byte C0 = 0x03;
out.write(C0);
long timestampC1 = System.currentTimeMillis();
byte[] randC1 = new byte[1528];
rand.nextBytes(randC1);
out.writeInt((int)timestampC1);
out.writeInt(0);
out.write(randC1, 0, 1528);
out.flush();
byte S0 = (byte)in.read();