Created attachment 1791 [details]
Patch to remove AsInt

static uint8_t
AsInt (std::string v)
{
  NS_LOG_FUNCTION (v);
  std::istringstream iss;
  iss.str (v);
  uint32_t retval;
  iss >> std::hex >> retval >> std::dec;
  return retval;
}

is functionally equivalent to:
strtoul (tmp.c_str(), 0, 16)

The difference is the speed. AsInt is 20x time *slower*. See:
http://tinodidriksen.com/2010/02/16/cpp-convert-string-to-int-speed/

We're lucky that the stream extraction operator (where AsInt is called) isn't used often...