   module ieee-types {

       // XXX namespace to be allocated by IANA

       namespace "urn:ietf:params:xml:ns:yang:ieee-types";
       prefix "ieee";

       import ietf-yang-types {
           prefix yang;
       }

       organization
           "YANG Language Design Team";

       contact
           "Juergen Schoenwaelder (Editor)
            <j.schoenwaelder@jacobs-university.de>";

       description
           "This module contains standard derived YANG types
            for IEEE 802 addresses and related things.";

       revision 2008-05-22 {
           description "Initial revision.";
       }

       /*
        * collection of IEEE address type definitions
        */

       typedef mac-address {
           type yang:phys-address {
               pattern '([0-9a-fA-F]{2}:){5}[0-9a-fA-F]{2}';
           }
           description
              "The mac-address type represents an 802 MAC address
               represented in the `canonical' order defined by
               IEEE 802.1a, i.e., as if it were transmitted least
               significant bit first, even though 802.5 (in contrast
               to other 802.x protocols) requires MAC addresses to
               be transmitted most significant bit first.";
           reference
              "RFC 2579 STD 58";
       }

       /*
        * collection of IEEE 802 related identifier types
        */

       typedef bridgeid {
           type string {
               pattern '[0-9a-fA-F]{4}:'
                     + '([0-9a-fA-F]{2}:){5}[0-9a-fA-F]{2}';
           }
           description
              "The bridgeid type represents identifers that uniquely
               identify a bridge.  Its first four hexadecimal digits
               contain a priority value followed by a colon. The
               remaining characters contain the MAC address used to
               refer to a bridge in a unique fashion (typically, the
               numerically smallest MAC address of all ports on the
               bridge).";
           reference
              "RFC 4188";
       }

       typedef vlanid {
           type uint16 {
               range "1..4094";
           }
           description
              "The vlanid type uniquely identifies a VLAN. This is
               the 12-bit VLAN-ID used in the VLAN Tag header. The
               range is defined by the referenced specification.";
           reference
              "IEEE Std 802.1Q 2003 Edition, Virtual Bridged Local
               Area Networks.";
       }
   }