Abstract:
Differentiated Servicc Network (DiffServ) provides
an architecturc that is scalable and capable of differentiating
applications' quality of service (QoS). However, if the flows
use packets of different sizes, resouce sharing is no longer
fair. Now for some applications, such as Internet telephony,
it is more natural to adjust the packet size. In this paper
we study the impact of variations in packet size on DiffServ
and propose methods to remove the throughput bias resulting
from the use of different packet sizes. The paper suggests a
solution that involes im Resource Discovery (RD) feedback
loop and Fair Intelligent Admission Control (FIAC) scheme
for each DiffServ domain (RD-FIAC-DiffServ). The scheme is
characterized by three fundamental features. First, the RD loop
introduces the virtual class-unit that is used to measure the
available resources rather than packet size. Second, the RD loop
infers the availability of network resources, yet for scalability,
it does not inovlves core routers. Lastly, the admission control
module understands incoming traffic's requirements, reconciles
with available resources via the RD loop, and admits traffic
intelligently according to the FIAC algorithm.
We evaluate these designs through simulation and conclude
with some concrete findings that RD-FIAC-DiffServ are robust
enough independent of packrt size and also can he used to
improve fairness among flows within the class.
