (the server):
NATUPNPLib.UPnPNATClass upnpnat;
NATUPNPLib.IStaticPortMappingCollection mappings;
public ServerExample()
{
InitializeComponent();
// server local IP address
mappings.Add(1300, "TCP", 1300, "192.168.0.120", true, "my server");
//.... etc
..
when doing this I am able to connect from my office computer by providing port 1300, the WAN ip address of the server computer which is a different one. (that address can be found at: whatismyipaddress.com) THE COOL THING IS THAT I DO NOT HAVE TO DO ANY CONFIGURATION ON THE ROUTER!!!
2)-----------------------------------------------SCENARIO_2----------------------------------------------
know here comes my problem. The server happens to be on a office. that server is connected to router A, router A is connected to router B and router B is connected to the internet. In other this example is like the last example on the server with an extra router in between. and the client is somewhere else. we do not care how the network setup is on the client computer as long as it has internet access.
the way I used to solve this was by forwarding the packages from router x to the server computer and also port forwarding the traffic from port x of router B to the ip address of router A. when setting up that configuration I was able to establish a connection with the client when providing the WAN ip address of the server. (the ip address that is shown at: whatismyipaddress.com when retrieved from the network of the office).
so it will be nice if I can avoid doing all this configuration on the routers and do something similar to:
public delegate void SomeDelegate(string parameters);
NATUPNPLib.UPnPNATClass upnpnat;
NATUPNPLib.IStaticPortMappingCollection mappings;
public ServerExample()
{
InitializeComponent();
// server local IP address
mappings.Add(1300, "TCP", 1300, "192.168.150.141", true, "my server");
mappings.Add(1300, "TCP", 1300, "another ip", true, "router's ip");
so I have been playing around with that and I have not been able to make it work. also it will be nice if I could find out if the server connection is like scenario 1 with c# or scenario 2 or maybe a different scenario so that the users setting up the server do not have to specify all that info. for example I am sure that limewire does something similar.
Edit:
here is scenario 1 illustrated:
and here is scenario 2 illustrated
The feature that you are using is called Universal Plug and Play (UPnP) which is basically a way for a device to tell another device how to communicate with it. What you are doing is telling a computer to tell the router what ports you want forwarded to it. Unfortunately UPnP is a non-routable protocol which means that it can't jump across routers. So the short answer is that doing what you are trying will not work with multiple routers without manually configuring the ones "farthest" away from the client.
It might be possible to do something with Internet Gateway Device protocol (IDG) but you'd have to research that more and the library you are targeting doesn't support that. Post this question to Server Fault and you might get a better answer. (Don't post your code, just explain the basics of your problem, that you're trying to have a machine register itself with a router using UPnP which is working but you have another router in front of that that you want to automatically forward, too.)
I am trying to connect 2 or more computers running a c# application. All TCP examples I find only show how to connect them if they are running on the same network.
My question is how to connect them over the internet?
I want to create a service like MSN but with direct connection (like a torrent software does),
any help?
regards!
Connecting 2 computers over the internet should, mostly, be the same as connecting them on a LAN. Your problems will mainly be with the firewall. In your C# code, you will have to assign an IP address & port for both computers. You should ensure that your firewall will allow this port through without blocking (beware of security vulnerabilities when opening new ports).
If your computers don't have public IPs, you will also have to set up some NAT on your router. This will map a port on your router + your public IP address to your local computers IP address + port. The other computer will then configure this public IP address + port in their configuration. There is too many configurable things that have the potential to screw up to list in a single post. I'd suggest learning some basics on networks.
However, having said all that, in terms of C# code you shouldn't have to change a thing to get the program to work over the internet if it works over a LAN.
I want to know how I can send or recieve data over internet to/from a computer in subnet
(this is specially in context to PPP users bcoz getting static IP is not so much in practice).
I actually want to create an application which can transfer file between 2 specific computer in WAN.
so what are things I need to know about to do the same..(ex. PRESENT IP or MAC ADDRESS etc..)
PROGRAMATICAL EXPLANATION ALTHOUGH PREFFERED,BUT IS NOT NECCESARY...
FTP?
There is a vast torrent of useful results in google, I seriously suggest to google before you ask here.
For instance, have a look at the top result: http://www.devarticles.com/c/a/C-Sharp/Network-Programming-in-C-sharp/
Apart from that, FTP, as suggested by Colin, may be what you're looking for. If you're new to using FTP in C# have a look at http://www.google.com/search?q=c%23+ftp
Put the information on a public IP server, so both computers keep polling if there is new data and send / download that data as needed. A single text file can hold necessary flags such as paths and other info you need.
server just need to be a web server, which means IIS or similar should be installed.
I'm thinking part of your question has to do with one of the computers not having a static IP address. If the two computers, A & B, don't know each others IP address, then an alternative is to use a server. Either A can store the information on the server to be picked up by B, or A can register his current IP address on the server for B to lookup and then connect to A, assuming firewalls don't interfere. Another scheme is that A and B can simultaneously connect to the server, and the server can relay data between the two.
Of course, all of this communication would be done using techniques such as those suggested by mafutrct and Colin.
This question sounds to me like the difficulties of NAT Traversal and trying to establish peer-to-peer connectivity over the Internet. I stumbled on this question researching the best way to set up Internet connectivity to a device that is sitting behind a firewall. I am assuming that the device behind the firewall has to initiate the connection, that a Internet server application (on a Public IP address) to at least manage the initiation of the connection is required, and the Internet server application may also have to act as a relay if the difficulties of NAT is not able to be traversed.
http://en.wikipedia.org/wiki/NAT_traversal
http://en.wikipedia.org/wiki/Peer-to-peer
A good example of this is LogMeIn. Where the application is installed on the computer that needs to be accessible over the Internet, that application communicates with the LogMeIn Internet servers, you can establish a connection to that computer either by initiating through the LogMeIn servers and connecting peer-to-peer over port 80/443 using NAT Traversal (this would be establishing a peer-to-peer connection) or by initiating through the LogMeIn server and the LogMeIn server acting as a relay if peer-to-peer is unable to be established.
Please note; you must have an application (something running) on both ends of the connection on the Internet, there is no other way. Just like FTP that was mentioned earlier (FTP Client, FTP Server)... but in this case it is peer-to-peer (basically you are writing your own Client and Server... or if you have to use a relay... Client--Relay--Server
http://en.wikipedia.org/wiki/LogMeIn
"The service connects the remote desktop and the local computer using SSL over TCP or UDP and utilizing NAT traversal techniques to achieve peer-to-peer connectivity when available."
The part I don't know is can the relay go in both directions; and I am figuring the device behind the firewall must have to constantly manage the open connection to the Internet Server that is the relay. Those are the questions I am wrestling with now.
Also, you may want to check out this post.
C# byte streams through TCP
From that time, till this date I have encounter so many problems with these four kinds of NAT that basically without an external server you cant do anything.
This is because, one computer can never find where the other one is located as suggested in the pic.
Here PC 'A' will never come to know about the port that corresponds to PC 'B' on R2B without an external server.Even more, if somehow u come to know about the ports you are still in a situation that the router wont allow you to access it if the request hasn't been made for your IP.