摘要:

AbstractPerformance studies on LAN/MAN‐BISDN interworking have mainly focused on the requirements of isochronous and connectionless services. In this paper we extend performance results to cover also the case of non‐isochronous connection oriented (CO) services supported by the queued arbitrated (QA) mode of access of the DQDB protocol. Using this case we stress the more general issue of service integration impact on the interworking unit (IWU) architecture design in terms of protocol stacks and expected performance. We herein evaluate the performance of IWU architectures tailored to relay information in the lowest possible layer while implementing several service priority schemes and buffer management policies towards QoS objectives. The conditions under which the IWU design is efficient regarding performance, protocol complexity and implementation cost in this integrated services environment are identif

ISSN:1074-5351    

DOI:10.1002/dac.4500080102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractAnN × Nswitching element with output queueing, as used in a large ATM switching network, is considered. All the inlets of the switching element are synchronized on ‘minislots’, where a minislot is the fixed‐length time unit for the transmission of one ‘minicell’. When entering the switching network, an ATM cell is converted into a ‘minicell‐train’, consisting of a fixed number of minicells. Using an active/silent model, it is assumed that on each inlet of the switching element, the number of minicelltrains in an active period and the length of a silent period are both geometrically distributed, and the arriving minicell‐trains are uniformly distributed among all the outlets. The performance of the switching element can be obtained by analysing one single output queue, which is modeled as a discrete‐time single‐server queuing system with train arrivals. In this paper, an upper bound and an approximate expression for the mean queue length are derived. More importantly, an analytical method is developed to obtain a tight upper bound and a good approximation for the tail distribution of the queue length. This analytical method is very useful in buffer dimens

ISSN:1074-5351    

DOI:10.1002/dac.4500080103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractA distributed time‐slot assignment protocol is developed for a mobile multi‐hop broadcast packet radio network, using time division multiple access channel access and virtual circuit switching. The protocol eliminates the single point failure mode of centralized network management and the delays of centralized processing. It is applicable to the user‐to‐user communications functions of such systems as the U. S. Army's enhanced position location and reporting system (EPLRS). The important functions of the distributed protocol, including time‐slot assignment, virtual circuit set‐up, and network synthesis, are identified, and implementing algorithms are presented and verified. The performance analysis of the protocol is divided into two parts. In this paper, Part 1 of the performance analysis, the capacity of a network using this protocol is studied and a tool is developed to design the network capacity by trading off among the network area, the transmission range, and the number of packet radio units. Since these results are not in closed form, numerical results provide insight into these parameters. In Part 2 the network set‐up time and network data rate are analysed and a hierarchical architecture for the distributed protocol is proposed

ISSN:1074-5351    

DOI:10.1002/dac.4500080104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractIn this, the second part of a two‐part paper, the required time for establishing a mobile packet radio network using the virtual circuit and time division multiple access protocol developed in Part 1 is analysed. Tools are developed to determine the virtual circuit and network set‐up times in terms of the channel bandwidth allocated to establish and maintain the network. The tools are then extended to include the effects of user mobility. Then these results are combined with the network capacity results of Part 1 to analyse the trade‐off between the data rate and set‐up time of the network. Next a hierarchical architecture is proposed and the network data rate versus set‐up time trade‐off of this architecture is analysed using these tools. This architecture is shown to both provide a higher data rate and establish faster than flat networks of the same numb

ISSN:1074-5351    

DOI:10.1002/dac.4500080105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractThe cross‐correlation of frequency hopping sequences obtained from non‐binarym‐sequences represented as vectorm‐sequences is developed. Preferred pairs of these vectorm‐sequences then yield vector or frequency hoppingm‐sequences which are shown to have small three‐and four‐level cross‐correlation values. Modified preferred pairs are developed that yield frequency hoppingm‐sequences with reduced pea

ISSN:1074-5351    

DOI:10.1002/dac.4500080106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractBroadband packet networks based on asynchronous transfer mode (ATM) are expected to provide a wide range of services, including motion video, voice, data and image. When these networks become prevalent, some applications such as motion video and high‐speed LAN interconnections will place a very large bit rate requirement on the channels. Currently, the physical layer supported by the synchronous optical network (SONET) allows the transmission of up to 2.4 Gbit/s with the OC‐48 optical interface. However, it is not feasible for the electronic packet switch to route packets at this rate on a single link. In this paper we present a design of a broadband packet switch that uses multiple links in parallel to realize a high‐speed channel. This implementation permits the switch to operate at the lower link rate, which can be at 150 Mbit/s, while having the ability to support a virtual circuit at a higher rate (up to 2.4 Gbit/s). The main contribution of the design is that packet sequence on a channel is still maintained even though packets are allowed to use any of the links belonging to the same channel. Besides allowing the switch to function at a slower rate than the transmission channel rate, the implementation of the multilinks benefits from statistical multiplexing gain. Analytical results show the performance advantages of multilink design with respect to delay, throughput and packet loss probab

ISSN:1074-5351    

DOI:10.1002/dac.4500080107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

ISSN:1074-5351    

DOI:10.1002/dac.4500080101

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY