fakelocWhat a MAC vendor lookup can and cannot tell you
Use registry prefixes as allocation clues and explain the uncertainty around local or randomized addresses.
The prefix points to registry allocation
A traditional 48-bit address lookup often examines the first three octets, known as an OUI-sized prefix. IEEE also maintains other assignment block sizes. The lookup dataset must match the prefix length it claims to support.
Allocation does not identify a product or person
A registry match may name an organization associated with an allocation. It does not reveal who currently owns a device, where it is located, or whether the prefix remains in active use.
Explain unmatched and local results plainly
No match can mean the data is absent, the address is locally assigned, the prefix uses a different allocation size, or the dataset is stale. Do not convert “unknown” into a guess.
Record source and update date
For operational use, show the registry source, dataset revision, and lookup date. fakeloc’s local lookup uses its published OUI data snapshot; it is a reference aid rather than a live IEEE query.