What NuGet packages should be installed to enable Xamarin cross-platform mobile devices to use cellular data to access the Internet and reach app services?
Talking it a step forward, I did a simple TCP test to see if a connection was actually possible:
'TcpClient c = new TcpClient("52.173.xx.xxx", 443);'
It was when looking at the TCPClient attributes even though the profile was Unknown.
Related
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.
How should I access a serial port on a client PC from a webpage in a production environment?
Ideally coded in C# and client Blazor, but any suggestions very welcome.
Any example applications on the web?
Web Serial API and Javascript option works in Chrome if you enable the experimental option: "Experimental Web Platform features" : Enables experimental Web Platform features that are in development. – Mac, Windows, Linux, Chrome OS, Android. #enable-experimental-web-platform-features
https://bugs.chromium.org/p/chromium/issues/detail?id=884928
Being experimental precludes use in a production environment till it is formally released (experimental licence must be renewed every 6 weeks, expires in September 2020 and the functionality can be removed by Google at any time.)
So far the only solution I can think of is to create an ASP.NET Core Service application that must be installed on the client and the webpage application must connect to this local API to use the local serial port.
Any technical issues that would prevent this service approach from working? Other approaches I should consider.
The web application will be designed to interface with a central/upper arm blood pressure monitor that outputs large XML (or JSON) results after each measurement. The measurements will be saved into a "cloud" service for research and patient monitoring.
Thank you in advance for suggestions and comments.
I am wondering what is suitable for my case, using espeasy or Tasmota. I know espeasy is using http requests and Tasmota is using mqtt.
I want to control my sonoff devices by a raspberry pi that is acting as a home automation hub, and it in turn send updates and receives commands from AWSIoT platform. For interacting with AWSIoT platform, it uses mqtt.
What are the pros and cons of using either? and will it cause problems if I control several sonoff devices with http, while using mqtt for AWSIoT? or better use mqtt for all AWSIoT and sonoff?
I am not an expert on the topic but have tried a few things and got some insight for you on why to prefer MQTT over HTTP.
Security. Remember that the 'S' in IOT stands for security. Joking aside. I have not seen an option for encryption (HTTPS) of the HTTP-traffic for tasmota. (May the internet correct me if I am wrong) So choosing HTTP means your user/password (which are not a requirement but should totally be used) are transfered via URL query parameters as plain text. MQTT has built-in mechanisms for encrypting the traffic. I haven't been able to get that working in my network but I'm trying.
Flexibility/Reliability. With MQTT/Tasmota you have the ability to implement automations that do not rely on your home automation hub by having your devices publish MQTT-messages directly to each other for interaction. For example if you would like to implement an emergency off button that turns multiple devices off you do not want that to rely on your home automation server. Doing this with HTTP 'could' be done too but requires all users/passwords of all the devices to reside not only in your home automation hub but also on other single devices.
Networking. Adding new devices to your hub should be as easy as possible. In matters of HTTP your home automation hub has to know how to find your devices via IP-addresses or domain names since it has to resolve a URL. When using MQTT you just connect your tasmota devices to your broker and use their topic in the home automation hub. The devices do not even need to have a static IP or reachable domain name of mDNS name of any sort. That's in an essence what makes pub/sub for IOT so interesting in the first place.
Existing support. Before building your own home automation solution be sure to check out home assistant (my favorite) or any of the other home automation solutions if they fit your need. Do not reinvent the wheel. A tipp for home assistant: Do not use MQTT auto discovery in combination with tasmota. This is the only thing that has not worked out for me. Manually registering devices works reliably.
Hope that helps. If you still prefer HTTP checkout the app "Tasmota control".
I am writing a chat application in QML/C++. I have already implemented an option to chat locally (with people in the same network) and I am currently working in implementing a bluetooth chat option.
However, one early user of my application suggested me to implement an ad-hoc based chat option that would communicate each device directly (without the need of a router, in other words, peer-to-peer). This feature would be very useful if the user(s) are located in a place without an internet access point, say a music festival or in an event.
My application uses the Qt framework and it has the necessary tools for me to implement this feature, however, I am a hobbyist programmer and I don't have a lot experience dealing with network connections.
Do you know any way to implement this ad-hoc, peer-to-peer feature? (or know any helpful websites/links).
Thanks in advance,
Alex.
You can use TCP or UDP protocol for your chat application.
TCP = connected protocol
UDP = "broadcast" protocol, more speed
Example here :
http://qt-project.org/doc/qt-5.0/qtnetwork/network-chat.html
Or here : http://qt-project.org/doc/qt-5.0/qtnetwork/examples-network.html
Yekmen
i want to read MAC address of machine from Adobe AIR. I am using flex 3 and AIR 2.
how can i do this
the main purpose is i want to install that product in only one machine
var ni:NetworkInfo = NetworkInfo.networkInfo;
var interfaceVector:Vector.<NetworkInterface> = ni.findInterfaces();
Taken from the Network Info sample in the desktop version of Tour de Flex.
As far as I can tell, you cannot do it with Flex/AIR alone - you can however use the NativeProcess API to communicate with a Java/C program that can do this for you.
If you want to limit your application to just one machine, why don't you just install it manually without giving away the setup file - is it a remote machine? Even in that case you should be able to do a remote installation, right?
The answer "track the combination of IP address and user ID" won't satisfy my (very similar) needs. If the (laptop) computer is moved across WiFi domains, its IP address will change. If the computer is on a commerical IP provider, the IP address can often change without warning or notice.
My users don't want to deal with such problems. They don't even want to know that these problems exist!
The binding of MAC address and user ID can be done at installation time. It's not perfect, but it's pretty good.
Of course what we need is an implementation of public-private key...
Oz