Communication networks have evolved from circuit-switched and hop-by-hop routed systems into converged data/optical networks using the Internet as a common backbone carrying narrow- and broad-band traffic offered by a multitude of access networks. This data/optical backbone is built around a multi-technology/multi-protocol routing architecture where the IP protocols are running in a collapsed IP stack where ATM and SONET/SDH have been replaced by the suite of (Generalized) Multiprotocol Label Switching ((G)MPLS) suite of protocols. A further evolution referred to as "IP over Photons" or "All IP - All Optical" is expected where "redundant intermediate layers" will be eliminated to run IP directly on top of optical cross-connects (OXCs) with the expectation of achieving savings on operation expenditures (OPEX) and capital expenditures (CAPEX). This evolution has been stalled by the immaturity in the control and data plane technologies leading to complex and time-consuming manual network planning and configurations requiring a group of "layer experts".

By making the status of each link and node of a data/optical network visible to a common control including heterogeneous network elements which support different routing/switching capabilities, (G)MPLS protocols have opened the way for automated operation and management allowing the different layers of an IP stack to be managed by a single network operator. (G)MPLS protocols provide the potential to make more efficient use of the IP backbone by having network management techniques such as Traffic Engineering (TE) and Network Engineering (NE), once the preserve of telecommunications, to be reinvented and deployed to effect different Quality of Service (QoS) requirements in the emerging and next generation Internet. NE moves bandwidth to where the traffic is offered to the network while TE moves traffic to where the bandwidth is available to achieve QoS agreements between the current and expected traffic and the available resources.

However, several issues need to be resolved before TE and NE be effectively deployed in emerging and next generation IP networks. These include (1) the definition and localization of QoS routing mechanisms to be deployed at the different network layer interfaces of the emerging IP stack (2) the mapping of the application QoS requirements into QoS routing mechanisms and (3) the deployment of these mechanisms within and beyond an Internet domain's boundaries to maximize the engineering and economic efficiency.

Building upon different frameworks and research fields, this thesis revisits the issue of Traffic and Network Engineering (TE and NE) to present and evaluate the performance of different QoS routing mechanisms and network control strategies to be deployed at the different network layer interfaces of a hybrid data/optical network where an IP over MPLS network is layered above an MPLambdaS over fiber infrastructure. These include mechanisms and strategies to be deployed at the IP/MPLS, MPLS/MPLambdaS and MPLambdaS/fiber network layer interfaces. The main contributions of this thesis are threefold. First we propose and compare the performance of hybrid routing strategies to be deployed in IGP/MPLS networks by combining the connectionless routing model used by classical IGP protocols and the connection oriented routing model borrowed from MPLS. These strategies include IGP+MPLS models and control mechanisms where the paths followed by the traffic are selected by either classical constraint-based (CBR) routing is used to complement fine-tuned connectionless IGP routing or classical IGP routing is used in conjunction with improved fine-tuned CBR routing. Second, we propose QoS routing mechanisms and control strategies to be deployed at the MPLS/MPLambdaS network layer interface with a focus on layered routing using contention-aware routing mechanisms and multi-layer routing strategies combining faster Signalling and preemption to improve optimality and resilience. Finally, we build upon fiber transmission characteristics to propose Photonic aware routing mechanisms where the routing in the MPLambdaS layer is conducted by fiber availability and failure risk groups