Establish synchronous connection with the sever in swift - iphone

Question

I have the following function to establish the connection synchronously with the sever on a particular IP and port, send a JSON request to sever and return the server's response to the calling function.
func connserv(jsonString:NSDictionary){
var abc: NSDictionary?
// This is the action performed when clicked on the Connect button on the connectivity screen
println("------------------Function connserv")
let prefs = NSUserDefaults.standardUserDefaults()
var IP: AnyObject = prefs.objectForKey("IP")!
var port: AnyObject = prefs.objectForKey("Port")!
println("IP in Connection : \(IP)")
println("port in Connection : \(port)")
prefs.synchronize()
let localizedModel = UIDevice.currentDevice().localizedModel
let model = UIDevice.currentDevice().model
let devicesystemVersion = UIDevice.currentDevice().systemVersion
println("HTTP request jsonString : \(jsonString)")
var request = NSMutableURLRequest(URL: NSURL(string: "https://\(IP):\(port)/")!)
var response: NSURLResponse?
//var request: NSURLRequest = NSURLRequest(URL: NSURL(string: "https://\(IP):\(port)/")!)
//var response: AutoreleasingUnsafeMutablePointer<NSURLResponse?>=nil
var error: NSError?
var err: NSError?
request.HTTPBody = NSJSONSerialization.dataWithJSONObject(jsonString, options: nil, error: &err)
request.HTTPMethod = "POST"
request.setValue("application/json", forHTTPHeaderField: "Content-Type")
request.setValue("application/json", forHTTPHeaderField: "Accept")
// send the request
println("HTTP request : \(request)")
var e: NSError?
NSURLConnection.sendSynchronousRequest(request, returningResponse: &response, error: &e)
debugPrintln(response)
println("response-------------------------> : \(response)")
}
When the above function executed, server does not receive any thing and gives the following error:
HTTP request : <NSMutableURLRequest: 0x7c8bb240> { URL: https://144.1.1.45:9299/ }
2015-04-07 11:16:59.661 MyApp[996:24843] NSURLConnection/CFURLConnection HTTP load failed (kCFStreamErrorDomainSSL, -9813)nil
response-------------------------> : nil
2015-04-07 11:16:59.663 MyApp[996:24600] Unknown class UIAlert in Interface Builder file.
I want to return server response (variable response) to the calling function of the connserv function. Please help me to achieve this requirement.