Active Resource Management (ARM) For The Differentiated Services Environment



Ananthanarayanan Ramanathan


The objective of this project is to provide for Quality of Service (QoS) in a network architecture. We are looking into the Differentiated Services architecture, which provides QoS to real time data. The Bandwidth Broker implementation provides a better bandwidth and resource reservation scheme in the Differentiated Services architecture. We are working at modifying the network architecture to provide active QoS management with the help of active networks and Bandwidth Brokers.


Most of the data that travels through the Internet today is either multimedia or real time data that's critical to some application. Such data require a certain level of guarantee that IP does not provide. Quality of Service (QoS) can be defined as: the network capability to provide a nondefault service to a subset of the aggregate traffic (As quoted by C. Metz. "IP QoS: travelling in the first class on the Internet." IEEE Internet Computing, Vol. 3, No. 2, March/April 1999). QoS refers to the classification of packets for the purpose of treating classes or flows of packets in a particular way as compared to other packets. In this project, we investigate the various networks that provide QoS. After studying the different networks, we decided that the Differentiated Services (DS) architecture is very effective in its method of providing QoS. In DS, all traffic flows are aggregated based on their Per Hop Behavior (PHB). PHB can be defined as externally observable forwarding behavior. It is used to define classes of service for the various packets. The DS routers are configured with these PHBs and based on them the forwarding of packets is done. Service Level Agreements (SLA) are decided for each flow, and correspondingly bandwidth is allocate. This allocation of bandwidth and other resources can be done better, if done by a centralized agent. This where the Bandwidth Broker fits. It is built like client server architecture. It stores the SLAs required for the various flows in a database and configures the edge routers of the DS network to forward the packets accordingly. The bandwidth broker can also be built to interact with the Brokers of the other DS domains and allocate resources according to their needs. Our work is to build a working implementation of the Bandwidth Broker and use active networks to allow dynamic allocation of resources. We will be running all these experiments on our testbed, which will expand as more requirements are visualized.


NS-2 (Network Simulator)

The code for ARM algorithm written for the network simulator (NS-2) is available. code


Manish Mahajan, Ananth Ramanathan and Manish Parashar, "Active Resource Management For The Differentiated Services Environment", submitted to International Journal of Network Management [Introduction].

Ananth Ramanathan and Manish Parashar, "Active Resource Management (ARM) For The Differentiated Services Environment", Internet Computing - 2001 conference.
(Abstract )   [(Presentation (Can be viewed only in IE)]

Current Status:

We used the NS-2 software to evaluate our algorithm.

Evaluation and Results:

We have evaluated the ARM algorithm using the NS-2 toolkit, and have managed to improve the bandwidth reservation in a differentiated services network.
[RESULTS  (Can be viewed only in IE)]

Future Work:

Plan to extend the bandwidth broker to manage application oriented resoource management and extend it beyond Differentiated Services to any generic network architecture.

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