GMPLS-controlled OBS Network Simulator: Implementation of the signaling protocol

Projecte final de carrera fet en col.laboració amb ISCTE-IUL LisboaThe Optical Burst Switching (OBS) paradigm is regaining greater attention by the professionals and researchers of the optical networking field, as it offers a number of advantages when compared with other optical switching paradigms. This type of technology was developed with the objective to carry information all-optically without using any kind of buffering device. However, due to its one-way signaling process, the presence of a control plane is extremely useful to manage complementary signaling and routing features, providing flexibility, reliability and taking more benefits of the OBS networks. The goal of this project is to extend Generalized Multiprotocol Label Switching (GMPLS) control plane architecture to properly handle OBS networks. In spite of GMPLS is not prepared to lead with these type of networks, this flexible architecture has been seen as a potential candidate to be used as the control plane of other kinds of optical networks (e.g., IP, Ethernet, Optical Circuit networks) and therefore to manage control OBS networks. In this project, the existent event-driven JAVA simulator for OBS networks – JAVOBS – is extended to simulate a possible interoperability model between GMPLS and OBS technologies. The first objective is to implement a new control layer (GMPLS) separated from the data layer of the OBS network. The second and main objective fits on the basic signaling procedures implementation of the GMPLS Reservation Protocol-Traffic Engineering (RSVP-TE) protocol, in order to analyze the performance of the OBS network’s behavior when it is controlled by such interoperable control plane (GMPLS/OBS)

Label Preference Schemes in GMPLS Controlled Networks

The GMPLS assumption that all available labels are equal is reasonable in electronic networks but not always true in WDM optical networks where labels correspond to physical wavelengths. In this paper we present two schemes for collecting the preference for specific labels during GMPLS signaling. For this purpose a new use of the Suggested Label object is proposed, and a novel object called Suggested Vector is introduced. The approach is validated through simulations showing significant wavelength converter usage reduction in aWDM optical network

Architecture, design, and modeling of the OPSnet asynchronous optical packet switching node

An all-optical packet-switched network supporting multiple services represents a long-term goal for network operators and service providers alike. The EPSRC-funded OPSnet project partnership addresses this issue from device through to network architecture perspectives with the key objective of the design, development, and demonstration of a fully operational asynchronous optical packet switch (OPS) suitable for 100 Gb/s dense-wavelength-division multiplexing (DWDM) operation. The OPS is built around a novel buffer and control architecture that has been shown to be highly flexible and to offer the promise of fair and consistent packet delivery at high load conditions with full support for quality of service (QoS) based on differentiated services over generalized multiprotocol label switching

A Survey on the Path Computation Element (PCE) Architecture

Quality of Service-enabled applications and services rely on Traffic Engineering-based (TE) Label Switched Paths (LSP) established in core networks and controlled by the GMPLS control plane. Path computation process is crucial to achieve the desired TE objective. Its actual effectiveness depends on a number of factors. Mechanisms utilized to update topology and TE information, as well as the latency between path computation and resource reservation, which is typically distributed, may affect path computation efficiency. Moreover, TE visibility is limited in many network scenarios, such as multi-layer, multi-domain and multi-carrier networks, and it may negatively impact resource utilization. The Internet Engineering Task Force (IETF) has promoted the Path Computation Element (PCE) architecture, proposing a dedicated network entity devoted to path computation process. The PCE represents a flexible instrument to overcome visibility and distributed provisioning inefficiencies. Communications between path computation clients (PCC) and PCEs, realized through the PCE Protocol (PCEP), also enable inter-PCE communications offering an attractive way to perform TE-based path computation among cooperating PCEs in multi-layer/domain scenarios, while preserving scalability and confidentiality. This survey presents the state-of-the-art on the PCE architecture for GMPLS-controlled networks carried out by research and standardization community. In this work, packet (i.e., MPLS-TE and MPLS-TP) and wavelength/spectrum (i.e., WSON and SSON) switching capabilities are the considered technological platforms, in which the PCE is shown to achieve a number of evident benefits

Multi-partner Demonstration of BGPLS enabled multi-domain EON control and instantiation with H-PCE

The control of multidomain elastic optical networks (EONs) is possible by combining Hierarchical Path Computation Element (H-PCE)-based computation, Border Gateway Protocol with Extensions for Traffic Engineering Link State Information (BGP-LS) topology discovery, remote instantiation via Path Computation Element Communication Protocol (PCEP), and signaling via Resource Reservation Protocol with Extensions for Traffic Engineering (RSVP-TE). Two evolutionary architectures are considered, one based on stateless H-PCE, PCEP instantiation, and end-to-end RSVP-TE signaling (SL-E2E), and a second one based on stateful active H-PCE with per-domain instantiation and stitching. This paper presents the first multiplatform demonstration that fully validates both control architectures achieving multiprotocol interoperability. SL-E2E leads to slightly faster provisioning but needs to keep the state of the stitching of the end-to-end label-switched paths in the parent PCE

On capacity planning for the GMPLS network control plane

The final publication is available at Springer via http://dx.doi.org/10.1007/s11107-007-0107-9This paper presents capacity planning rules for the control plane of all-optical networks featuring GMPLS and RSVP-TE as a connection setup protocol. As per RSVP standard, a refresh message mechanism is incorporated to RSVP such that the state is periodically refreshed on a link per link basis. We provide analytical expressions for the bandwidth and buffer sizes to be provided such that no flows are torn down due to lack of refresh messages. Our findings show that small buffers (several KBytes) suffice to sustain the signaling load for as much as 400 RSVP flows per link, with the simplest RSVP refresh mechanism (neither using link bundling nor acknowledgments). On the other hand, we also find the packet drop probability per link for a given network topology for the case that the flow survival probability is larger than a given threshold. We provide numerical examples based on the COST 239 european network topology and real RSVP traffic traces from early-commercial switching equipment.This work was funded by EU Project NOBEL (FP6-506760), Project CELTIC-FIRM and the Spanish MEC (project CAPITAL subproject code: TEC2004- 05622-C04-04 and project PINTA