ios组播，模拟器可以发送，接收；真机只能接收，求解

Question

//初始化udp
GCDAsyncUdpSocket *tempSocket=[[GCDAsyncUdpSocket alloc] initWithDelegate:self delegateQueue:dispatch_get_main_queue()];
self.udpSocket=tempSocket;

//绑定端口
NSError *error = nil;
if (![self.udpSocket bindToPort:3456 error:&error]){
    NSLog(@"绑定端口失败");
    return;
}

//发送广播设置
if(![self.udpSocket enableBroadcast:YES error:&error]){
    NSLog(@"广播使能设置失败");
    return;
}

//加入群里，能接收到群里其他客户端的消息
if(![self.udpSocket joinMulticastGroup:@"239.55.55.55" error:&error]){
    NSLog(@"加入组播失败");
    return;
}

//启动接收线程
if(![self.udpSocket beginReceiving:nil]){
    NSLog(@"启动接收线程失败");
    return;
}

    NSData *msg = [@"get" dataUsingEncoding:NSUTF8StringEncoding];
[self.udpSocket sendData:msg toHost:@"239.55.55.55" port:3456 withTimeout:-1 tag:10];

Answer 1

http://bbs.csdn.net/topics/391964821