Is it possible to connect to a Air app running on another machine via socket(assuming we know ip) or some other mechanism(which doesnt use Cirrus/stratus)? If it is can someone please help me on how?
Let me rephrase question, I dont want to connect to a server over socket. I would like to know if it is possible to connect from one AIR app on machine A to connect to another AIR app on machine B via sockets without cirrus. I'm not asking for someone else to do my work, I couldnt find any documentation or possibility of the above thing. My conclusion now is that it is not possible, but I would just like it to be verified by other people(experts).
Absolutely, as3 supports sockets. http://www.ultrashock.com/forum/viewthread/81676/
http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/net/Socket.html?filter_flash=cs5&filter_flashplayer=10.2&filter_air=2.6
There are two ways to do it. One AIR app can act as a server by creating a ServerSocket object while the other app connects to this with the Socket class. The other way is to use the DatagramSocket class.
In both cases, the trick is that because of network access translation, the IP address to use is not always easily discoverable unless at least one of the computers has a static IP. If both computers are on the same network subnet you can look up the IP address needed to reach one computer from the other manually. Otherwise, the IP one computer must use to reach the other won't be the same IP that the computer sees for itself. This matchmaking is the service that stratus/cirrus provides.
See http://www.brynosaurus.com/pub/net/p2pnat/ for a description of the problem.
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I'm currently looking at options to allow me to build a remote COM-port solution.
The idea is to be able to access from my remote PC, another PC that's directly connected to a device locally via its serial COM-port.
I know that the obivous answer is to use a VPN between the 2 Internet connected PCs.
However, I need this solution to be as seamless to the end-user as possible.
i.e. no installing and configuring VPN software, etc.
So I was thinking that WebRTC would be great because the end-user can simply use their web-browser and not have to install any additional software.
My question is, is it possible to stream the COM port data between the 2 PCs via WebRTC?
If so, can you please point me in the right direction as to how I can go about achieving this?
Sorry if this is a ridiculous question, I'm very new to WebRTC, just exploring my options.
Thanks.
That should work great!
Networking wise you get NAT Traversal. That means the two computers can be in completely different networks, and still communicate. You may have to run a TURN server if P2P isn't possible.
Data wise you can exchange anything you want via data channels. It is datagram based and you can send/receive binary data. You get a callback telling you how much has been delivered, that way you can detect backpressure.
Are you ok with installing software on the remote host? You can do something like Pion WebRTC's data-channels. This shows you can have a browser connect to a Go process via WebRTC. Then use tarm/serial on the remote host to interact with the device.
If you want a browser on both ends there is the Web Serial API I haven't used it myself though. That locks you into only doing Chromium which might be an issue.
I've been asked to implement VPN capabilities in an existing software project on an embedded system, in order to make the device available via network to an external server while avoiding trouble with firewalls (no need for encryption, just to make it accessible).
Unfortunately, the embedded system is based on a Cortex-M4 MCU, therefore Linux, which would allow for VPN nearly out of the box, is not an option. All I've got is an RTOS and a working LwIP stack.
I've used VPNs in the past. However, my network knowledge is rather limited concerning implementing VPNs, so I'm rather stumped. As I think, I'd use the current LwIP instance for building up the tunnel connection, and the application would use a second instance for the actual network communication, while the network interface of the second instance is a virtual one (like a tap device on linux), encapsulating its low level data and tranceiving it via the tunnel connection of the first LwIP instance.
Maybe this way I'd be able to create a custom solution for the problem, but the solution should conform to any standards (as the server will be any kind of sophisticated system).
So I wonder if anyone has been confronted with a task like this, and would appreciate any hint what to do, at least a direction where to look at.
Thanks in advance!
I'm searching for a solution to work on a Windows machine with multiple NICs/networks. While working within the network of a customer I tend to get a lot of problems. I need an internet connection for several things like git/sourcesafe/development system etc. but clients often can't offer internet access. So the solution is to use a mobilephone to connect to the internet and ethernet to access the client network/database.
Windows seems to be pretty random here. Sometimes everything works, some mintues later it trys to access the internet over the clients gataway or access the database via the internet. So I end up deactivting/activating NIC's all day long.
Is there some easy way to use the ethernet connection only to access the clients network and the mobile for everything else?
From what you described I think this might help: turn off DHCP for the interface that connects to your customers network and set a static address for that (without a gateway). Then configure your other interface to use DHCP. This should set ONE default gateway (your phone) and all traffic will run through it, except endpoints in your customer's net.
