code: private void setIP(final int startIndex, final String address) {
          final String[] parts = address.split("\\.");
          this.headers.setByte(startIndex + 0, (byte) Integer.parseInt(parts[0]));
          this.headers.setByte(startIndex + 1, (byte) Integer.parseInt(parts[1]));
          this.headers.setByte(startIndex + 2, (byte) Integer.parseInt(parts[2]));
          this.headers.setByte(startIndex + 3, (byte) Integer.parseInt(parts[3]));
          reCalculateChecksum();
      }
docs: Very naive initial implementation. Should be changed to do a better job
  and its performance probably can go up a lot as well.
  
  @param startIndex
  @param address