Network Abstraction Layer Software for Windows CE

General Description / Introduction

The CoSphere Network Abstraction Layer (NAL) software provides applications on Windows CE devices with information on available network resources and means to control these resources (limited for now). The latest version (1.1) consists of a number of parts: the 'nalsrv' service running as a background process on the device, the 'nallib' static library and the 'naldll' shared library that applications use to connect to nalsrv, and 'language bindings' for both C# and Java. The nalsrv interacts with the operating system and offers a cross-layer (link / network / transport) network resource abstraction to applications. This abstraction is expressed using the 'Network Resource Model' (NRM) and supports applications to select a view that best matches the application needs. The purpose of the NAL implementation is to investigate the adaptation of applications to dynamic network resources using this NRM. It basically offers hierarchies of types (inheritance) that describe entities at the link/physical, the network, and the transport layer and their interrelationships. By selecting a type in the hierarchy, the application sets the level of detail. The guiding principle here is that different kinds of applications need different levels of details to make decisions on the usage of network resources.

This work is part of the CoSphere PhD project.

Version 1.1 is used in the CoSphere Trial to collect mobility traces in heterogeneous network environments.

Publications: IEEE Internet Computing paper and COMSWARE'07 paper.

Screenshots

These two screenshots show nalsrv running on the device. The information in the bubble is by no means exhaustive (and focuses on the link layer). The console output is generated by nalsrv in debug mode.

Download

• Pocket PC 2003 SE - release [cab file] : copy to device or download with Pocket Explorer
• Pocket PC 2003 SE - debug [cab file] : copy to device or download with Pocket Explorer; will generate console output
• source code [zip file] : to be build with Visual Studio 2005

• Windows Mobile 5.0 Pocket PC - release [cab file] : copy to device or download with Pocket Explorer
• Windows Mobile 5.0 Pocket PC - debug [cab file] : copy to device or download with Pocket Explorer; will generate console output
• source code [zip file] : to be build with Visual Studio 2005

The sources are released under a GPL/LGPL license. Please, contact us to discuss other licensing possibilities.

Documentation

See the links at the top for the Network Resource Model schema documentation, the NRM schema in plain XML, and the online C sources for nalsrv, nallib, naldll, and languague bindings. See the CoSphere NRM - Application Usage slides.