Route Distinguisher txt Route Distinguisher, (x.x.x.x:yyy|xxxx:yyyy) ^((25[0-5]|2[0-4][0-9]|[1][0-9][0-9]|[1-9][0-9]|[0-9]?)(\.(25[0-5]|2[0-4][0-9]|[1][0-9][0-9]|[1-9][0-9]|[0-9]?)){3}|[0-9]{1,10}):[0-9]{1,5}$