are there any services running by default on an iphone that would let another ip address communicate with it if the iphone's ip is known?
Yes, technically, you can. There are a couple of issues though:
Mobile IP addresses usually change
When the phone is in sleep mode, its network interface is probably not reachable.
So I don't think you can rely on that for initiating a communication with the phone.
There aren't many options out of the box on a non jail-broken phone. However, you can write your own client application that runs on the phone. It accepts or initiates the remote connection.
And in that case, the protocol is entirely up to you.
If you jailbreak your phone, you can install the OpenSSH package and have SSH and SFTP access to your phone.
I don't know exactly what you want to do with your app, but you can consider create a thread detached from the main one (using gcd) and use it to send/receive informations from a server using JSON objects for example. Sure you can use sockets and write a client or something like that.
I suggested a new thread because you can put it running forever (on a enterprise app, I don't know if Apple will approve a thread running on an App for AppStore).
I had to develop an app with a consistent client/server relationship and it was the way I got it working.
Related
I've been trying to find a solution to run an http server on an iOS device, which is accessible from anywhere as long as the encompassing app is open and running.
While searching for solutions I've come across several libraries, one of which is Cocoahttpserver https://github.com/robbiehanson/CocoaHTTPServer
While I see many people use this for setting up a local httpserver and accessing it from the same app, I am not sure if this can be accessed from a remote browser--for example my desktop browser. So here are my questions:
Is this possible? (running an iOS web server which can be accessed from anywhere, not just local network)
If it is possible, is it possible to set a static domain that will redirect to my iOS server?
1) Yes, it can be achieved. Either use the CocoaHTTPServer, which is a great library - or you can look at some tutorials on the net, like this one http://www.cocoawithlove.com/2009/07/simple-extensible-http-server-in-cocoa.html
2) Unfortunately no, because the devices will have different IP depending on the internet connection, and the domain name can be only used with one defined IP address. You could also use the Bonjour name, however it would be probably easier to use the IP address.
I'm looking to work on an iOS app that would need to send/receive data back and forth between the iPhone/iPod and a service that is running on Windows. Communication-wise, I will be using sockets.
The Phone will send/receive data to/from a Windows service (NOT a web service)
Sockets will be used as a means for communication
The iPhone/iPod will be connected to WiFi using a static IP address
The iPhone/iPod is intended to be as thin client as possible
The intention is to have the Windows Service listen for events from iPhone/iPod. Example:
Input needs to be taken from a UITextField and saved as a string by pressing a button. On the button press, an event must be fired and sent to the Windows Service over WiFi, which will then receive the event, perform a "server-side" action, and send the response back to the iPhone/iPod.
I'm pretty new to iOS development still and I know this is some more advanced stuff, but any help or resources that would help to accomplish this, I'd appreciate it.
Thanks!
This is standard network stuff not related to which platform you're using. On iOS you can do either:
1) use berkley sockets (standard unix stuff).
2) use the Cocoa wrapper for sockets (NSSocketPort etc).
3) use a framework such as MKNetworkKit (here).
I would use option 3 myself :)
One thing in your favour is that Windows machines and iPads are both little-endian, so you don't have to worry about byte-swapping (which you won't anyway if you're just sending strings).
EDIT: For windows to discover your device, you will need either a configuration setup with the IP address details, or to use Apple's bonjour service, or some custom solution.
I would like to make an application for iOS devices that would communicate with a special type of remote device using HTTP POST requests. The problem is that this device would actually act in the role of a client, while iOS device has to be the server accepting the requests. The next problem, host name and port has to be configured statically at the device sending the requests.
While I'm aware it's possible to give it a try using Dynamic DNS services and UPnP/IGD or NAT-PMP to overcome the problem with iOS device being behind the NAT router, I was wondering whether using Bonjour could simplify the problem in some way. I'm quite a newbie in networking so I'm looking for the direction and want to avoid research of Bonjour if it's not going to bring me anything.
Any other idea of how to solve the problem is appreciated as well.
I had a think about this. IMHO you can't guarantee you'll always be able to expose an iOS based service over a WAN (although it's possible) so this isn't practical.
The best solution I suggest is using uPNP to open the device behind a router to the outside world, then have it send an iOS push notification to the iPhone with the details (hostname, ip, port, etc).
The iPhone would then would then have to set up some kind of persistent connection with the firewalled device to receive data.
Bonjour is a good system to discover and connect to services/clients, but only on your local network. I don't think it is a good idea to try it over the internet.
