Generalized multiprotocol label switching, also referred to as multiprotocol lambda switching, supports not only devices that perform packet switching, but also those that perform switching in the time, wavelength, and space domains. The development of GMPLS requires modifications to current signaling and routing protocols. It has also triggered the development of new protocols such as the Link Management protocol. We present the traffic engineering enhancements to the Open Shortest Path First Internet routing protocol and ISIS Intradomain Routing Protocol, two popular routing protocols, to support GMPLS. We present the concepts of generalized interfaces, label-switched path hierarchy, and link bundling intended to improve GMPLS scalability. We also discuss the Link Management Protocol which can be used to make the underlying links more manageable.

Generalized multiprotocol label switching: an overview of routing and management enhancements

With high-bandwidth and on-demand applications continuing to emerge, next-generation core optical networks will require significant improvements in capacity, configurability, and resiliency. These advancements need to be achieved with architectures and technologies that are scalable with respect to network cost, size, and power requirements. To investigate the limitations of extending today's solutions to meet these goals, a North American backbone network with a tenfold growth in traffic is modeled. The results of this paper illuminate at least three areas that will potentially require innovative solutions, namely 1) transmission modulation formats, 2) switching granularity, and 3) edge traffic grooming. In addition to probing issues related to increased capacity, configurability is also examined, mainly in the context of switching architectures. Advanced network protection is discussed as well, at a high level. A central theme is how to harness the trend of optics scaling better than electronics. Throughout this paper, potential advancements in architecture and technology are enumerated to serve as a foundation for the research needed to attain the goals of next-generation core networks

Evolution toward the next-generation core optical network

Dynamic resource allocation in GMPLS optical networks (DRAGON) defines a research and experimental framework for high-performance networks required by grid computing and e-science applications. The DRAGON project is developing technology and deploying network infrastructure which allows dynamic provisioning of network resources in order to establish deterministic paths in direct response to end-user requests. This includes multidomain provisioning of traffic-engineering paths using a distributed control plane across heterogeneous network technologies while including mechanisms for authentication, authorization, accounting (AAA), and scheduling. A reference implementation of this framework has been instantiated in the Washington, DC area and is being utilized to conduct research and development into the deployment of optical networks technologies toward the satisfaction of very-high-performance science application requirements.

DRAGON: a framework for service provisioning in heterogeneous grid networks

With the continuing growth in the amount of backbone traffic, improving the cost-effectiveness and ensuring survivability of the underlying optical networks are very important problems facing network service providers today. In this paper, we propose a bandwidth squeezed restoration (BSR) scheme in our recently proposed spectrum-sliced elastic optical path network (SLICE). The proposed BSR takes advantage of elastic bandwidth variation in the optical paths of SLICE. It enables spectrally efficient and highly survivable network recovery for best-effort traffic as well as bandwidth guaranteed traffic, while satisfying the service level specifications required from the client layer networks. We discuss the necessary interworking architectures between the optical path layer and client layer in the BSR in SLICE. We also present a control framework that achieves flexible bandwidth assignment as well as BSR of optical paths in SLICE. Finally, we describe an implementation example of a control plane using generalized multi-protocol label switching (GMPLS).

Bandwidth Squeezed Restoration in Spectrum-Sliced Elastic Optical Path Networks (SLICE)

With the advent of service sensitive applications such as remote controlled experiments, time constrained massive data transfers, and video-conferencing, it has become apparent that there is a need for the setup of dynamically provisioned, quality of service enabled virtual circuits. The ESnet on-demand secure circuits and advance reservation system (OSCARS) is a prototype service enabling advance reservation of guaranteed bandwidth secure virtual circuits. OSCARS operates within the energy sciences network (ESnet), and has provisions for interoperation with other network domains. ESnet is a high-speed network serving thousands of Department of Energy scientists and collaborators worldwide. OSCARS utilizes the Web services model and standards to implement communication with the system and between domains, and for authentication, authorization, and auditing (AAA). The management and operation of end-to-end virtual circuits within the network is done at the layer 3 network level. Multi-protocol label switching (MPLS) and the resource reservation protocol (RSVP) are used to create the virtual circuits or label switched paths (LSP's). quality of service (QoS) is used to provide bandwidth guarantees. This paper describes our experience in implementing OSCARS, collaborations with other bandwidth-reservation projects (including interdomain testing) and future work to be done.

/pdf/intra-and-interdomain-circuit-provisioning-using-the-oscars-2enqyxlu85.pdf

Intra and Interdomain Circuit Provisioning Using the OSCARS Reservation System

Generalized Multiprotocol Label Switching (GMPLS) defines both routing
and signaling protocols for the creation of Label Switched Paths
(LSPs) in various switching technologies. These protocols can be used
to support a number of deployment scenarios. This memo addresses the
application of GMPLS to the overlay model. [STANDARDS-TRACK]

/pdf/generalized-multiprotocol-label-switching-gmpls-user-network-3q6uqrcvu5.pdf

Generalized Multiprotocol Label Switching (GMPLS) User-Network Interface (UNI): Resource ReserVation Protocol-Traffic Engineering (RSVP-TE) Support for the Overlay Model

A method is described that includes accessing a signaling message for a frame to be transmitted through an optical network along a path, deriving an identifier of the path using the signaling message, attaching the identifier to an overhead section of the frame, and transmitting the frame through the optical network on the path with the attached identifier. For another embodiment, an apparatus is described that includes a controller coupled to a control plane of an optical network to receive a signaling message on a control plane, the signaling message specifying a change in a connection for a specified optical network communications circuit, and to forward the signaling message on the control plane, and an interface to an optical switching matrix to change the connection for the specified circuit after forwarding the signaling message.

Connection identifiers and restoration in optical networks

Generalized MPLS Recovery Mechanisms

Control Channel Bootstrap for Link Management Protocol

This document specifies a new Generic Associated Channel (G-ACh) for
Residence Time Measurement (RTM) and describes how it can be used by
time synchronization protocols within an MPLS domain. Residence time
is the variable part of the propagation delay of timing and
synchronization messages; knowing this delay for each message allows
for a more accurate determination of the delay to be taken into
account when applying the value included in a Precision Time Protocol
event message.

John Drake

Papers

Generalized Multiprotocol Label Switching (GMPLS) User-Network Interface (UNI): Resource ReserVation Protocol-Traffic Engineering (RSVP-TE) Support for the Overlay Model

Connection identifiers and restoration in optical networks

Generalized MPLS Recovery Mechanisms

Control Channel Bootstrap for Link Management Protocol

Residence Time Measurement in MPLS Networks