What problem does my-devices.net solve?

Many embedded devices are equipped with a built-in web server for configuration, control or monitoring purposes. This would be a great tool for remote access to the device. However, access to the device's web server from a remote location is rarely possible. Embedded devices in the field are often connected to private networks behind NAT routers or firewalls. This is especially true for consumer electronics devices like set-top-boxes, home automation/networking devices or smart metering devices, which are typically located behind a NAT broadband router. Even devices connected to a mobile network such as GSM/GPRS or UMTS in most cases do not have public IP addresses and thus are not directly reachable. Existing solutions to this problem like Virtual Private Networks (VPNs) or NAT port forwarding are complicated to setup and operate, and don't work in all cases.

How does my-devices.net work?

my-devices.net uses a simple extension of the HTTP protocol known as Reverse HTTP. Reverse HTTP is based on a simple modification of the well-known and proven HTTP protocol that drives the internet. The only difference to HTTP is who is setting up the network connection which is used for sending HTTP requests and receiving their responses. In HTTP, the client (web browser) is responsible for opening a connection to the web server, over which it then sends the requests. In Reverse HTTP, it's the server that sets up the connection. Since the Reverse HTTP server does not know its clients, and would not even be able to create a direct network connection to each client (as clients are usually behind a NAT router or firewall), the Reverse HTTP server opens a connection to a special server called the Reverse HTTP Reflector. For this to work, the Reverse HTTP Reflector must be accessible over the internet. Once the connection between the device and the reflector server has been established, the reflector uses this connection to send HTTP requests to the device. Where do this HTTP requests come from? The Reverse HTTP Reflector also contains a standard HTTP server, which accepts requests from clients (web browsers). These requests are then simply forwarded to the device, using the device’s Reverse HTTP connection. Setting up the initial Reverse HTTP connection between the device and the reflector server is almost always possible as long as the device can access the internet. It even works through a HTTP proxy server because the initial Reverse HTTP message exchange is plain HTTP(S).

In a typical usage scenario, more than one device will be connected to a reflector server. Therefore, when the reflector receives a HTTP request from a client, it needs to find out to which device the request must be forwarded. The domain name system (DNS) is used for that purpose, by giving every device a unique domain name (e.g.: device1.my-devices.net). This requires setting up a wildcard DNS record in the DNS server which resolves all requests for *.my-devices.net to the reflector server reflector.my-devices.net. The reflector server can then use the Host header in the HTTP request together with an internal table to associate the request with a device and forward it appropriately.

Is my-devices.net secure?

Short answer: Yes! Long answer: Three features make my-devices.net secure. First, both connections, from the device to the reflector server and from the client browser to the reflector server are encrypted using SSL/TLS. Second, the device does not need to have any ports open. The reflector server (and only the reflector server) can send requests to the device only over the Reverse HTTP connection initiated by the device. Third, any requests to the device over the reflector server require authentication with username and password.

How can I connect my own devices to my-devices.net?

There are three ways to connect a device to my-devices.net. First, if the device is using the POCO C++ Libraries and the web server provided by the POCO libraries, then making the device connect to my-devices.net is as simple as linking another library and adding a few lines of setup code.

Second, devices using almost any web server can be connected using our Reverse HTTP proxy server software (PTTHProxy). This software will set-up a secure connection to the reflector server and forward incoming requests to the device's web server. The Reverse HTTP proxy server can run directly on the device, or it can be run on a separate device or PC.

Third, for devices that are not capable of running the standard Reverse HTTP proxy software (smaller, microcontroller-based devices with only a few KBytes of RAM), the Reverse HTTP protocol can be implemented directly in the device's firmware.

My device has a REST or SOAP API. Can I access it with my-devices.net?

Yes, the reflector server transparently forwards HTTP requests to device, so my-devices.net can also be used to make your device's REST or SOAP API available remotely. In fact, this makes my-devices.net a great solution for integrating remote devices with enterprise applications. HTTP requests sent to the device via the reflector server must include authentication information, either in the form of a session cookie or a special authentication header, so your client software must support that. Please see the API documentation for more information regarding authentication.

Can I run my own reflector server?

Yes. Customers wanting to operate their own reflector server can license the server software from Applied Informatics. The server software is fully customizable and extensible through plug-ins and web service APIs, enabling building customer-specific device management solutions on top of it.

Is there an API?

Yes. Here is the REST API documentation.

Can I learn more about the technology?

Read our white paper to learn more about the technology behind my-devices.net or contact us for more information.

Frequently Asked Questions

• What problem does my-devices.net solve?
• How does my-devices.net work?
• Is my-devices.net secure?
• How can I connect my own devices to my-devices.net?
• My device has a REST or SOAP API. Can I access it with my-devices.net?
• Can I run my own reflector server?
• Is there an API?
• Can I learn more about the technology?

White Paper

Read our white paper to learn more about the technology behind my-devices.net.