Background
There are a lot of App Store released iPhone apps that require an IP based server on the desktop so that the iPhone can connect to the desktop as a client. For example, there are many programs that emulate a keyboard, touchpad, or Apple remote on the iPhone so that a desktop computer can be controlled over wifi. However, many of these applications get around writing their own server by requiring the user to install some VNC server variant.
Question
What is the best way to implement a secure (encrypted) IP server on a desktop (Mac and Windows platforms) that allows for simple two way message passing between itself and an iPhone client on a wifi network?
Sample Use Case
An event on the desktop causes the desktop to push a small image or text to the iPhone. An event on the iPhone causes a short text message to be pushed to the desktop. Any single event can happen at any time (doesn't appear synchronized to the user).
1st Follow-Up Question
Would this type of project be best handled using something like XML or JSON over HTTP? Or is there a better protocol, like BEEP or Bonjour(XMPP)?
What is the best way to implement a secure (encrypted) IP server on a desktop (Mac and Windows platforms) that allows for simple two way message passing between itself and an iPhone client on a wifi network?
Not sure if there is a "best" way, but much code is already available to do xyz-over-HTTPS (TLS/SSL). In that case, the "xyz" can be any web-based message exchange protocol, such as XML, JSON, etc. via REST or SOAP, etc.
If you want to be able to push events to a non-jailbroken iPhone you can't do it other than via Apple's Push Server which causes a notification to the client program if it is running or otherwise displays an alert of some kind to the user.
Typical architecture has those notifications handled by the client program as an indication it should go and get some data from the server - Apple insist we do not regard the notifications as trusted delivery.
I suggest a read of this article on using Bonjour and local networking, whilst it's iPhone to iPhone it should apply to desktop OS/X also.
Is it possible to connect a socket between two mobile devices (iPhones) over the internet?
I am trying to discover the IP of each device and connect directly. I know it can be done with Bonjour but that only works on local networks. I need a high speed connection between two devices over the internet.
Thanks.
If you had both the IP's and they were both routable, it should be possible. I'm not sure though if the IP's given out by the 3G network are routable. If you are using WIFI, the IP you get is almost certainly not routable. Assuming you have a routable IP though, it should be possible.
The trick is just discovering the IP of the other device. The best way to do that would probably be to have each device register its IP with a web service when your app starts up, then query that service to find the IPs of other devices.
It might get a bit tricky managing "unregistering" IPs when the app is closed or when an IP changes though, but it should be doable.
ETA:
If you have a server that they can both connect to, you should be able to implement a solution using that server (i.e. without the phones actually directly connecting to each other). This would avoid the issue of having routable IPs for the phones.
As for how to bridge the sockets together - your server program would basicly work like an old-school phone switchboard operator. You'd have some kind of registration & discovery protocol built into the server software that would allow a phone to register itself with the server, query a list of the other phones currently connected to the server, indicate which phone it wants to talk to, and accept connections from other phones.
Once it knows who wants to talk to whom, your server software would connect the two together by reading from one phone's socket and writing that data to the other phone's socket.
Only a suggestion, but if you can get each of them to connect to a third site, you'll then know the address of each. Send the address of phone A to phone B (and/or phone B to phone A) and then have them connect as you see fit.
Have you looked through all the 3.0 features? Specifically peer networking (the existence of which is public).
WiFi routers often have a feature called "Port Triggering" which allows internal hosts (in this case an iPhone) to inform the router that they would like to have a connections on particular port forwarded to them. I have no idea if the iPhone supports this protocol.
For IP lookup you may consider using DynamicDNS if the two hosts are known ahead of time OR as stated above a custom web service if they are not (i.e. friends exchanging hostnames vs. strangers discovering each other)
This is an old thread, but I just came across it. You could use a STUN server (or NAT-PMP) to get the public IP address/port combo and then SMS it over to the other phone. So long as you open a listening port on the first device, then your second device can just connect directly using the publi IP address/port you sent to it in the SMS (SMS push registry can automatically wake up your app on the second device to do this)
I have run into this issue with an app I was developing. I was trying to connect to a PC cell card from an iPhone. The problem is that AT&T doesn't enable mobile termination for iPhones so it is physically impossible for two phones on an AT&T network to connect to one another. This is straight from an AT&T antenna engineer.
I was able to get this to work by having the iPhone VPN into a server and then connect to the PC cell card but other than that, it wouldn't work.
I have a very strong feeling (but no evidence) that the iPhone address is going to be non-routable. Of course it actually depends on the operator but AT&T give out 10.x.x.x addresses.
Apple have sample (desktop) code that uses Bonjour to implement portmapping on a WiFi router that supports UnPnP.