Credit-based router-to-router flow control is one main link-level flow control mechanism proposed for Networks on Chip (NoCs). Based on network calculus, we analyze its performance and optimal buffer size. To model the feedback control behavior due to credits, we introduce a virtual network service element called flow controller. Then we derive its service curve, and further the system service curve. In addition, we give and prove a theorem that determines the optimal buffer size guaranteeing the maximum system service curve. Moreover, assuming the latency-rate server model for routers, we give closed-form formulas to calculate the flit delay bound and optimal buffer size. Our experiments with real on-chip traffic traces validate that our analysis is correct; delay bounds are tight and the optimal buffer size is exact.

This paper proposes a credit-based congestion control scheme for multicast communication which employs application-specific processing at intermediate network nodes. The control scheme was designed not only to take advantage of credit-based flow control for unicast communication, but also to achieve flexibility supported by active network technology. The resultant active multicast congestion control scheme is able to meet the different requirements of various multicast applications in terms of reliability and end-to-end latency. The performance of the proposed control scheme was evaluated using both discrete-event simulations and experiments on a prototype active network implementation. The results show that the proposed scheme performs very well in terms of fairness, responsiveness, and scalability. The implementation experiences also confirmed the feasibility of the scheme in practice.

Credit-based electronic payment systems are considered to play important roles in future automated payment systems. Like most other types of payment systems, however, credit-based systems proposed so far generally involve computationally expensive cryptographic operations. Such a relatively heavy computational load is preventing credit-based systems from being used in applications which require very fast processing. A typical example is admission-fee payment at the toll gate of an expressway without stopping a vehicle that travels at a high speed. In this article, we propose a very fast credit-based electronic payment protocol for admission-fee payment. More specifically, we propose a payment system between a high-speed vehicle and a toll gate which uses only very simple and fast computations. The proposed system makes use of an optimized Key Pre-distribution System (or KPS) to obtain high resistance against collusion attacks.

Broadband Integrated Services Digital Network (B-ISDN) is intended to provide various services in telecommunications like voice, video, and data communication. For realizing the B-ISDN network, Asynchronous Transfer Mode (ATM) is one of several data transfer technologies that are proposed and currently being developed. Several flow control methods have been proposed for data cell traffic in ATM network. One of the feedback control mechanisms is credit-based flow control that is proposed to handle an Available Bit Rate (ABR) traffic. The credit based mechanism is applied in Local Area Network (LAN) and usually uses static buffer allocation method. When the conventional credit-based algorithm is applied in the LAN system, the problems such as low utilization of node buffer and large delay of source data will occur. In this paper, we propose a new algorithm that is called stop and release credit method to make credit-based flow control more effective. According to simulation results, proposed method will make high utilization of node buffer and small delay of source data.