Is it somehow possible to tell the browser to choose a specific interface and ignore the Windows routing table?
I have the following problem:
I have a PPP dial-up, where I have to access some https websites, if I make my standard gateway point to this PPP interface, I can access the website.
But I don't want to add a specific route, as I connect to different devices, and all have different IP Addresses, so it is also possible that my local LAN Interface, where I have my internet access, has the same IP Address as the remote https address I need to connect to.
So I think the only way would be to somehow tell the browser to use a specific interface for all the traffic. Is this somehow possible, or possible with VB.net programming?
"Is it somehow possible to tell the browser to choose a specific interface and ignore the Windows routing table?"
No. As an application, the browser relies entirely on the OS's network stack to establish communication.
The point of a network is to allow many-to-many communication. So, if you do it right, you can use a single network adapter to communication with hundreds or even thousands of other nodes at the same time.
You could use a NIC to establish a PPPoE session to the Internet while at the same time communicating with your local network. However, this in turn requires you to connect the modem to the LAN as well which is not a good idea - you should either use two separate NICs or an Internet router.
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I have set up a LAMP server on a Raspberry Pi on my home network. I would like to expose the pi to the internet by opening up ports 22 and 80 on my router so i can ssh into it as well as use any web services i set up on it.
This is a little pet project I'm using to learn more about networking, server setup and linux in general - with only a cheap RPi which i can wipe and start again easily anything goes wrong. I do plan to put it on a separate subnet to the other devices on the home network, just in case.
(Yes, i know this is a little much for a raspberry pi - this is just a learning exercise and a proof of concept before i throw money at this to build a rig for it)
My understanding is that SSH is already secure, so i don't have to worry about my username and password being seen across the web when i want a terminal session.
My concern is that if i send anything to a web service (such as a wordpress or phpmyadmin password) it'll be clear to see on the web. How can i stop this?
My plan was SSL, but from what I've read, an SSL certificate needs a domain name for a certificate to be issued by most places. When all I'll be doing is pointing to a static IP from my ISP on the devices I'll be using.
The other use i have planned for it is as a mysql server for my kodi boxes to use for the library data so my devices can share data (the videos live on another server running windows). So other devices on a local network need to be allowed access to mysql easily without the silly level of security the internet-side requires. I assume this will be easily possable alongside my other use cases as I'd not be opening the port for it on the router and the only things that would access msql are local network devices, and services on the mysql host itself
Are any of my assumptions or conclusions wrong?
Are there any better ways to achieve what I'm after than what I'm describing?
Is there a preferred way to interact with the Pi if i just wanted it to set off a specific script? (say send a wake-on-lan packet to a specific computer)
Is there a way for me to have the web server onllly communicate with specific devices that i have the appropriate keys/certificates loaded onto so that i can be certain that I'm the only one with access?
Are any of my assumptions or conclusions wrong?
Using a username/password combo for SSH is probably secure enough, but it's generally more secure to use a public/private SSH key pair.
Your assumptions about MySQL seem sound. Just make sure to have some authentication on the server just in case you have a nosey houseguest on your WiFi. :)
Are there any better ways to achieve what I'm after than what I'm
describing?
A couple options that come to mind:
You could generate a self-signed certificate for the web server and then manually copy that onto your client devices. I think this would allow you to get around the requirement for a domain name.
You could set up a secure VPN into your home network. This way you wouldn't have to expose your web/SSH servers to the world.
Is there a way for me to have the web server only communicate with
specific devices that i have the appropriate keys/certificates loaded
onto so that i can be certain that I'm the only one with access?
The VPN option mentioned earlier would allow you to do this.
You could restrict access to the Apache server to only devices with specific client certificates: https://stackoverflow.com/a/24543642/2384183
WebRTC signalling is driving me crazy. My use-case is quite simple: a bidirectional audio intercom between a kiosk and to a control room webapp. Both computers are on the same network. Neither has internet access, all machines have known static IPs.
Everything I read wants me to use STUN/TURN/ICE servers. The acronyms for this is endless, contributing to my migraine but if this were a standard application, I'd just open a port, tell the other client about it (I can do this via the webapp if I need to) and have the other connect.
