Marc Adam Kaplan

Distributed control for PARIS

1 Introduction We describe the control protocols of the PARIS experimental network. This high bandwidth network for integrated communication (data, voice, video) ia currently operational as a laboratory prototype. It will also be deployed within the AURORA Testbed that is part of the NSF/DARPA Gigabit Networking program. The high bandwidth dictates the need of specialized hardware to support faster packet handling and control protocols. A new network control architecture is presented which exploits the specialized hardware in order to support the expected real time needs of future traffic. In particular, since control information can be distributed quickly, decisions can be made based upon more complete and accurate information. In some respects , this has the effect of having the benefits of centralized control (e.g. easier bandwidth resource allocation to connections), while retaining the fault-tolerance and scalability of a distributed architecture. Packet switching networks have changed considerably in recent years. One factor has been the dramatic increase in the capacity of the communication links. The advent of fiber optic media has pushed the transmission speed of communication links to more than a Gigabit/set, representing an increase of several orders of magnitude over typical links in most packet switching networks ([KMS87]) that are still in use today. Increases in link speeds have not been matched by proportionate increases in the processing speeds of communication nodes. Another factor is the changed nature of t&Tic carried by these networks. As opposed to solely data networks, or solely voice networks, it is now accepted that packet switching networks (or variants of packet switching networks like ATM ([K&37])) will form the basis for multimedia high speed networks that will carry voice, data and video through a common set of nodes and links. The disparity between communication and processing speeds suggests that processing may become the main bottleneck in future networks. To avoid this possibility, these networks will be built with high speed switching hardware to off-load the routine packet handling and routing functions from the processor ([CGK88]). In addition, the real time trafEc (e.g. voice) requires that the route selection function be capable of guaranteeing the avaiiability of bandwidth on the links along the chosen path for a particular traffic stream. Otherwise, conges-Permission to copy without fee all or part of this material is granted provided that the copies are not made or dixr-ibuted for direct commercial advantage, the ACM copyright notice and the title of …

The plaNET/ORBIT High Speed Network

This paper presents an overview of the plaNET/ORBIT Gigabit networking system being developed at IBM. It identifies the various network components and their functionality, and describes how the many services provided by the network are supported. The paper focuses on providing a general view on how the different components operate and interact with each other, rather than on giving detailed technical descriptions of their implementations. Instead, pointers to relevant publications are used to allow interested readers to find additional details.

A distributed control architecture of high-speed networks

A control architecture for a high-speed packet-switched network is described. The architecture was designed and implemented as part of the PARIS (subsequently plaNET and BBNS) networking project at IBM. This high bandwidth network for integrated communication (data, voice, video) is currently operational as a laboratory prototype. It will also be deployed within the AURORA Testbed that is part of the NSF/DARPA gigabit networking program. The high bandwidth dictates the need for specialized hardware to support faster packet handling for both point-to-point and multicast connections. A faster and more efficient network control is also required in order to support the increased number of connections and their changing requirements with time. The new network control architecture presented exploits specialized hardware, thereby enabling tasks to be performed faster and with less computation overhead. In particular, since control information can be distributed quickly using hardware packet handling mechanisms, decisions can be made based upon more complete and accurate information. In some respects, this has the effect of having the benefits of centralized control (e.g., easier bandwidth resource allocation to connections), while retaining the fault tolerance and scalability of a distributed architecture. >

Policy-based information lifecycle management in a large-scale file system

Policy-based file lifecycle management is important for balancing storage utilization and for regulatory conformance. It poses two important challenges, the need for simple yet effective policy design and an implementation that scales to billions of files. This paper describes the design and an innovative implementation technique of policy-based lifecycle management in a prototype built as a part of IBMs new SAN file system. The policy specification leverages a key abstraction in the file system called storage pools and its ability to support location independence for files. The policy implementation uses an innovative new technique that combines concurrent policy execution and a policy decisions cache, to enable scaling to billions of files under normal usage patterns.

