// longer valid
valid ? zk.generatePasswd(sessionId) : new byte[16]);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
BinaryOutputArchive bos = BinaryOutputArchive.getArchive(baos);
bos.writeInt(-1, "len");
rsp.serialize(bos, "connect");
baos.close();
ByteBuffer bb = ByteBuffer.wrap(baos.toByteArray());
bb.putInt(bb.remaining() - 4).rewind();
sendBuffer(bb);