Multiservice Switching Networks with Overflow Links and Resource Reservation

Abstract

This paper proposes a new analytical model of a multiservice switching network with overflow links in the first stage and resource reservation for selected call classes in output directions. The proposed model assumes that both the overflow mechanism and the resource reservation mechanism can be used in a number of selected, or all, classes of calls. A particular attention is given to the way the effective availability parameter for networks with overflow links in the point-to-point selection mode is determined. The proposed model makes it possible to determine dependencies between the internal blocking probability, capacity of overflow links, and the number of reserved resources for call classes to be analysed. Simulation experiments confirm high accuracy of the proposed method and potential applications of the model in engineering issues.

Overflows in Multiservice Systems

“…For the correspondence with the load intervals pre-defined earlier in (23), the assumption is that T i,0 = 0 and T i,q i +1 = V j . It should be noted that the parameter δ i,k = 1 only in this load area in which the allocated number of AUs to service a call is t i,k .…”

“…The assumption is that the LAG services streaming traffic and that it is composed of s identical component resources, each with the capacity f AUs. This group can model a group of, for example, s cells of a mobile network [48] or an output group of a switching network [22], [23]. The occupancy distribution in the j-th PR with distributed resources can be approximated by the distribution (11) dla v = V j = s j f j , while Function RF PRj (n) takes on the following form [81]: (27) where ξ i, j is the conditional transition probability for a stream of class i that can be determined combinatorially:…”

“…Currently, the overflow mechanism is also being considered as one of the methods for load equalization in self-organizing, selfoptimizing and self-configuring networks [17]- [19]. The overflow mechanism has also found its application in smaller structures, such as switching networks, because an introduction of overflow links in the switches of the first stage leads to a significant decrease in the level of the internal blocking in a switching network [20]- [23].…”

“…In [60], to describe overflow systems, a two-dimensional convolution algorithm is used, while in [61], an overflow system is approximated by an EIG model (Erlang Ideal Grading) [62]. Multiservice switching networks with overflow links are analyzed in [22], [23], [63].…”

Overflows of Elastic Traffic

“…Only when it cannot be serviced in the alternative resources, the call is lost [32]. The main reason for the lack of possibility of servicing a call of a given class in primary or alternative resources is most frequently full occupancy of resources [12,14,15] and threshold mechanisms [7,13,21,22].…”