An architecture for lifecycle management in very large file systems

We present a policy-based architecture STEPS for lifecycle management (LCM) in a mass scale distributed file system. The STEPS architecture is designed in the context of IBMs SAN file system (SFS) and leverages the parallelism and scalability offered by SFS, while providing a centralized point of control for policy-based management. The architecture uses novel concepts like policy cache and rate-controlled migration for efficient and non-intrusive execution of the LCM functions, while ensuring that the architecture scales with very large number of files. The architecture has been implemented and used for lifecycle management in a distributed deployment of SFS with heterogeneous data. We conduct experiments on the implementation to study the performance of the architecture. We observed that STEPS is highly scalable with increase in the number as well as the size of the file objects hosted by SFS. The performance study also demonstrated that most of the efficiency of policy execution is derived from policy cache. Further, a rate-control mechanism is necessary to ensure that users are isolated from LCM operations.

Multicast group membership management in high speed wide area networks

An application for multicast service for high-speed WANs (wide area networks) which is capable of exploiting multicast hardware is described. Modularity and low cost area achieved by assigning to distinct components the separate problems of (1) naming groups, (2) finding group members in a network, (3) configuring multicast hardware, and (4) delivering multicast messages in sequence. The overall organization of the service is given, along with the methods used to solve the first two subproblems.<<ETX>>

A new parallel algorithm for CRC generation

Cyclic redundancy check (CRC) is one of the most important error-detection schemes used in digital communications. A new parallel algorithm for CRC generation and its software as well as hardware implementation is described. For the software implementation, this paper has focused on the 32-bit CRC used in the Ethernet, computed on a general purpose PowerPC microprocessor with the new AltiVec technology. A speedup by a factor of 4.57 over the standard table-lookup algorithm was obtained. A hardware implementation of the algorithm is then discussed, which yields an unlimited speed-up potential over the bit-wise serial algorithm.

Multicast group membership management

Multicast services, assisted by special hardware, are being considered as a part of high-speed wide-area networks (WANs) in order to support new generations of multiuser applications. This paper describes an application multicast service for high-speed WANs which is capable of exploiting multicast hardware. Indeed, this research was conducted in context of the spanning tree hardware structure of PARIS and of plaNET, the pioneering broadband experimental networks that predated ATM. The results of this research were also included in IBMs ATM, called Networking BroadBand Services (NBBS).We achieve modularity and low cost by assigning to distinct components the separate problems of: 1) naming groups; 2) finding group members in a network; 3) configuring multicast hardware; and 4) delivering multicast messages in sequence. This modularity enables, for example, both the multicast to a group to which the user initiates the joining (formed by using 1 and 2 above), on one hand, and to groups computed by the source on the other hand. We give the overall organization of our service and then describe in detail the methods used to solve the first two of the subproblems.

Cryptographic Containers and the Digital Library

Today, information is distributed on the Internet and other communication infrastructures mainly for free. However, once information or digital contents is assigned some value, a means is needed to protect its copyrights and control its use.

Efficient transport and distribution of network control information in NBBS

With the advances in fiber-based transmission systems that operate at gigabit rates and with the introduction of high-speed networks, the course of communication and computer technologies has changed forever. This change requires that new attention be focused first on the creation, then on the control of networks, which now contain high-speed links and integrate heterogeneous traffic. IBMs Networking BroadBand Services (NBBS) architecture has been designed to enable this networking revolution and, in particular, is designed for the high-speed, multimedia networks needed by emerging applications. In this paper, we present the Rapid Transport Protocol (RTP). Its simple and efficient mechanisms enable NBBS control information to be transported and distributed, taking advantage of high-speed links by eliminating as much nodal processing as possible. RTP provides point-to-point and point-to-multipoint transport services with a reliable delivery option. In addition, we present a simple and efficient mechanism for fast dissemination of time-critical network configuration and path update messages to every node in an NBBS network, making use of RTP.