IP Multicast Architecture Research Articles

Secure receiver access control for IP multicast at the network level: Design and validation

The classical service model of IP multicast is open; anyone can receive multicast data. When using this model, it is impossible to ensure that receivers are authorized to receive the data, or (if appropriate) to generate any revenue from a service based on open multicast. This has resulted in restricted deployment of IP multicast.We have developed a secure IP multicast architecture to enforce receiver access control at two levels: application level and network level. This paper addresses the design and validation of the solution at the network level. The design starts from four assumptions, which express the independence of the network-level solution from the previous work at the application level. At the network level, receiver access control is achieved using two proposed protocols: Secure Internet Group Management Protocol (SIGMP) and Group Security Association Management (GSAM) protocol.SIGMP is an extension to IGMP, in which the messages that are related to secure groups are protected by IPsec Group Security Associations (GSAs). GSAM manages the IPsec GSAs used in SIGMP and couples the network-level access control with the application-level access control.The design requirements for SIGMP and for GSAM are expressed in terms of Design Criteria and Security Goals. These design requirements are then used to justify the final design. Several security properties of GSAM have been formally validated using AVISPA and the remaining security properties of our proposal have been analyzed.

Optimization of manufacturing processes by distributed simulation

The paper describes a simulation-based optimization system for manufacturing processes. The principle suitability of simple Threshold Accepting and Great Deluge Algorithms for optimizing practical manufacturing systems is shown, as well as the possibility of parallelizing of these algorithms. A special IP Multicast architecture is introduced which allows the simulation model to be extended to multiple clients and so the efficiency of the optimization algorithms to be increased by concurrent simulation. Each client can log on or log out at an optimization server at any time so that it should be possible to use the idle computer capacity of a single production department or a whole company. The optimization server is implemented as an experimental option in the simulation system simcron MODELLER®, which is particularly used in electronics and semiconductor manufacturing.

Real-time scheduling by parallel and distributed simulation over IP Multicast

Scheduling optimization of manufacturing processes becomes more and more important. Complex models with a lot of constraints cause a higher computational effort of the simulation. Optimization cycles of heuristic optimization algorithms like genetic algorithms or local search strategies can easily be scheduled in parallel. But recurrent requirements are the distribution of the model, the interchange of the parameters and results. The IP Multicast architecture is an ideal platform for distributing model data over the network. It reduces the network overhead for sending the model to different clients and simplifies also the initial setup between client and server. The client and the server are able to find each other automatically by preconcerted multicast channels. The developed test implementation is designed to work with the simulation system simcron MODELLER and will be used to handle typical optimization tasks like the weekly demand plan of a back-end process or optimal batch sizes for burn-in ovens. It is also suitable for educational purposes and we use it in practical courses where students learn more about factory scheduling. The system offers a high reusability for any operating sequence optimization problem in electronic or semiconductor manufacturing industry, as well as in other fields.

Performance investigations of the IP multicast architecture

The big interest in desktop audio and video conferencing has led to a broad usage of multimedia tools in wide and local area networks. Many of these tools are based upon the IP multicast protocols. The general advantages of multicast services, like the efficient utilization of network resources and thus the possibility to reach arbitrary large numbers of receivers have by now rendered performance considerations of multicast protocols obsolete. Yet, the rapid growth of multicast usage, especially in the IP Internet, may lead to severe congestion problems, if performance trade-offs are not considered carefully in protocol design. In this paper we present performance investigations of the IP multicast architecture with special emphasis on routing protocols. Performance results derived from measurements and simulations will be discussed. Based upon these results, protocol improvements are suggested and evaluated.

Core based trees (CBT)

One of the central problems in one-to-many wide-area communications is forming the delivery tree - the collection of nodes and links that a multicast packet traverses. Significant problems remain to be solved in the area of multicast tree formation, the problem of scaling being paramount among these.In this paper we show how the current IP multicast architecture scales poorly (by scale poorly, we mean consume too much memory, bandwidth, or too many processing resources), and subsequently present a multicast protocol based on a new scalable architecture that is low-cost, relatively simple, and efficient. We also show how this architecture is decoupled from (though dependent on) unicast routing, and is therefore easy to install in an internet that comprises multiple heterogeneous unicast routing algorithms.