Any way to speed up WWW requests?

I'm moving a multiplayer application of mine from XNA over to Unity so that I can make use of the web player. To make things work with the Web Player, it seems I have to use the WWW class instead of HttpWebRequest. My tests are showing that accessing the exact same page from a Unity application takes 10 times longer using WWW than it does using HttpWebRequest. Is that to be expected? Is there anything I can do to improve WWW's performance?

In my specific case, the WWW request takes about 450 ms (around half a second) to fully execute, while the HttpWebRequest is taking 47 ms - less than half of a tenth of a second!

WWW is also encoding the download into proper objects - are you accounting for the post-download initialization in your comparison?

I’ve had some success increasing WWW request performance by building the POST data myself rather than using the WWWForm object:

	private string generatePostString(){
	//MW: Generate a random salt for this request
	System.Random random = new System.Random();
	int randomNumber = random.Next(0, 9999999);

	//MW: hash the salt and secret key
	string salt = randomNumber.ToString();
	string hashedKey = Md5Sum(mSecretKey + salt);
	System.Text.StringBuilder sb = new System.Text.StringBuilder();
	sb.AppendLine("hashedKey="+ hashedKey +"&salt="+ salt +"&deviceType=5&bindingVersion=0.1");
	foreach (DictionaryEntry item in mParameters){
		//MW: TODO We need to distinguish between data types and correctly handle each one.
	return sb.ToString();

private byte[] convertPostStringToData(string postString){

	//MW: convert the string into a byte array
	ASCIIEncoding encoding = new ASCIIEncoding();
	return encoding.GetBytes(postString);

Also, I suspect the additional time for a WWW request is because it has to load the crossdomain.xml for every request which is pretty annoying.