Abstract
The extended network span of next-generation long-reach passive optical
networks (LR-PONs) results in extremely long propagation delays that severely
degrade the performance of centralized bandwidth allocation algorithms. This
is because these algorithms are based on bandwidth negotiation messages frequently
exchanged between the optical line terminal (OLT) in the central office and
optical network units (ONUs) near the users, which become seriously delayed
when the network is extended. To address this problem, we propose a decentralized
media access scheme for emerging LR-PONs to make the performance independent
of the physical length between the OLT and ONUs. We also maintain centralized
control over the network, usually missed in conventional decentralized schemes,
to support and manage quality of service according to user service level agreements.
The scheme thus combines decentralized media access with centralized control
to meet the special requirements of emerging LR-PONs. We investigate the performance
of the proposed scheme in contrast with centralized schemes under worst case
conditions. We also explore various approaches to further enhance the performance
of our scheme. Simulation results show that the average upstream packet delay
can be decreased by 60% while also maintaining a high throughput.
© 2011 IEEE
PDF Article
More Like This
Cited By
You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
Contact your librarian or system administrator
or
Login to access Optica Member Subscription