RAC concerns for longevity of the OUI / MAC Address registry Robert M.

RAC concerns for longevity of the OUI / MAC Address registry Robert M. Grow Chair, IEEE Registration Authority Committee

OUI registry OUI registry provides a 24 bit company identifier All assigned OUIs have two appropriate bits as zero to allow use in creation of universally (aka, globally) unique MAC addresses The RAC has “products” based on OUIs, that provide MAC addresses

OUI registry longevity Target was for 100 year longevity We are now 40 years into assignment of OUI identifiers (including Xerox assignments) Current rate of use if maintained is not a problem for exhaustion of values Rate of consumption though is not linear, it is accellerating, hence concern How many still want to be able to use 48-bit addresses 60 years from now?

Company ID (CID) OUIs are being consumed for identifiers where no MAC addresses are needed. Multiple 48-bit MAC addresses are now common on devices – Products consuming 128 addresses per network interface were an alarm CID can be used to reduce consumption of OUIs for non-address purposes as well as for reduction of consumption of MAC addresses

RAC considerations From earliest consideration of introducing a CID product, use of CID as a base for local addresses was always part of the debate This is evident from RAC tutorials