Can I do this with WebRTC? Without running a dozen signalling servers?
For the sake of examples, how would you connect a browser running on 192.168.0.101 to one running on 192.168.0.102?
STUN/TURN is different from signaling.
STUN/TURN in WebRTC are used to gather ICE candidates. Signaling is used to transmit between these two PCs the session description (offer and answer).
You can use free STUN server (like stun.l.google.com or stun.services.mozilla.org). There are also free TURN servers, but not too many (these are resource expensive). One is numb.vigenie.ca.
Now there's no signaling server, because these are custom and can be done in many ways. Here's an article that I wrote. I ended up using Stomp now on client side and Spring on server side.
I guess you can tamper with SDP and inject the ICE candidates statically, but you'll still need to exchange SDP (and that's dinamycally generated each session) between these two PCs somehow. Even though, taking into account that the configuration will not change, I guess you can exchange it once (through the means of copy-paste :) ), stored it somewhere and use it every time.
If your end-points have static IPs then you can ignore STUN, TURN and ICE, which are just power-tools to drill holes in firewalls. Most people aren't that lucky.
Due to how WebRTC is structured, end-points do need a way to exchange call setup information (SDP) like media ports and key information ahead of time. How you get that information from A to B and back to A, is entirely up to you ("signaling server" is just a fancy word for this), but most people use something like a web socket server, the tic-tac-toe of client-initiated communication.
I think the simplest way to make this work on a private network without an internet connection is to install a basic web socket server on one of the machines.
As an example I recommend the very simple https://github.com/emannion/webrtc-web-socket which worked on my private network without an internet connection.
Follow the instructions to install the web socket server on e.g. 192.168.1.101, then have both end-points connect to 192.168.0.101:1337 with Chrome or Firefox. Share camera on both ends in the basic demo web UI, and hit Connect and you should be good to go.
If you need to do this entirely without any server, then this answer to a related question at least highlights the information you'd need to send across (in a cut'n'paste demo).
What I want is, basically, to create a connection between two different computers on same local network. But i want to do this by computers' local IP's. (like 192.168.2.23 etc)
This must be a totally local connection. no TURN or STUN Servers. I am not sure if this is possible. Because there are not much documentation/example/information about WebRTC.
So, how can I create a connection from my computer to another one just passing its local IP as parameter?
Update: To be more clear; imagine there is an html page contains some code that activates my camera and audio services. and another -almost same- page is open in other computer. Waiting a connection request... And there is a textbox in my page to type an IP belongs to other computer on my local network. type 192.168.2.xx and bingo! i have connection between me and other computer.
I want this process as IP based, because there may be more than 2 devices on the network. And all of them are possible devices to create connection. So i need to reach them by their IP's.
Any example code or explanation would be great! even if it tells that this is not possible.
Thanks
Peer discovery is a vital part in any WebRTC application. It's an expensive term for saying: "Hi, I'm computer 4 and I want to talk to you!".
See it as calling a friend over the phone. You need to dial his number first.
This part is not defined in the WebRTC standards. You need to implement this logic in your application. Once you know who you want to call, you need a way of exchanging vital information. This is called signaling, like flo850 put in his answer.
Signaling is needed before any peer-to-peer connection can be set up.
To come up with an idea for your use case of 7 devices in a LAN.
If you have these devices connected to for example a WebSockets server and are in the same channel.
The WebSockets server can be written to route messages to specific receivers.
Devices connected to the channel often are identified with some kind of ID, imagine you use the device's IP.
When you want to talk to computer 4 with IP 192.168.0.4 you send the exchange messages (signaling) on the channel to the receiver with ID, the IP of the device you want to connect with.
How to send the signaling (offer, answer) is described here with example code.
Hope this helps
Users usually sit behind NATs; that's why ICE concept implemented in WebRTC.
