This article gives an insight on the importance to assign a different capacity to each network link and to tighten the Quality of Service (QoS) provision in the network, in dynamic WDM Optical Networks with wavelength continuity constraints. In the text, several examples illustrate the performance of different strategies. The usual procedure to compute the number of wavelengths of each network link consists of choosing the same capacity to each link on the network. This decision is selected, in most cases, by simplicity and simulation limitations. Notwithstanding, there are no technical motives to force a uniform capacity on the network. In consequence, we analyze the impact on the network capacity of designating the minimum amount of wavelengths to each network link, while satisfying each user QoS requirement. Moreover, despite the chosen dimensioning strategy, it is usual to offer a much better QoS than requested for some users, with the corresponding waste of resources. We can amend this issue by limiting which wavelengths are available to each user according to its particular QoS constraint. This technique, known as Wavelength Grouping, seeks to provide to each user a QoS level closer to the one defined in the Service Level Agreement. By doing so, it is possible to reduce the network capacity needed to allow communication to its user, or diminishing the network blocking probability for a given wavelength capacity. In spite of the usual approach, in this work, we demonstrate that a non-uniform dimensioning strategy and a tighten QoS provision allows to save significant networks capacity, while simultaneously provisioning to each user the QoS established in its Service Level Agreement. This fact is very relevant nowadays, where an impending capacity crunch in optical networks is an important issue.

本文提供了在具有波长连续性约束的动态WDM光网络中，为每个网络链路分配不同容量并加强网络中服务质量（QoS）的重要性的见解。在本文中，有几个示例说明了不同策略的性能。计算每个网络链路的波长数的通常过程包括为网络上的每个链路选择相同的容量。在大多数情况下，此决定是由简单性和模拟限制决定的。尽管如此，没有任何技术动机来强制网络上具有统一的容量。因此，我们分析了在满足每个用户QoS要求的同时，为每个网络链路指定最小波长量对网络容量的影响。此外，尽管选择了确定尺寸的策略，但通常会提供比某些用户要求的服务质量更好的QoS，同时会浪费资源。我们可以通过限制每个用户根据其特定QoS约束可用的波长来修正此问题。这项称为波长分组的技术旨在为每个用户提供更接近服务等级协议中定义的QoS等级。通过这样做，可以减少允许与其用户进行通信所需的网络容量，或者减小给定波长容量的网络阻塞概率。尽管采用了通常的方法，但在这项工作中，我们证明了不统一的尺寸调整策略和严格的QoS规定可以节省大量的网络容量，同时向每个用户提供其服务级别协议中建立的QoS。如今，这一事实非常重要，光网络中即将出现的容量紧缩是一个重要问题。