There is a growing demand that mobile networks should provide quality-of-service (QoS) to mobile users since portable devices become popular and more and more applications require real-time services. Providing QoS to mobile hosts is very difficult due to mobility of hosts. The resource ReSerVation Protocol (RSVP) establishes and maintains a reservation state to ensure a given QoS level between the sender and receiver. However, RSVP is designed for fixed networks and thus it is inadequate in wireless mobile networking environments. In this paper, we propose a resource reservation protocol for mobile hosts in mobile networks. The proposed protocol extends the RSVP by introducing RSVP agents in local networks to manage the reservations. The proposed protocol reduces packet delay, bandwidth overhead, and the number of RSVP messages to maintain reservation states. We examined the performance of the proposed protocol by simulation and we got an improved performance over the existing protocols.

In this paper, we propose a synchronous reservation protocol that is efficient for supporting variable-sized messages in a wavelength division multiplexing (WDM)-based local network using a passive star topology. A control channel is used to coordinate message transmission on data channels. Time is slotted with fixed-sized slots. The network can accommodate a variable number of nodes and operate independently of the change in the number of nodes. Therefore, any "new" node can join the network anytime without network re-initialization. Moreover, with the protocol, we can avoid data channel and destination conflicts. We analyze the performance according to the variation of the end-to-end propagation delay with respect to one slot time, and validate the results by simulation.

In this paper, we investigate the performance of Fast Reservation Protocols (FRP) for burst-level bandwidth allocation in ATM networks. FRP schemes can be classified into delayed transmission (DT) and immediate transmission (IT) methods according to reservation procedure. Moreover, according to the responsibility for negative acknowledgment (NAK) cell generations when burst blocking occurs, FRP schemes can be further classified into blocking node NAK (BNAK) and destination node NAK (DNAK) schemes. We analize the FRP schemes with different reservation and NAK methods for single node and multihop network models, respectively. We then discuss the dependence of performance for each FRP scheme on propagation delay, peak rate, and the number of hops.

This paper proposes a medium access control (MAC) protocol for single-hop WDM star-coupler networks, in which the number of stations is larger than the number of channels and the stations have arbitrary distances to the star coupler. The proposed protocol has one control channel for reserving the slots of data channels and several data channels which are used to transmit traffic. This paper also suggests a scheme that accomplishes load balancing among data channels for arbitrary traffic patterns between stations. Since this load balancing scheme diminishes an influence that traffic patterns have on the performance of the proposed MAC protocol, the proposed system is appropriate for systems which have asymmetric traffic intensity between stations. Throughput and mean message delay of the MAC protocol are analyzed using a discrete time Markov process and a D/G/1 queue with batch arrivals. The numerical results show that the performance is improved as the message length increases, the maximum round-trip propagation delay decreases, and the number of data channels increases.

We propose burst based bandwidth reservation method called FRP (Fast Reservation Protocol) in ATM LAN with general topology, and evaluate its performance. In FRP, the bandwidth is allocated on each link on burst basis, not on call basis. This enables an effective use of network resources when it is applied to highly bursty traffic, which can be typically found in data communications. The problem of FRP is that VCs traversing the different number of links experience different blocking probabilities as can be found in the conventional circuit-switching networks. In this paper, we treat a fairness issue in FRP-based ATM local area networks. The Max-Min flow control is adopted as the fair bandwidth allocation method to accomplish the fairness in the throughput. However, the original Max-Min flow control works in a centralized fashion, which is not desirable in the FRP-based ATM LAN. We therefore propose a "semi"-distributed Max-Min flow control suitable to FRP, in which each switch maintains its own local information about bandwidth usage of the connected links. Through simulation experiments, we show that the proposed semi-distributed Max-Min flow control can achieve the fairness among VCs as the original Max-Min flow control when the propagation delays are not large and the number of VCs is not so much.

A local area network (LAN) can now provide high-speed data communications in a local area environment to establish distributed processing among personal computers and workstations, and the need for interconnecting LANs, which are geographically distributed, is naturally arising. Asynchronous Transfer Mode (ATM) technology has been widely recognized as a promising way to provide the high-speed wide area networks (WAN) for Broadband Integrated Services Digital Network (B-ISDN), and the commercial service offerings are expected in the near future. The ATM network seems to have a capability as a backbone network for interconnecting LANs, and the LAN interconnection is expected to be the first service in ATM networks. However, there remain some technical challenges for this purpose; one of the main difficulties in LAN interconnection is the support of connectionless traffic by the ATM network, which is basically a connection-oriented network. Another one is the way of achieving the very high-speed data transmission over the ATM network. In this paper, we first discuss a LAN internetworking methodology based on the current technology. Then, the recent deployments of LAN interconnection methods through B-ISDN are reviewed.