Browse Prior Art Database

Content Segment Descriptor for Improved Segmented Software Download

IP.com Disclosure Number: IPCOM000019651D
Published in the IP.com Journal: Volume 3 Issue 10 (2003-10-25)
Included in the Prior Art Database: 2003-Oct-25
Document File: 4 page(s) / 215K

Publishing Venue

Siemens

Related People

Juergen Carstens: CONTACT

Abstract

In mobile systems, efficient download of content to mobile devices plays an important role. Such content can be e.g. multi-media data, as music or videos, applications, and software updates for re-configurable mobile radio terminals. Future mobile radio terminals will support different radio interfaces, which will possibly be used simultaneously. For a flexible and efficient download over different radio interfaces, it has been proposed to segment the download. This means that the whole content to be downloaded is split into segments (also called packets). The segments can be loaded from different radio channels, and the receiving radio terminal collects all the segments and recombines them to form the complete content. Different segments can also be loaded simultaneously, and they don't have to be loaded in a specific order. It has been shown that splitting the content download into several sessions transmitted over different air interfaces with support of simultaneous connections for individual terminals will highly enhance the spectrum efficiency in terms of trunking gain. This download scheme is underlying the here proposed encrypting method.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 33% of the total text.

Page 1 of 4

S

© SIEMENS AG 2003 file: 2003J12593.doc page: 1

Content Segment Descriptor for Improved Segmented Software Download

Idea: Dr. Rainer Falk, DE-Munich; Jijun Luo, DE-Munich; Markus Dillinger, DE-Munich

In mobile systems, efficient download of content to mobile devices plays an important role. Such content can be e.g. multi-media data, as music or videos, applications, and software updates for re- configurable mobile radio terminals. Future mobile radio terminals will support different radio interfaces, which will possibly be used simultaneously.

For a flexible and efficient download over different radio interfaces, it has been proposed to segment the download. This means that the whole content to be downloaded is split into segments (also called packets). The segments can be loaded from different radio channels, and the receiving radio terminal collects all the segments and recombines them to form the complete content. Different segments can also be loaded simultaneously, and they don't have to be loaded in a specific order. It has been shown that splitting the content download into several sessions transmitted over different air interfaces with support of simultaneous connections for individual terminals will highly enhance the spectrum efficiency in terms of trunking gain. This download scheme is underlying the here proposed encrypting method.

For certain types of content it is important that the terminal can verify the integrity as well as the source of the content. In the case of a segmented download, the integrity of each segment has to be valid, and all valid segments have to be combined correctly to form a valid overall content. Although the integrity of each segment is valid, the combined content might be not. The segments can be equipped with logically attached session numbers (primary identification of content) and packet indexing (position of the segment belonging to the committed content), but this is still not sufficient to guarantee a reliable software download (SD), since the numbering scheme can easily be manipulated.

To verify the integrity and the source of the received content, a cryptographic checksum of the content can be used, which is either a digital signature using public-key cryptography (signed content) or a message authentication code (MAC) using secret-key cryptography. The receiving terminal then verifies the sum. For the segmented download, this method can either be applied to the whole content, the individual segments, or both. Accordingly, the terminal verifies the integrity of each received segment and/or the integrity of the complete content. If the cryptographic checksum is applied to the whole content, there is the problem that in case of an unsuccessful verification, the receiver doesn't know which segment has been corrupted (Fig. 1). If the checksum is applied to every single segment, every segment has to contain an identifier, that determines to which context it belongs and which part of the...