BTW: You can only have one default gateway at a time, of course, but in your case the gateway that was set the latest won, so to speak.
I'm looking for a solution to find out about the MAC number of a user using asp.net website. I know you can get an IP address (don't know why but it can't be complicated) but can i find out the MAC address having the IP?
Edit: I mean programmatically (not manually) in .NET
The IP address is necessary for routing the communication between the client system requesting the information and the server. You can get it, because the IP address is pulled from a lower level in the TCP/IP stack (level 3 I believe). The MAC Address isn't necessary for any of this and hence it isn't included in the communication between the client and the server.
If your site is trusted, you can do this in IE:
http://www.devarticles.com/c/a/JavaScript/Advanced-JavaScript-with-Internet-Explorer-Retrieving-Networking-Configuration-Information/1/
I wouldn't expect it to work for any typical visitors, just users who's systems you already control, like on your local network. There may be a second way in IE if you can find a common activex that generates a guid using CoCreateGuid. It returns the mac address in part of the guid. I wouldn't bet on finding one that's commonly installed though.
no chance to get this sorry.
Even if you could it would not make sense to attempt to get this, when I access a website on the internet my MAC address never leaves my home network.
Ok if the user was on the same LAN say in a company intranet for example this could be determined by having the ip address and using command line tools like arp.
ARP stands for Address Resolution Protocol and it can be used for finding a host's link layer (hardware) address when only its Internet Layer (IP) or some other Network Layer address is known.
Java 6 has a NetworkInterface#getHardwareAddress() method which usually returns the MAC address of the computer in question. You could create a small Java applet to communicate with your web server to obtain the MAC address, though there are ways and means of spoofing a MAC address.
The MAC address you get might not be practical to use. If someone has multiple network adapters then they also have multiple MAC addresses. And it's not uncommon anymore that someone has two networks. (For example, bluetooth, regular cabled and WiFi would already be three.)
A MAC address is just for identification and it can be requested. The Address Resolution Protocol is created for this purpose. By arping you can get a MAC address. Unfortunately, this only works on local networks, not on the Internet. I think that by using IPv6, you might also have a few options. Although I think it would still be limited to just a local system.
Getting the MAC address of your visitor might be considered inappropriate and perhaps even criminal since a MAC address is generally used as an unique identifier. This information could be misused by hackers, especially when the hacker manages to gain physical access to the users network. It would allow him to impersonate the user. Your site might make some security specialists very unhappy...
At http://www.ipaddresslocation.org/find-mac-address.php there's a Java applet which they claim will work. It doesn't on my system with Google Chrome, though.
I have a similar problem (I'm using the client device MAC address as a key to target different content at different devices). This thread has been useful. Given that there seems to be no way to do this implicitly I have instead included the MAC address as one of the parameters passed by the client to the web service.
(N.B. This is not a generic answer, it only makes sense where the client and server are tightly integrated and where there is scope for passing data with the call.)
I don't think this is possible on any platform.
I have a somewhat basic understanding of network programming (and networking concepts in general) from taking a networking course in university a few years ago.
I remember being able to create a simple chat application, where the chat server is used as a central directory aware of which clients are currently online, but once a client knows another client it wants to chat with, the actual messages between them don't need to go through the server. I remember we could only test this over a bunch of LAN machines.
This C# chat program also has several comments mentioning that the program does not work over the internet: http://www.geekpedia.com/tutorial239_Csharp-Chat-Part-1---Building-the-Chat-Client.html
My question is why do these applications not work over the internet when "commercial" chat applications can. Surely, there is some way to make my computer accessible to the outer network even if its IP address is not valid outside the network of the ISP.
I see no problem with the linked-to code. The server doesn't even bind to a local address, which means it will listen for connections on all ip-addresses on the computer. There is however a comment for in the server article where the user changed the TcpListener object creation to bind to a specific address, which means clients only can connect to that specific address.
In the original server design, with using TcpListenet with only a port number, there should be nothing preventing its use on an Internet connected computer, unless there is a firewall blocking access.
Were you aware of networkComms.net and in particular the short chat example demonstrating the functionality here (It's less than 15 lines of code)? This was written specifically for people writing server-client apps in c# and given most of the problems you might come across will already have been solved and it might save you some time. This library is completely plug & play and has no issues working over the internet (as long as you can setup the necessary port forwarding where necessary).
Generally if both of your targets are behind NAT (so no true external ip addresses) and you are unable to configure port forwarding you need to look at 'TCP / UDP hole punching', quite an advanced technique.