I'm working on an application that downloads some data from the internet using NSData's initWithContentsOfURL method. At startup I'm using some code from Apple's Reachability sample to check if a wifi connection is available; if not, then the app just shows an error message and refuses to really start (as requested by my client). All is working fine on iPod and iPad, but on iPhone, my client reports much, much slower download speeds, unless he turns on airplane mode, in which case download speeds are on par with iPod / iPad speeds. So it seems that even though a wifi connection is available, the iPhone is probably using the cellular network to download the data. Which is really weird. Does anyone have any idea about what I might be doing wrong?
I believe your answer is SCNetworkReachability which you already have access to since you are using Apple's Reachability code.
The SCNetworkReachability API allows an application to determine the status of a system's current network configuration and the reachability of a target host. One of the flags returned by the API, kSCNetworkReachabilityFlagsIsWWAN, will tell you if a network connection to the target host uses the carrier network. The Reachability sample code shows how to determine the active network connection.
You could also use this to enforce WiFi if that's what you want.
Have a look at UIRequiresPersistentWiFi
Related
Network Link Conditioner is the develop tool provided by Apple, but seem like not work together with the other tool Reachability.
Network Link Conditioner is the tool to simulate 3G/Edge/Wifi network cases.
Reachability is to recognize the different network cases.
Anyone has such experience to make them work together ?
You shouldn't have any issue with Reachability since it really just tells you whether or not you have a network connection, not how well it is functioning. The only difference is between Wifi and Cellular, not between different speeds or cellular connections.
Reachability doesn't test the speed of the network to determine what kind it is. Reachability is about availability of interfaces (airplane mode vs. not, wifi on / off).
Important note:
A remote host is considered reachable when a data packet, sent by an application into the network stack, can leave the local device. Reachability does not guarantee that the data packet will actually be received by the host.
From Apple's SCNetworkReachability documentation.
First and foremost,
I am looking for a resource to use Private API's.
this is an enterprise application and will never go to the app store
I need to take as much configuration out of the users hands as possible.
That being said, I have a device that an ipad will be connected to and communicate with via an adhoc wifi network supplied by the device. the ipad connects to this device and sends raw data to it via socket connections. I also need to connect to the internet for data syncing.
80% of the time, the ipad will be connected to this adhoc wifi device. Management software on the ipad does not allow the user to adjust wifi settings so I am trying to make sure I am connected to my device without limiting my server syncing. I know I can determine the connection using apples Reachability class, this is not what i am looking for. I need to use BOTH 3g AND wifi.
Is there a way to enforce this in code? Or is there a resource for the private API's that I can look at to find a way?
This will be in iOS 5 and the most preferable method would be to just route my http requests via some private api method to use 3G and let the socket requests use wifi to the adhoc device.
code samples would be awesome, links / class names to research would be very much appreciated.
and once again this is not going into the app store, it is an enterprise app
the resolution i found was to assign an ip in the privately assigned ip range the ipad uses (169.254.x.x) to the adhoc device then let the ipad determine an ip. Then see if i can open a socket connection to the device (to determine if its available) and then issue a print.
Going this route, i am still able to use 3g data as well as communicate with the device via wifi.
My iPhone connects over adhoc wifi to a wifi sensor module.
The challenge is to code an app that uses this sensor module. But I'm not sure what specific API's to use to best architect this implementation.
I've started looking into the CocoaAsyncSocket class as it seems to be an appropriate tool for such use.
Does the user always have to manually connect to the adhoc wifi device? (through the Settings app) or can my own app handle the searching, making, and breaking of the wifi connection?
I doubt iOS lets me programmatically toggle whether Wifi is on/off.
Once the sensor data is being received, what container would best handle the stream?
For example, on other platforms, I coded a rotating queue buffer.
Thanks for your input.
Edit: The protocol in question is straight CSV formatted ASCII. Not HTTP, FTP, etc. Just raw data. The app is to simply open a port on the connected IP, and read/write.
Your application cannot turn wifi on/off, or select a wifi network.
Without more information on what protocols this wifi sensor module speaks, it will be impossible for anyone to give more than vague recommendations. If the module can serve data over an http connection, that would probably be ideal. If it requires your software to open a connection on a specific port and communicate over something other than http or ftp, your job will be a bit more complicated. CFNetwork and projects derived from it's usage, such as CocoaAsyncSocket which you mentioned. You can see another implementation of an HTTP connection over CFNetwork in ASIHTTPRequest, that may help as a reference for handling download streams, queuing operations, etc.
As for storing the data, again it's hard to give any concrete recommendations without more information. If you want to store the data to the filesystem of the iOS device, NSData will probably meet your needs. If you need/prefer to use a queue for buffering data, there is a simple category on NSArray which provides queue semantics. The link to CHCircularBuffer in that SO article is dead, but this github project appears to have it.
edit: Here is the official version of the CHDataStructures. I don't know if it's an improvement over the previous link, but it appears to be updated for the more recent iOS SDK.
Add the SSID of your wifi ad hoc networks in settings. When you see the SSID of the network, click the arrow and choose connect automatically. After this, the phone will automatically connect whenever it comes in range. After this, the two devices can communicate using regular socket APIs.
I want to create an iPhone application that can call web services on a computer, and then upload those files over the iPhone 3g connection. Is there an elegant way to do this?
I tried connecting the phone to local Wifi, but connecting to Wifi disables 3g, even though the Wifi is local network only.
I assume the same problem would arise if I could network the phone with the computer via bluetooth.
Any other ideas? The purpose is to go up to a special demo PC we created, pull some data off, then upload to the Internet, all within proximity of the machine. Unfortunately, it appears that I can't use one connection for pulling data, and another for pushing.
Your assumption is correct. When connecting to both 3G and Wifi, the Wifi connection will be used. Sounds like your local network has no route to the Internet. Perhaps that could be fixed.
Apple does not prefer its iPhones to be used as routers.
If you're working on something that will not be distributed through the App Store, you may have some success looking at "tethering" applications and their source code, which can be found by some clever Googling.
I am working on a educational related apps. My app functionality is working well when the WIFI is connected otherwise it is getting crashed.
In my app I am connecting with the server using NSURLRequest class its working.
the download also not having any problem if the wifi is available.
problem rectification: I have to know weather the my app device is connected with external network or not.
So, how can I know my app is connected with the wifi or not?
The following link consists source code, in which it consists how to check the reachability. That means the wifi or any network is connected of not.
http://developer.apple.com/library/ios/#samplecode/Reachability/Introduction/Intro.html
Apple provides sample code called "Reachability" to detect when the network is available. That would be a good starting point, though a quick Google should locate some alternatives.