public void Roundtrip()
{
var psk = new PreSharedKey().Generate();
var plain = new byte[] { 1, 2, 3 };
var plain1 = new byte[3];
var plain2 = new byte[3];
var insecure = new MemoryStream();
var secure = new Psk1Stream(insecure, psk);
secure.Write(plain, 0, plain.Length);
secure.Flush();
insecure.Position = 0;
secure = new Psk1Stream(insecure, psk);
secure.Read(plain1, 0, plain1.Length);
CollectionAssert.AreEqual(plain, plain1);
insecure.Position = 0;
secure = new Psk1Stream(insecure, psk);
secure.ReadAsync(plain2, 0, plain2.Length).Wait();
CollectionAssert.AreEqual(plain, plain2);
}