How do Apple devices discover each other on a local network?
For example, iTunes running on my laptop is able to discover my iPhone when my iPhone is on my local network's wifi and iTunes then communicates with my iPhone. How does it do this?
I'm looking for low-level details. Since this question concerns closed-source software, I can't expect an answer that points me to source code but since the question also concerns popular devices and interaction over a network which can be monitored, I'm hoping that relatively low-level details are known. A good answer should give enough information that someone with modest knowledge in network programming could understand it and fill in the blanks.
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Im doing a research about connectivity.
But Im still wondering what the costs are for implementing a bluetooth chip or wifi module in a device that will allow me to connect to the iPhone. Does somebody here know something about these costs?
A website with these modules is also sufficient.
Thanks in advance
They're both relatively cheap. However, bluetooth is very limited when it comes to connectivity due to the half-ass job Apple did in implementing the required protocols to do something constructive with it. Wifi is limited because you have to establish some sort of AdHoc network (unless you have a wireless router in between), but after that you are basically limitless (though you have to do a lot of manual labor when it comes to implementing something useful.)
(I am not interested in pure theory, but as a practical near or mid-term possibility, say within 12-24 months.)
As a developer familiar with (but not specializing in) two major smartphone platforms, should I expect an Android library to come out which can spoof itself onto an iPhone app's GameKit-based network. It seems reasonable that a Bluetooth interface between platforms might square the opportunity to make useful applications, in the same way that modems benefited PC/Mac platforms via Metcalfe's Law.
I am looking for one of two answers:
Is this obviously not likely (e.g. because of encryption)? If so, what is the reason? Is it possible in principle, but requiring years of reverse-engineering (like SMB/CIFS/Samba)? Or is it a no-brainer and just a matter of time? Please give evidence supporting your reason.
Is there an alternative way to have direct peer-to-peer networking besides GameKit? For example, a hand-rolled network using Bluetooth or ad-hoc WiFi? It would be nice to spoof an Android device into an existing iPhone app but my main question is, can the devices speak with each other at all!
Yes, it is possible. GameKit is a protocol using TCP and/or UDP over a BNEP Bluetooth connection. It also uses a trick to identify other iOS devices using the Extended Inquiry mechanism in Bluetooth 2.1+.
I was able to simulate the EIR responses, now, someone needs to reverse engineer the GameKit protocol. This doesn't need Bluetooth, as it is also used for GameKit connections over WLAN.
If anybody can re-implment GameKit for WLAN connections, I can finish the Bluetooth version.
No, and it wont come soon or even at all... Apple pride themselves with their security features, and bluetooth connections can access private data. There will probably not be any cross platform bluetooth framework until something is agreed upon by both companies.
Bump as said by a previous answerer uses a remote server, and the data transferred is not via BT.
GameKit is Bonjour so a Bonjour (which is on IP) over Bluetooth on Android should work.
That should be possible as Bluetooth is capable of setting up tcp/ip networks. Though I have no knowledge of the IPhone SDK whatsoever, but Android does have a BluetoothSocket and BluetoothServerSocket for TCP connections.
This article, http://blog.moritzhaarmann.de/blog/2014/04/27/sorry-state-of-p2p/ written in 2014, suggest it is possible via Bluetooth LE. Available in Android 4.3+ and iOS6+
Two issues:
According to the Android Dashboard only around 30 percent of Android devices support Bluetooth LE https://developer.android.com/about/dashboards/index.html?utm_source=ausdroid.net
Communication between Android-to-Android must be done using some other method (which is not a big problem) because Android devices cannot act as server for B LE connections.
Bounjour on the iPhone gives you full access to all of the Bluetooth protocols, so you don't have to use GameKit. As for when someone will provide an easy to use iPhone to Android GameKit like framework - hard to tell.
An iPhone can already talk to any other Bluetooth device using Bonjour today.
-t
It is absolutely possible! In fact I am amazed that more people haven't done it!
Theory:
Bluetooth is just a wireless socket that you push data across and it comes across the other side, just like tcp/ip.
Practice:
http://www.techcrunch.com/2009/11/11/bump-goes-cross-platform-with-new-android-app-upgrades-iphone-version-too/
Better yet, Bump is cross-platform, which means that you can bump an Android phone with an iPhone and it should work seamlessly.
I am developing an application which identifies(find) all the systems connected in same network/LAN to share the data.
could please share with me how to identify(find) the systems which are connected in same network/LAN.
thanks in advance.
When you say all systems, I assume you mean all instances of your application? If so then the correct solution is to use Bonjour. Documentation on how to use it can be found here. Note that your app needs to be actively running on all the devices that you are trying to discover, since the iPhone does not support background apps.
If you are just talking about finding all other devices in the area then you need to resort to techniques like port scanning.
I am looking for a way to establish a wireless connection between an iPhone and a desktop client. Gamekit looks promising but all the examples / documentation only explain iPhone to iPhone.
Are there examples / documentation for an Gamekit peer on the desktop (cocoa or java)?
What are the alternatives without doing to much low level socket programming?
The iPhone emulator does not run these bluetooth p2p connections. Hence, it can only be tested with real hardware.
It is a little confusing because the GKSession reference talks only about being a way to connect peers over bluetooth, while the GKPeerPickerController states "can be configured to select between Bluetooth and Internet connections." However there's a clear note there that they're not really going to help you with internet based connections.
This is unfortunately a non-answer, but...
GameKit is an abstraction of the bluetooth and wifi networking layers, allowing a specific set of protocols for communication between two devices -- to communicate with a desktop client, you would need to replicate all of the GameKit functionality on the desktop, since there is no comparable API on the desktop. This would not be a simple undertaking.
I would highly suggest developing something over bonjour, as #Jordan suggested. Bill Dudney's project (blog article). It's a great place to start.
Citing Game Kit Framework Reference's Features paragraph:
Peer-to-peer connectivity allows your game to create an ad hoc Bluetooth or wireless network between multiple iPhones in the same local area. Although designed with games in mind, this network is useful for any type of data exchange among users of your app. For example, an app could use peer-to-peer connectivity to share electronic business cards or other data. This functionality is only available on iOS. You can also get the same functionality using Game Center.
I'm kind of curious how I should approach a problem with iPhones and communication between two phones.
I have an idea for an application that needs to send data between two known phones. The problem is that the data could be very small or very large. I want to have intermediate storage on a server and a messaging layer, but I want there to be performant means to communicate between devices for shorter, unimportant messages.
You always hear about networking and client to client communication with popular platforms and protocols, but I'm curious what people's thoughts are on doing p2p style communication with an iPhone.
I'm pretty sure it should (and can) be treated as just a simple addressable machine... so I would have to build NAT traversing network code into the iPhone itself. A thought I had would be some sort of UPnP situation where I would ask to NAT a particular port for communication to the devices... but I guess I could just as easily turn it into a polling situation.
Granted, I understand that Apple will have a "push" mechanism for developers eventually but I want to get the app out the door before hand...
Just curious about thoughts on this type of thing... any thoughts on multi-player game situations would also directly apply to (and benefit from) this question.
Have you given the WiTap sample from Apple a try? It addresses the issue of discoverability (via Bonjour) and connectivity (via basic TCP). It may not be as robust as what you are looking for, but it's worth a look:
http://developer.apple.com/iphone/library/samplecode/WiTap/index.html
Look at the docs for Game Kit in the iPhone 3.0 SDK. It allows iPhones to connect to one another locally with Bluetooth, or via wi-fi/3G. It addresses both peer-to-peer and client-server architectures. It provides unreliable and reliable links.