Introduction of circuits into the packet-switched network influences the QoS of the packets transported hop by hop. This report focuses on the correct dimensioning of two types of circuits in a butterfly network with different loads. The results show that depending on the load and routing mechanism, introduction of circuits can bring benefits for both the packets transported by the circuits and...

Recently, switched systems have been found in many practical applications such as in communication network dynamics, robot manipulators, traffic management, etc. In this paper, we study the stability of time-varying linear switched systems under perturbations that satisfy linear growth condition, which is not available in current literature. By introducing a new Liao-type exponent for time-vary...

"Transparent network" and "all-optical network" are not synonyms. Optical transparency has to be sacrificed in optical logic elements. The paper presents author’s original view on future (all) optical packet-switched network which is based on a clear distinction within dual nature of optical signals: analogue and transparent features of the signal in optical frequency domain from one side, and ...

Switched networks have an increasingly important role in real-time communications. The IEEE Ethernet standards have defined prioritized traffic (802.1p) and other QoS mechanisms (802.1q). The Avionics FullDuplex Switched Ethernet (AFDX) standard defines a hard real-time network based on switched Ethernet. Clock synchronization is also an important service in some real-time distributed systems b...

In this paper, we show how Network Calculus can be used to determine whether a switched network may satisfy the time constraints of a real-time application. If switched architecture are interesting in the sense that they offer flexible design and may eliminate collisions in Ethernet-based network, they are not guaranteeing end-to-end performances (in particular in terms of delay), especially wh...

Circuit-switched networks are emerging as an attractive alternative to conventional packetswitched ones for some types of application, particularly ones involving transferring a large volume of data. The ESLEA Project will use the UKLight circuit-switched network, and its analogues overseas, to demonstrate the usefulness of circuit-switched networks in several applications disciplines. A circui...

Existing cell switched and packet switched transmission systems have difficulties to support real-time data transfer because the queuing characteristics and load variations in the network nodes are a handicap for it. With our interval-based transmission control method the data stream behavior is regulated in each network node and a data stream dependent time parameter adjustment is performed in...

In an optical mesh network, backup channels are shared between multiple lightpaths to reduce restoration capacity overhead. The sharability of channels is usually constrained by the mandate to provide 100% recovery of all lightpaths affected by any single event failure in the network. This paper proposes a pool based channel reservation scheme that is optimal when the set of primary and backup ...

We consider a switched network (i.e. a queueing network in which there are constraints on which queues may be served simultaneously), in a state of overload. We analyse the behaviour of two scheduling algorithms for multihop switched networks: a generalized version of max-weight, and the α-fair policy. We show that queue sizes grow linearly with time, under either algorithm, and we characterize...

This paper describes the lightpath planning and monitoring software suite developed specifically for managing lightpaths in the hybrid SURFnet6 network and the NetherLight optical exchange point. Lightpaths are high bandwidth circuits with deterministic quality of service characteristics. These lightpaths are used by researchers in demanding network projects. The concept of the high bandwidth l...