A method is provided for performing a map update for a navigation device. The method includes: receiving a manifest file corresponding to a map update package and receiving a digital signature corresponding to the manifest file, wherein the map update package comprises a plurality of pieces; verifying, by a processor, the digital signature; receiving, after successful verification of the digital signature, a piece of the map update package to be written to a storage of the navigation device; verifying, by the processor, the received piece using the received manifest file; and writing, in response to successful verification of the received piece, the received piece to the storage of the navigation device.