Asymmetric tunnels in P2MP LSPs as a label space reduction method

The objective of traffic engineering is to optimize network resource utilization. Although several works have been published about minimizing network resource utilization, few works have focused on LSR (label switched router) label space. This paper proposes an algorithm that takes advantage of the MPLS label stack features in order to reduce the number of labels used in LSPs. Some tunnelling methods and their MPLS implementation drawbacks are also discussed. The described algorithm sets up NHLFE (next hop label forwarding entry) tables in each LSR, creating asymmetric tunnels when possible. Experimental results show that the described algorithm achieves a great reduction factor in the label space. The presented works apply for both types of connections: P2MP (point-to-multipoint) and P2P (point-to-point)

A Label space reduction algorithm for P2MP LSPs using asymmetric tunnels

The aim of traffic engineering is to optimise network resource utilization. Although several works on minimizing network resource utilization have been published, few works have focused on LSR label space. This paper proposes an algorithm that uses MPLS label stack features in order to reduce the number of labels used in LSPs forwarding. Some tunnelling methods and their MPLS implementation drawbacks are also discussed. The algorithm described sets up the NHLFE tables in each LSR, creating asymmetric tunnels when possible. Experimental results show that the algorithm achieves a large reduction factor in the label space. The work presented here applies for both types of connections: P2MP and P2P

On optimal computation of MPLS label binding for multipoint-to-point connections

Most network operators have considered reducing Label Switched Routers (LSR) label spaces (i.e. the number of labels that can be used) as a means of simplifying management of underlaying Virtual Private Networks (VPNs) and, hence, reducing operational expenditure (OPEX). This letter discusses the problem of reducing the label spaces in Multiprotocol Label Switched (MPLS) networks using label merging - better known as MultiPoint-to-Point (MP2P) connections. Because of its origins in IP, MP2P connections have been considered to have tree- shapes with Label Switched Paths (LSP) as branches. Due to this fact, previous works by many authors affirm that the problem of minimizing the label space using MP2P in MPLS - the Merging Problem - cannot be solved optimally with a polynomial algorithm (NP-complete), since it involves a hard- decision problem. However, in this letter, the Merging Problem is analyzed, from the perspective of MPLS, and it is deduced that tree-shapes in MP2P connections are irrelevant. By overriding this tree-shape consideration, it is possible to perform label merging in polynomial time. Based on how MPLS signaling works, this letter proposes an algorithm to compute the minimum number of labels using label merging: the Full Label Merging algorithm. As conclusion, we reclassify the Merging Problem as Polynomial-solvable, instead of NP-complete. In addition, simulation experiments confirm that without the tree-branch selection problem, more labels can be reduced

Full label space reduction in MPLS networks: asymmetric merged tunneling

Traffic Engineering objective is to optimize network resource utilization. Although several works have been published about minimizing network resource utilization in MPLS networks, few of them have been focused in LSR label space reduction. This letter studies Asymmetric Merged Tunneling (AMT) as a new method for reducing the label space in MPLS network. The proposed method may be regarded as a combination of label merging (proposed in the MPLS architecture) and asymmetric tunneling (proposed recently in our previous works). Finally, simulation results are performed by comparing AMT with both ancestors. They show a great improvement in the label space reduction factor

Label Space Reduction in MPLS Networks: How Much Can A Single Stacked Label Do?

Most network operators have considered reducing LSR label spaces (number of labels used) as a way of simplifying management of underlaying virtual private networks (VPNs) and therefore reducing operational expenditure (OPEX). The IETF outlined the label merging feature in MPLS-allowing the configuration of multipoint-to-point connections (MP2P)-as a means of reducing label space in LSRs. We found two main drawbacks in this label space reduction a)it should be separately applied to a set of LSPs with the same egress LSR-which decreases the options for better reductions, and b)LSRs close to the edge of the network experience a greater label space reduction than those close to the core. The later implies that MP2P connections reduce the number of labels asymmetrically

All-Optical Label Stacking: Easing the Trade-offs Between Routing and Architecture Cost in All-Optical Packet Switching

