Question: Is the MAC address available in your devices globally registered? What is the significance of this?
Answer: MAC-addresses of Devices supplied by Tibbo are not globally registered. Let us first explain what all this registration business is all about.
MAC-address of every device on the Ethernet network must be unique. This is absolutely necessary for correct operation of Ethernet. Now, what matters here is that all Ethernet devices on the same network segment are unique. The network segment boundary is where the router is. If there are two different Ethernet devices with the same MAC-address on different network segments (i.e. there is a router between those two devices) then there is no problem. If such two unlucky devices are located on the same network segment then this will cause a problem.
In the beginning of the Ethernet era the idea for assigning MAC-addresses was to use purely random numbers. MAC-address consists of 6 bytes so it has astronomically large address range. The chance of two devices with exactly the same MAC-address “meeting” on the same little network segment is amazingly small.
In later years somebody somewhere obviously decided that such “random” system was not good enough. Or maybe this somebody just wanted to make some money. Anyhow, a special international body was created to allocate MAC-addresses in “orderly fashion”. Idea is simple. MAC-address is split into two parts (fields) one of which is a sort of “company ID”. The rest of the address is used by this particular company to generate never-repeating MAC-addresses.
Tibbo did not purchase its own range of MACs. Contrary to what you may think, the purpose was NOT to save money. It is just that our main business is in “module” devices like EM100 and such devices go into our customer's machines and our customers very often prefer to purchase and set their own MAC-addresses.
When Tibbo devices are manufactured they are preset with never-repeating (within Tibbo) MAC-addresses. Theoretically, there is a chance that once upon a time one of our addresses will coniside with the address somebody else is using already. In practice, the odds of this happening are extremely low. Remember, the addresses not only have to match for the problem to occur, but also those two Ethernet devices must meet on the same network segment! And what are the odds of this ever happening considering enormous 6-byte address range we are dealing with? Nil!
If you, as a manufacturer, are interested in purchasing your own range of MACs you can do this here (the price is reasonable).
