This section introduces aspects that may be helpful in facilitating a better understanding of the invention. Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is in the prior art or what is not in the prior art.
A mesh network is used for transporting mesh flows, i.e. flows of packets having a unique source and destination node, along fixed paths established between nodes of the network. A path established for such a mesh flow is realized by combining multiple subsequent single-hop transmissions between neighboring mesh nodes, the single-hop transmissions being implemented using wireless or wire-line links, in the following also being referred to as mesh links. Packet forwarding at the mesh relay nodes, i.e., mesh points, is realized based on local packet forwarding information, e.g., based on label-switching after performing a setup-process of mesh flows.
The major application areas of such carrier-class mesh networks are (1) extending radio access networks on a temporary basis for coverage or capacity, e.g., by adding small cells with in-band backhauling and (2) to run temporary communication systems for rescue operations in environments with a broken infrastructure, e.g., after an earth-quake, hurricane or tsunami catastrophes. Supporting a heterogeneous set of link technologies which are integrated into the same mesh network is a requirement in scenarios where different spatial environments have to be traversed with mesh links. Different wireless or wire-line link technologies are typically tailored to different environments as indoor/outdoor and, in the case of wireless link technologies, simple or difficult radio interference situations. Integrating heterogeneous link technologies into a single mesh network allows for providing better/cheaper mesh networks. Moreover, even if only a single link technology is used in a mesh network, that technology may be implemented using different link configurations/different versions of the same technological standard, such that also for mesh networks using a single link technology, a situation which is similar to a network using heterogeneous link technologies may arise.
As wireless (and wire-line) resources are scarce resources—especially since in mesh networks they are also used for backhauling traffic of other links/cells—resource management mechanisms have to be applied in order to avoid network congestions and in order to provide communication services based on agreed service levels. Thus, for providing predictable communication services in mesh networks, an appropriate capacity management system for wireless and/or wire-line resources has to be established.
Such a mesh capacity management system has to be adapted for performing admission control of new mesh flows and for mesh optimizations which re-arrange already established mesh flows inside the mesh network. Admission control decisions (whether to accept new mesh flows or not) are based on calculations of remaining link capacities and calculations of expected flow traffic performance measures. The mesh routing/admission control may do this for different potential paths and selects the best path, if such a path can be established without violating capacity bounds and service quality constraints, e.g., delay, and without interfering with other flows breaking their service level agreements. If these constraints are violated, a request for establishing a new mesh flow on the network will be rejected. When accepting a new mesh flow, the path is configured and possibly resource reservations at the link level are made.
Mesh network admission control and mesh network optimizations are based on the calculation of flow performance characteristics, such as resource consumptions and other flow performance measures, e.g. an expected per-hop delay, which may be used to derive/correspond to fitness values for new potential flow distributions inside the mesh. The fitness values are functions taking remaining link capacities and predicted mesh flow traffic performance parameters into account.
Both types of calculations performed by the capacity management system, i.e. the remaining link capacity calculations as well as predictions of mesh flow traffic performance measures are based on:                (1) fixed properties of mesh links and link groups such as maximum capacity or available physical resources,        (2) on current or hypothetical setups of mesh flows in the mesh, i.e., minimum bitrate, burstiness, and maximum delay, and        (3) on a calculation model how to derive remaining capacities at links and mesh flow traffic performance measures.        
Current capacity management systems are based on pre-defined calculation models (3) that are implemented in the capacity management system for calculating resource consumption from link properties (1) and mesh state information (2). Also, traffic characteristics and traffic types of mesh flows may be taken into account for this purpose. The pre-defined calculation models used in mesh capacity management systems know about the link properties and how to calculate remaining link capacities as well as how to calculate the resulting properties of single-hop and end-to-end mesh flow properties. For this purpose, methods known from science and engineering such as teletraffic theory may be applied in order to derive link capacity limits and end-to-end mesh flow transmission properties from mesh state information.
However, the calculation model which has to be applied in a mesh capacity management system has to be known beforehand, i.e. when engineering the mesh system, or even has to be standardized in order to allow an inter-working of mesh links/mesh capacity management of different vendors. Yet, especially for heterogeneous wireless mesh networks, it is difficult to find a one-fits-all calculation model of remaining link capacities and predictions of traffic performance measures. Furthermore, it is difficult to find a generic calculation model that is purely based on link parameters and state information.
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