Saurav Das

Simple unified control for packet and circuit networks

OpenFlow is proposed as an architectural platform and a unified control plane for packet and circuit networks, with the main goal of simplifying network control and management while fostering innovative change in them.

Unifying Packet and Circuit Switched Networks

There have been many attempts to unify the control and management of circuit and packet switched networks, but none have taken hold. In this paper we propose a simple way to unify both types of network using OpenFlow. The basic idea is that a simple flow abstraction fits well with both types of network, provides a common paradigm for control, and makes it easy to insert new functionality into the network. OpenFlow provides a common API to the underlying hardware, and allows all of the routing, control and management to be defined in software outside the datapath.

MPLS with a simple OPEN control plane

We propose a new approach to MPLS that uses the standard MPLS data plane and an OpenFlow based simpler and extensible control plane. We demonstrate this approach using a prototype system for MPLS Traffic Engineering.

Rethinking IP core networks

The Internet core today is completely based on IP routers. Circuits are only used to provide static point-to-point optical links between routers. As others have recognized, current practice makes it hard to take advantage of very high-speed, low-power optical circuit switches in the core. Despite many proposals to mix packet switching with dynamic circuit switching, none have taken hold. In these times of rapidly increasing traffic, and rapidly decreasing profits for ISPs, it is time to rethink how backbones are built. In this paper, we propose to replace the largest backbone routers with much cheaper hybrid packet-optical switches in a fully meshed IP core. We take advantage of new control planes for software-defined networks to control the packet and circuit networks from a single vantage point. To demonstrate the enormous potential cost savings, we present a detailed analysis of the capital expenditure and show how our approach offers 60% cost savings for typical backbone operators.

Optical Burst Transport: A Technology for the WDM Metro Ring Networks

We propose a sublambda traffic-grooming scheme on wavelength-division-multiplexing ring networks, named optical burst transport. The network protocol and architecture are designed to support dynamic bandwidth allocation, which is more reasonable for bursty data traffic. To verify our network protocol and architecture, we build a testbed which supports burst-mode transmission. Also, we transmit streaming video over Ethernet as an application

Photonic components for future fiber access networks

Fiber based access networks are recognized as promising technologies for solving broadband bandwidth bottlenecks. TDM-PONs, which are passive and non-reconfigurable, are the most widely deployed type of fiber access networks today. However, due to their passive nature, TDM-PONs encounter several issues such as inflexible coverage, lack of intelligence for control, and inability to counter security attacks. Based on current issues in optical access networks, we propose a novel non-volatile, reconfiguration node. The proposed remote node can reconfigure the network to adapt to varying degrees of deployment conditions and/or network attacks. Moreover, the proposed remote node incorporates a novel quasi-passive device that reconfigures using remotely supplied energy from CO. This quasi-passive device technology does not consume any energy once it reconfigures into a new latching states. Therefore, the proposed remote node has very low energy consumption and does not require local power supply to preserve the passivity of the passive distribution network. In particular, the proposed quasi-passive device technology is implemented using a novel tri-state Micro- Electro-Mechanical System (MEMS) actuator structure and the device demonstrates very small energy consumption requirement to enable energy be remotely supplied from CO. Also, the MEMS structure is shown to demonstrate acceptable insertion losses to makes it suitable for flexible energy distribution. Simulation study shows the proposed reconfigurable device would outperform traditional passive splitter in terms of maximum number of supportable users under realistic deployment conditions.

OPN01-6: Enabling Security Countermeasure and Service Restoration in Passive Optical Networks

In this paper, we introduce a novel passive and wavelength selective remote node specifically designed to enable security countermeasure in PONs. The central office could physically isolate problem makers from the network without disrupting regular links by issuing a wavelength specific control signal to this device. With its wavelength selective nature, the countermeasure-enabled passive device is also a natural candidate to a WDM-PON remote node. To demonstrate its feasibility, a discrete version of the device is implemented. In addition to enable countermeasure capability, a new kind of PON restoration technique that employs a hybrid optical-wireless network is proposed. Finally, cost and performance considerations are discussed in an 8-channel planer lightwave circuit example.

Protection and Spatial Reuse in Optical Burst Transport (OBT) Networks

Optical Burst Transport network is a novel WDM ring architecture for Metropolitan Area Networks (MAN). It leverages the advantages of optical burst switching and WDM rings, while using a token-based medium access scheme. In this paper, we investigate protection together with spatial reuse property. Specifically we show how protection in OBT can be different from conventional protection and propose three algorithms for implementing a fast and low implementation cost, unidirectional 1:1 protection scheme. We analyzed the performance of these schemes via simulation and found an optimum algorithm for minimizing data loss and maximizing data delivery during the fault.

A Novel Technique for Denial of Service Identification in Optical Access Networks

We discuss the limitations of current optical access networks in providing protection against physical layer attacks like denial of service and present a scheme for identifying intruders causing this attack.

QoS Differentiation in OBT Ring Networks with Comparison to RPR Networks

Optical burst transport networks employ burst transmission in WDM ring architectures and are promising candidates for MANs. We investigate QoS differentiation in OBT, and compare its performance to IEEE 802.17 resilient packet ring (RPR) standard.