All-optical label swapping (AOLS) forms a key technology towards the implementation of all-optical packet switching nodes (AOPS) for the future optical Internet. The capital expenditures of the deployment of AOLS increases with the size of the label spaces (i.e. the number of used labels), since a special optical device is needed for each recognized label on every node. Label space sizes are affected by the way in which demands are routed. For instance, while shortest-path routing leads to the usage of fewer labels but high link utilization, minimum interference routing leads to the opposite. This paper studies all-optical label stacking (AOLStack), which is an extension of the AOLS architecture. AOLStack aims at reducing label spaces while easing the compromise with link utilization. In this paper, an integer lineal program is proposed with the objective of analyzing the softening of the aforementioned trade-off due to AOLStack. Furthermore, a heuristic aiming at finding good solutions in polynomial-time is proposed as well. Simulation results show that AOLStack either a) reduces the label spaces with a low increase in the link utilization or, similarly, b) uses better the residual bandwidth to decrease the number of labels even more

Lightweight monitoring of label switched paths for bandwidth management

The purpose of resource management is the efficient and effective use of network resources, for instance bandwidth. In this article, a connection oriented network scenario is considered, where a certain amount of bandwidth is reserved for each label switch path (LSP), which is a logical path, in a MPLS or GMPLS environment. Assuming there is also some kind of admission control (explicit or implicit), these environments typically provide quality of service (QoS) guarantees. It could happen that some LSPs become busy, thus rejecting connections, while other LSPs may be under-utilised. We propose a distributed lightweight monitoring technique, based on threshold values, the objective of which is to detect congestion when it occurs in an LSP and activate the corresponding alarm which will trigger a dynamic bandwidth reallocation mechanism

Basic laser printing WSA (Mac)

Video on how to print to a Ricoh laser printer at WSA from a Mac, applies University wide just don't print WSA Colour or WSA Black & White if you are not WSA based.

Digital Printing and PDF creation

Short videos and Guides on how to print to various devices at WSA. Why 300dpi is important for printing, why PDF's are the defacto standard for printing and the how and where to get your files printed.

Printing PowerPoint Posters

This is a step-by-step guide for students who wish to print low-cost posters created using PowerPoint on large-format printers maintained by iSolutions.

Digital Printing

A collection of materials on digital printing geared for WSA. PDF being the defacto standard to print from.

Printing only part of an MS Word 2010 document

You won't always want to print the whole of your document; here are some useful ways of printing only part of a MS Word 2010 file. For best viewing Download the video.

Mac Printing Password update (workaround)

Quick video for iSolutions to sanity check workaround as all staff will be asked to change network passwords which could have a major affecting on staff authenticating to network printers from a Mac. If good can be used by Serviceline. Do not Contact Adam Procter about this

Textiles - Screen Printing Training

Training on techniques needed to use the textile screen printing facilities at WSA. Please note that watching these videos does not mean you are authorised to use these machines, this is for reference after a formal in person induction.

Evaluación de la gestión de residuos derivados del proceso de impresión en Datapoint de Colombia S.A.S, y propuesta de mejora

Este trabajo se centra en el análisis de las actividades desarrolladas en torno a los servicios de procesos de impresión que ofrece la organización DATAPOINT de Colombia SAS para identificar los puntos críticos en la gestión de los residuos de impresión y las decisiones tomadas por parte de los involucrados durante todo el proceso (proveedores, clientes y la empresa), con el fin de revisar medidas y estrategias que permitan fortalecer la gestión integral de residuos de impresión a partir de una revisión y comparación de las mejores prácticas planteadas por los actores del sector. También se efectuaron recomendaciones con acciones de mejora que se podrían desarrollar con el fin de mitigar el impacto ambiental generado por estos residuos. Con la finalidad de cumplir con lo planteado se realizó inicialmente un estudio sobre la organización, sus clientes y proveedores para entender de manera integral la cadena de valor en torno a los tóner y su gestión inversa, (explicar) al igual que el entorno normativo tanto de manera nacional como internacional. Posteriormente, se identificaron los puntos de mejora comparando lo planteado por el proveedor versus lo ejecutado por los involucrados en el proceso, labor se realizó en campo con los clientes para entender la situación actual, sus necesidades y en que basan la toma de decisiones relacionada con el manejo de los residuos de impresión. Finalmente se listaran una serie de acciones de mejora y recomendaciones las cuales pueden ser incorporadas a los procesos críticos de DATAPOINT.