Performance Evaluation of Aggregate Flow Control on Differentiated Services Syatem

Abstract

Abstrak

Differentiated Services (Diffserv) menyediakan cara yang sederhana untuk menangani Quality of Service (Qos) di dalam jaringan Internet Protocol (IP) dengan mekanisme klasifikasi paket dan pembedaan perlakuan, serta alokasi sumber daya jaringan untuk trafik-trafik tertentu. Masalah yang sering terjadi di Diffserv adalah unfairness dan kongesti. Untuk mengatasi masalah tersebut, maka diperlukan suatu mekanisme yang dapat mengatur aliran paket data, salah satunya adalah Aggregate Flow Control (AFC). Penggunaan AFC pada sistem tidak hanya mengendalikan kongesti, tetapi juga meningkatkan fairness dalam throughput sehingga dalam penelitian ini, kinerja Diffserv tanpa dan dengan AFC, yaitu troughput dan packet loss dievaluasi menggunakan Network Simulator 2 (NS-2). Skenario simulasi yang digunakan dalam penelitian adalah simulasi variasi jumlah microflows, variasi ukuran paket, variasi RTT, dan variasi kelas AF. Hasil simulasi menunjukkan bahwa Diffserv dengan AFC dapat meningkatkan fairness dalam throughput dan menekan packet loss yang terjadi di dalam jaringan. Namun, untuk simulasi variasi kelas AF, Diffserv dengan AFC tidak dapat menciptakan fairness dalam throughput tetapi dapat menekan packet loss yang terjadi di dalam jaringan.

 

Kata kunci: aggregate flow control, differentiated service, fairness, network simulator, quality of service, AF PHB.

 

 

Abstract

 

Differentiated Services (Diffserv) provides a simple way for addressing Quality of Service (QoS) in the network Internet Protocol (IP) with the packet classification mechanism and treatment differentiation as well as network resources allocation for certain traffics. A problem frequently occurs in Diffserv is unfairness and congestion. To overcome these problems, a mechanism is required to regulate the flow of data packets, one of which is Aggregate Flow Control (AFC). The use of AFC in the system does not only control congestion but also improve the fairness in throughput. This study therefore evaluates the performance of Diffserv with and without AFC, namely  throughput and packet loss, using the Network Simulator 2 (NS-2). Simulation scenario used in this study were simulations of varied microflows amount, packet size, RTT, and AF class. Simulation result showed that Diffserv with AFC could increase fairness in throughput and decrease packet loss in network. In the case of AF class variation, Diffserv with AFC could not increase fairness in throughput but decrease the packet loss that happened in the network.

 

Keywords:     aggregate flow control, differentiated service, fairness, network simulator, quality of service, AF PHB.