ByteBuffer buffer = ByteBuffer.allocate(4 + 4 + 4 + bytes.length);
buffer.putInt(PROTOCOL_MAGIC);
buffer.putInt(header);
buffer.putInt(bytes.length);
buffer.put(bytes);
buffer.flip();
return buffer;
}
/**
* @return the last version associated with address, or @param version if this is the first such version