The DS2401 and DS2411 devices are 64-bit read only memory (ROM) "silicon serial number" devices from Dallas Semiconductor/Maxim. The devices are programmed by the manufacturer with a unique 48 bit serial number, an 8 bit product family code, and an 8 bit CRC. The family code is the same at 01h for both DS2401 and DS2411 devices. The stored data can be read from the devices through the Dallas 1-Wire protocol.
The TinyOS code related to DS2401 can be found here.
Technical details and datasheets for these devices can be found at
The DS2401 and DS2411 ICs are used in the following devices