If both users are sitting behind same NAT; you can skip ICE servers by passing "NULL" parameter value over "RTCPeerConnection" constructor:
var peer = new [webkit|moz]RTCPeerConnection ( null );
Now, browser will use "host" candidates, also known as "local" candidates.
you still need a signaling server. During the ICE candidate search, your clients will exchange their local ip through this signaling server
For an iOS app I am developing, I want multiple phone to connect to each other and be able to voice chat between those devices.
I have it working when both devices are on the same network. This was quite simple and most of the stuff I want to do, is possible.
But now I am adding internet support, which is quite a hassle. I'll first try to explain how I want to match the devices, using a small webservice I set up.
Server
Start a new GameKit session, with session-mode GKSessionModePeer
Find the "Peer ID" of the server on the session I just created
Create a new CFSocketRef on an free port and keep it ready to accept connections
Send Peer ID and Port number to my webservice, running on an external server.
WebService
Webservice receives the information and stores it together with an ID and the IP address of the client in a database.
Send ID back to Server, which displays the ID
Client
When the user chooses to use the "Online" feature of GameKit to search for games, I ask the user for an ID (where the user should input the ID the server receives).
Client connects to the webservice supplying the ID. The webservice returns the information about the session (IP, PORT, Peer ID) of the server.
The user tries to connect to the IP address, with the port information and set up an input and output stream with the server.
This does not work ofcourse, because my network does not allow incoming connections and a random port (from an external network).
But now the question is, how do I solve this? I want to be able to set up a peer to peer connection between 2 devices, those devices could be on the same network, but also on separate networks.
Is there a framework, example or anything showing how to do this? I want to be able to send data from device to device, without sending it to a server first.
I'm not aware of any frameworks that do this. I do however have a lot of experience with p2p networking across multiple networks.
One important rule I learned: when communicating between networks, don't create a direct connection unless necessary. There are just too many factors that can (will?) cause issues, such as firewalls, NATs, etc.
Sure, you can let the connection try first. You can try to connect to the given IP addresses*, but in most cases it will fail. Even when using UPnP and NAT-PMP, you'll find that in a lot of cases (more than half?) you won't be able to accept incoming connections at all.
So make sure to have a backup plan. Make a network layer abstraction that doesn't only listen(), but also connects to a server. That way, when you can't connect to the IPs* of the client, you simply setup a connection via the server and the network abstraction takes care of it all.
Let me reiterate the above: don't rely on incoming connections only, always have a backup plan.
* I write IPs because clients can have multiple local/remote IPs. Always iterate over all these IPs when connecting. Example: my phone has 2 local IPv4 addresses (10.0.0.172 and 10.8.0.2), and an IPv6 address ([2001:x:x::6]). Of these three addresses, only the IPv6 address is publicly reachable, and the two IPv4 addresses are on different subnets so whether you can connect to them depends on the subnet that the other client is on. Always try to connect to both, and fall back to a server-proxied connection when it fails.
** I mentioned IPv6, yes. Let's not forget that IPv6 is not limited by NATs, unlike IPv4, and this means that you're far more likely to get a good connection via IPv6 than IPv4, if supported.
I have a mini API that is only for an app I have built. The API service is on a separate domain to my app. I make jsonp calls to it and receive json in return.
Therefore I only want my app to be able to access it. Can I just list a series of IP addresses for my app and allow them? Is there a better way to stop requests from anyone else to my API?
The best way to implement IP-based filtering would be at the web-server level. Here's a brief introduction to access control with Apache. If that happens to be your web-server.
If the IP stays the same throughout time, yes this is a valid idea. Another way would be with an id and a key, if you expect further usage from other (dynamic) ip adresses.
What operating system is the API service running on? If it's Linux, look into iptables to only allow a certain IP to access a specific port.
Honestly, I wouldnt go with an IP based solution. While it may work in the short term, it will make things hard in the future. For example, what if your ip provider decides to do a reset? Most likely (unless you have explicitly established the need for static ip with your provider) your ip will change. Then your program will error and you wont know why (or worse, you wont know that a computer is now disconnected). Furthermore, if you want to add machines, think about managing 1000 ips....yikes! The 'right' way of doing this would be to authenticate the machines using some other scheme (user/pass, pki, etc.)