Qualnet is a parallel simulation platform for complex systems which was developed at UCLA to provide researchers with more efficient and convenient ways to simulate various testbeds that cannot be easily structured in real environment such as huge wired and/or wireless networks with a number of nodes. The Qualnet platform not only supports discrete-time message passing functionality for handling events occurring over various time scales, but also allows to take advantage of the power of parallel architectures with multiple processors for fast and scalable simulations. Qualnet was designed at UCLA with the goal of simulating networks that scale up to many thousands of nodes linked by a heterogeneous communications capability that includes multicasting, asymmetric communication links, direct satellite broadcast, multi-hop wireless ad hoc networking, and traditional, wired Internet connectivity. Qualnet uses a layered approach to develop high-fidelity models of the protocol stack to support multi-hop wireless communication in a mobile network. In Qualnet, the scaling to large networks is achieved primarily by exploiting parallel execution of the models. Prior to Qualnet, parallel simulation of wireless networks had been applied primarily to cellular type personal communication networks. In our proposed project, the Qualnet simulation platform will play an important role in guiding and validating our experiments.
In parallel with Qualnet, we will develop our code also on the NS2 simulator that is currently the leading open source network simulator. That strategy will allow us to share our results with a larger number of scientists as well as with the research groups operating within ST-Microelectronics.
The ad hoc
wireless testbed at UCLA consists of about twenty laptops and
60 PDAs equipped with IEEE 802.11 cards and running the Linux
operating system. This tesbed was assembled with funds from
DARPA, ONR and more recently HP. Several ad hoc networking
protocols have been implemented and tested on this testbed
including routing protocols (DSDV, Bellman Ford, ODMRP
unicast); multicast protocols (ODMRP multicast, DVMRP), IP
protocols (Ipv, Mobile IP), network management protocols
(SNMP) and transport protocols (TCP Reno and TCP
Westwood).
In addition, the ad hoc testbed is equipped
with video and audio traffic generators, video and speech
encoders, speech-to-text translators and speech
synthesizers. The ad hoc testbed has been used to carry out
several noteworthy experiments, including: video adaptation in
a varying network topology and channnel capacity environment,
and; multihop TCP experiments, exhibiting capture in the
presence of conflicting TCP sessions. More recently, the
testbed has been used to carry out audio and video vonference
experiments in support of a Campus wireless classroom project
sponsored by HP.
A Bluetooth lab is also
available. STMicroelectronics provided us 3 Bluetooth mini
kits; moreover we have acquired several Bluetooth cards and
are now engaged in Bluetooth propagation experiments. We have
also installed sensors on our small Bluetooth platforms and
are planning to develop a Bluetooth sensor "fabric"
(implemented by a scatternet) that allows a passing user to
retrieve the sensor data that he/she is interested in.
On a broader scale, the wireless Network Research Testebed (NRT) will make available Campus wide resources which will be extremely valuable for experimental validation of our results. The NRT resources will include: