Abstract:
A cascadable floor module for supporting scalable electronics systems is disclosed. The cascadable floor module includes a top surface for ambulation and supporting one or more electronics towers. On the top surface are one or more vertical transport channels for electrically connecting to the electronics towers. Below the top surface, an interior volume houses electrical connections to the vertical transport channels. When a plurality of cascadable floor modules are aligned with their top surfaces flush, the top surfaces form a floor upon which service personnel may walk. All electrical connections are made in the interior volume below the top surface.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    Embodiments of the present invention claim priority from U.S. Provisional Application Serial No. 60/204,446 entitled “Cartridge-Based, Geometry-Variant Scalable Electronics With Synthetic Sentience,” filed May 15, 2000, and are related to U.S. utility patent applications entitled “System and Method for Cartridge-Based, Geometry-Variant Scalable Electronics,” attorney docket no. 079374/0101, filed ______; “Apparatus, System, and Method for Hybrid-Geometry Resource Cartridge-Based, Geometry-Variant Scalable Electronic Systems,” attorney docket no. 079374/0103, filed ______; “Apparatus and Method for Scalable Interconnection Networks in Electronic Systems,” attorney docket no. 079374/0104, filed ______; and “Hexagonal Structures for Scalable Electronic Systems,” attorney docket no. 079374/0105, filed ______. The content of these applications are incorporated by reference herein. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    The present invention relates, generally, to scalable electronic systems, and, in preferred embodiments, to apparatus and methods for scaling electronic systems using cascadable floor modules.  
           [0004]    2. Description of the Related Art  
           [0005]    Over the last few years there has been tremendous growth in the awareness of, and the desire to utilize, on-line resources including the Internet and the World Wide Web. New on-line users are jumping in with enthusiasm and high expectations based upon the promises of cyberspace. Business has rushed in as well, with major media companies and publishers, as well as novice entrepreneurs, setting up and championing their own web sites.  
           [0006]    The Internet, as a digital resource, is now established in many parts of the world, and is increasingly viewed as an essential utility such as water or electrical power. Furthermore, the global demand for high speed transmission and manipulation of increasingly complex data is unlikely to wane in the foreseeable future. Individuals, corporations, universities, and government agencies like the Pentagon are demanding increased communications speed and computing power to cope with the greater volume of data and the increased complexity of data handling requirements, and will likely purchase as much communication speed and computing power as they can afford because of the substantial revenues or operational efficiencies that accrue when large global demands are satisfied.  
           [0007]    However, improvements in the infrastructure needed to support such requirements have not kept pace with the demand. Growth in the hardware market is driven by growing demand for multimedia applications. Demand for multimedia applications is the result of a convergence of expanded processing power, better software programming and the spread of telecommunications computing networks.  
           [0008]    Telephone and cable companies face a continuing need to upgrade their switching and distribution networks in response to this high demand. Corporate and institutional local area networks and computing facilities are often overwhelmed by data because of equipment that was not designed to handle the data requirements needed to remain competitive in today&#39;s industrial and social climate. For these businesses, and soon the information economy in general, system crashes and slowdowns are likely to increase as current trends continue. The problem reaches far beyond the confines of individual, institutional, corporate, or even national boundaries.  
           [0009]    As noted above, the use of, and need for, inexpensive, ubiquitous, and uninterrupted processing power and communications bandwidth is likely to continue into the foreseeable future. As telecommunications networks increase their throughput capacity, becoming more affordable and accessible, the evolutionary progression from stand-alone computers, to network computers, to on-line tele-computing is also likely to accelerate. However, this progression will require new solutions to improve the current infrastructure, which is perilously overburdened at every level.  
           [0010]    One methodology that is being developed to increase processing power and bandwidth is parallel computing. Parallel computing uses multiple processors working in parallel on a single computing task. These processors can be linked together within a single computer, or they can be housed separately in a cluster of computers that are linked together in a network. The advantage of parallel computing over traditional, single-processor computing is that it can tackle problems faster and with greater power. For parallel computing to work, however, software and operating systems had to be re-developed within the context of multiple processors working together on one or more tasks. Standards have been developed which ensure that parallel computing users can achieve scalable software performance independent of the machine being used.  
           [0011]    As technology has evolved, parallel processing has become a significant segment of the server market, and a growing segment of the desktop PC and workstation market. Sales of workstations and PCs have grown rapidly as the cost of the machines has dropped and their power and functionality have increased. Also fueling this trend has been the proliferation of graphically-oriented, scalable operating systems, such as Sun Microsystems Solaris, Unix, and Linux. Advanced parallelizing resources, such as Portland Group&#39;s Fortran and C++ compilers, provide a development environment for porting existing code into parallel scalable software, and for creating new software which maximizes the benefits of distributed processing. The overall effect of these changes has been to deliver increased computing power and flexibility directly to the end user via a desktop computer, while enabling the user to access and process large amounts of data via the cluster or network to which they are connected.  
           [0012]    However, conventional network architectures yield communication bandwidths that make highly distributed numerical processing inefficient. Typical parallel programming environments have communications delays of several milliseconds. Fully exploiting the underlying advantages of parallel computing is a challenge that has eluded computer science and applications developers for decades. Developers have had to choose between the tightly coupled architecture and high efficiency of the supercomputer, or the flexibility, scalability, and cost performance of a cluster of PCs.  
           [0013]    The execution of computer instructions over multiple processors in supercomputers and massively parallel processors has historically been accomplished by duplicating critical hardware such as memory and input-output (I/O) subsystems. These types of systems offer excellent performance, but are expensive. Moreover, low-volume manufacturing results in a significant cost/performance disadvantage, and engineering lag time may cause a technological gap between products finally appearing on the market and currently available microprocessors.  
           [0014]    Networks of servers, workstations, and PCs may offer a cost-effective and scalable alternative to monolithic supercomputers. Using new operating systems and compilers, the bundling together of a cluster of desktop PCs and/or workstations into a parallel system has proven to be an effective solution for meeting the growing demand for computing power. Scalability, the ability to add additional processing nodes to a computing system, may be particularly essential for those systems involved in the delivery of World Wide Web information, due to the fact that Web traffic and the number of users is increasing dramatically. Future Web servers will have to deliver more complex data, voice, and video as subscriber expectations increase. Large scale systems are being built that consist of clusters of low cost computers that communicate with one another through a system area network (SAN). Clusters enable scalability to thousands of nodes, and can exploit the parallelism implicit in serving multiple simultaneous users or in processing large queries involving many storage devices. Thus, clusters can operate as a single system for tasks such as database and on-line transaction processing.  
           [0015]    As compared to supercomputers and mainframes, cluster computing systems have the advantages of physical modularity, insulation from obsolescence, physical and logical scalability (expandability), physical and logical upgradability, and improved cost performance. However, cluster computing systems generally have less communication bandwidth, more contingencies and bottlenecks in the network protocol, many redundant and unused components, and a larger physical footprint.  
         SUMMARY OF THE DISCLOSURE  
         [0016]    Therefore, it is an advantage of embodiments of the present invention to provide an apparatus and method for scaling electronics systems using cascadable floor modules that has the modularity, flexibility, upgradability, and cost performance of a scaleable cluster array, while yielding the physical compactness, inter-processor communications, and extended computational capabilities of supercomputers, array processors, and mainframes.  
           [0017]    It is a further advantage of embodiments of the present invention to provide an apparatus and method for scaling electronics systems using cascadable floor modules that allows entire electronics towers to be cascaded without having to route wiring bundles overhead or along personnel access routes.  
           [0018]    It is a further advantage of embodiments of the present invention to provide an apparatus and method for scaling electronics systems using cascadable floor modules that provides service personnel with room to perform maintenance and replace resource cartridges.  
           [0019]    These and other advantages are accomplished according to a cascadable floor module for supporting scalable electronics systems. The cascadable floor module includes a top surface for ambulation and supporting one or more electronics towers. On the top surface are one or more vertical transport channels for electrically connecting to the electronics towers. Below the top surface, an interior volume houses electrical connections to the vertical transport channels. When a plurality of cascadable floor modules are aligned with their top surfaces flush, the top surfaces form a floor upon which service personnel may walk. All electrical connections are made in the interior volume below the top surface.  
           [0020]    These and other objects, features, and advantages of embodiments of the invention will be apparent to those skilled in the art from the following detailed description of embodiments of the invention, when read with the drawings and appended claims. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]    [0021]FIG. 1 is a perspective view of a cartridge-based, geometry-variant scalable parallel computer/server (modular electronics cluster) according to an embodiment of the present invention.  
         [0022]    [0022]FIG. 2 is a perspective view illustrating a resource cartridge and a chassis of a modular electronics cluster according to an embodiment of the present invention connected through ports or lateral transport channels utilizing conventional blind-mount connector technology.  
         [0023]    [0023]FIG. 3 is a perspective view illustrating a resource cartridge and a chassis of a modular electronics cluster according to an embodiment of the present invention connected through ports or lateral transport channels utilizing wireless communication links that convert between electronic signals and optical signals.  
         [0024]    [0024]FIG. 4 is a perspective view of upper vertical transport channels in a socket configuration on a cartridge-based modular electronics cluster according to an embodiment of the present invention.  
         [0025]    [0025]FIG. 5 is a perspective view of lower vertical transport channels in a pin configuration on a cartridge-based modular electronics cluster according to an embodiment of the present invention.  
         [0026]    [0026]FIG. 6 is a perspective view of a cartridge-based modular electronics cluster that includes a data transport unit insertable into or removable from the chassis according to an embodiment of the present invention.  
         [0027]    [0027]FIG. 7 is a perspective view of a modular electronics cluster that includes resource cartridges insertable into or removable from a data transport unit without a chassis according to an embodiment of the present invention.  
         [0028]    [0028]FIG. 8 is a perspective view of a modular electronics cluster comprised of six resources and a data transport unit, symbolically represented as six spheres surrounding and connected to a central sphere according to an embodiment of the present invention.  
         [0029]    [0029]FIG. 9 is a perspective view of a symbolic representation of a modular electronics cluster enclosed in a hexagonal structure according to an embodiment of the present invention.  
         [0030]    [0030]FIG. 10 is a perspective view of a symbolic representation of a stack of six modular electronics clusters connected for greater computing power, wherein each modular electronics cluster is electrically connected to adjacent modular electronics clusters through vertical transport channels in the data transport unit (the central sphere) according to an embodiment of the present invention.  
         [0031]    [0031]FIG. 11 is a perspective view of a vertical stack of six cartridge-based modular electronics clusters, each modular electronics cluster connected to an adjacent modular electronics cluster through vertical transport channels in a data transport unit according to an embodiment of the present invention.  
         [0032]    [0032]FIG. 12 is a perspective view of a resource cartridge including vertical transport channels which allow multiple resource cartridges to be stacked and electrically connected without need for a chassis or a separate data transport unit according to an embodiment of the present invention.  
         [0033]    [0033]FIG. 13 is a perspective view of a stack of resource cartridges supported by a base module according to an embodiment of the present invention.  
         [0034]    [0034]FIG. 14 is a perspective view of a plurality of resource cartridges stacked vertically and connected laterally through lateral transport channels according to an embodiment of the present invention.  
         [0035]    [0035]FIG. 15 is a perspective view of three stacks of multiple resource cartridges contained in a chassis which includes a base module and vertical extensions according to an embodiment of the present invention.  
         [0036]    [0036]FIG. 16 is a perspective view of a rectangular-shaped modular electronics cluster with resource cartridges plugged into slots in the front of the chassis according to an embodiment of the present invention.  
         [0037]    [0037]FIG. 17 is a symbolic representation of communication paths that may exist between resources within a cluster, and between resources in adjacent clusters, in embodiments of the present invention.  
         [0038]    [0038]FIG. 18 is a symbolic representation of connectivity paths that may exist for each resource in embodiments of the present invention.  
         [0039]    [0039]FIG. 19 illustrates how two PSB-64 Bridge Chips may be implemented to provide connectivity for each resource in embodiments of the present invention.  
         [0040]    [0040]FIG. 20 is a perspective view of six hexagonal modular electronics clusters in a vertical stack and supported by a base module and a floor module according to an embodiment of the present invention.  
         [0041]    [0041]FIG. 21 is a perspective view of a plurality of vertical stacks of modular electronics clusters, each vertical stack connected to other vertical stacks through floor modules according to an embodiment of the present invention.  
         [0042]    [0042]FIG. 22 illustrates how a vertical stack of resource cartridges can be laterally scaled by placing other vertical stacks of resource cartridges in close proximity and connecting the lateral transport channels of adjacent resource cartridges according to an embodiment of the present invention.  
         [0043]    [0043]FIG. 23 illustrates how a vertical stack of cartridge-based modular electronics clusters is laterally scalable to modular electronics clusters in other vertical stacks through lateral transport channels that connect adjacent resource cartridges through the data transport unit, base modules, and floor modules according to an embodiment of the present invention.  
         [0044]    [0044]FIG. 24 illustrates both the vertical and horizontal scalability of resources according to embodiments of the present invention.  
         [0045]    [0045]FIG. 25 is a top view illustrating the lateral scalability of a triangular modular electronics cluster according to an embodiment of the present invention.  
         [0046]    [0046]FIG. 26 is a top view illustrating the lateral scalability of a square modular electronics cluster according to an embodiment of the present invention.  
         [0047]    [0047]FIG. 27 is a top view illustrating the lateral scalability of a hexagonal modular electronics cluster according to an embodiment of the present invention.  
         [0048]    [0048]FIG. 28 is a perspective view of a multi-sided cartridge-based modular electronics cluster whose shape approaches that of a circle according to an embodiment of the present invention.  
         [0049]    [0049]FIG. 29 is a top view of six resource cartridges coupled to a data transport unit and arranged in an overlapping manner to improve compactness in the horizontal dimension while maintaining the rectangular shape of the resource cartridges.  
         [0050]    [0050]FIG. 30 is a perspective view of a hybrid-geometry resource cartridge according to an embodiment of the present invention.  
         [0051]    [0051]FIG. 31 is a perspective view of two hybrid-geometry resource cartridges arranged in an alternating orientation to improve compactness according to an embodiment of the present invention.  
         [0052]    [0052]FIG. 32 is a perspective view of six hybrid-geometry resource cartridges arranged in an alternating orientation and connected to a data transport unit to form a single hybrid-geometry resource cartridge-based modular electronics cluster according to an embodiment of the present invention.  
         [0053]    [0053]FIG. 33 is a perspective view of a stack of multiple hybrid-geometry resource cartridge-based modular electronics clusters according to an embodiment of the present invention.  
         [0054]    [0054]FIG. 34 is a perspective view, partially broken away, of hybrid-geometry resource cartridges inserted into a chassis according to an embodiment of the present invention.  
         [0055]    [0055]FIG. 35 is a perspective view of hybrid-geometry resource cartridges and a data transport unit inserted into a chassis according to an embodiment of the present invention.  
         [0056]    [0056]FIG. 36 is a perspective view of rectangular-shaped hybrid-geometry resource cartridges connectable to a data transport unit without a chassis according to an embodiment of the present invention.  
         [0057]    [0057]FIG. 37 is a perspective view of offset lateral transport connectors on hybrid-geometry resource cartridges and a data transport unit according to an embodiment of the present invention.  
         [0058]    [0058]FIG. 38 is a perspective view of lateral transport connectors on a data transport unit designed with two sets of duplicated pins, each set of pins being rotated  180  degrees from the other set according to an embodiment of the present invention.  
         [0059]    [0059]FIG. 39 is a perspective view of lateral transport connectors on a data transport unit having one placement, but two pin orientations, according to an embodiment of the present invention.  
         [0060]    [0060]FIG. 40 is a perspective view of multiple lateral transport connectors located in a vertical arrangement on each side of a data transport unit according to an embodiment of the present invention.  
         [0061]    [0061]FIG. 41 is a top view of multi-sided resource cartridges designed using only adapter geometries and coupled to a data transport unit according to an embodiment of the present invention.  
         [0062]    [0062]FIG. 42 is a perspective view of hybrid-geometry resource cartridges coupled to a hexagonal data transport unit within a chassis, with the top of chassis removed for clarity, illustrating how a data transport unit can be removed through cartridge openings according to an embodiment of the present invention.  
         [0063]    [0063]FIG. 43, is a perspective view of a vertical stack of three modular electronics clusters, shown without a chassis for clarity, illustrating that if the data transport unit on the bottom or middle modular electronics cluster needs to be replaced, side removal according to an embodiment of the present invention will allow the data transport unit to be swapped out without having to remove the uppermost modular electronics clusters. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0064]    In the following description of preferred embodiments, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the preferred embodiments of the present invention.  
         [0065]    The Internet, as a digital resource, is now established in many parts of the world. Individuals, corporations, universities, and government agencies like the Pentagon are demanding increased communications speed and computing power to cope with the greater volume of data and the increased complexity of data handling requirements.  
         [0066]    One methodology that is being developed to increase processing power and bandwidth is parallel computing. Parallel computing uses multiple processors working in parallel on a single computing task. These processors can be linked together within a single computer, or they can be housed separately in a cluster of computers that are linked together in a network.  
         [0067]    Using new operating systems and compilers, the bundling together of a cluster of desktop PCs and/or workstations into a parallel system has proven to be an effective solution for meeting the growing demand for computing power. Scalability, the ability to add additional processing nodes to a computing system, may be particularly essential for those systems involved in the delivery of World Wide Web information, due to the fact that Web traffic and the number of users is increasing dramatically. Large scale systems are being built that consist of clusters of low cost computers that communicate with one another through a system area network (SAN). Clusters enable scalability to thousands of nodes, and can exploit the parallelism implicit in serving multiple simultaneous users or in processing large queries involving many storage devices.  
         [0068]    Embodiments of the present invention relate to systems and methods for volumetrically cascadable geometry-variant electronics. Preferred embodiments of the present invention combine the enhanced communications architecture of a Massively Parallel Processor with the price/performance, flexibility, and standardized programming interfaces of a scalable cluster. Furthermore, embodiments of the present invention are capable of utilizing well known programming interfaces to ensure software portability over a wide range of different systems, and also eliminate the redundant hardware components in a conventional cluster.  
         [0069]    It should be noted that although embodiments of the present invention are described herein with respect to a generic parallel computing system, embodiments of the present invention are applicable to a wide variety of general applications that employ scalable electronics of any type and function. More specifically, embodiments of the present invention are applicable to multimedia, telecommunications, digital processing systems, and the like. “Multimedia,” as defined herein, includes combinations of data, text, voice, image and video in all forms, including computer generated graphics and effects, film/video/music production, and media on demand. Embodiments of the present invention are also applicable to evolving technologies that include, but are not limited to, WebTV™, Broadband cable services, on-line commerce, and the internet service provider (ISP) business, as well as their enabling technologies.  
         [0070]    Furthermore, although embodiments of the present invention are described herein with respect to a generic parallel computing system, embodiments of the present invention are applicable to a wide variety of hardware configurations that include, but are not limited to, desktop personal computers (PCs), network computers, workstations, systems integration computers (servers), and large-scale industrial computers.  
       Geometry-Variant Scalable Electronics  
       [0071]    [0071]FIG. 1 illustrates an example of a cartridge-based, geometry-variant scalable parallel computer/server, or more generally a modular electronics cluster  10 , according to a preferred embodiment of the present invention. It should be understood that the hexagonal shape of the embodiment of FIG. 1 is merely exemplary, and that other geometries fall within the scope of embodiments of the present invention. In the embodiment of FIG. 1, modular electronics cluster  10  is comprised of a receptacle and one or more resource cartridges  14 . In FIG. 1, the receptacle is a chassis  12 .  
         [0072]    Resource cartridges  14  contain resources (electronic components) which may include, but are not limited to, processors, digital signal processors, programmable logic arrays, memory, tape transport devices, display devices, audio devices, modem connectors, optical couplers, wireless receivers/transmitters, and the like. In the embodiment of FIG. 1, resource cartridges  14  align with and plug into chassis  12  through openings in the faces of chassis  12 . Connectivity between resource cartridges  14  and chassis  12  may be effected by ports or lateral transport channels utilizing conventional blind-mount connector technology or the like (see FIG. 2). In addition to utilizing physical hardwire connectors, connectivity may also be achieved through wireless communication links, optical couplers, or laser/optical receiver/transmitter pairs that convert between electronic signals and optical signals (see FIG. 3).  
         [0073]    Chassis  12  may also include vertical transport channels  18  (illustrated symbolically in FIG. 1) for making electrical connections with adjacent vertically stacked modular electronics clusters. FIGS. 4 and 5 illustrate one implementation of vertical transport channels  18  using a connector and pin arrangement according to an embodiment of the present invention. Referring again to FIG. 1, chassis  12  may provide power, cooling, or hardware such as passive connectivity (e.g. wires, terminations, and the like) or active connectivity (e.g. amplifiers, line drivers, and the like) for resource cartridges  14 , in order to propagate electrical signals throughout chassis  12  and between adjacent clusters to additionally connected chassis, each with additional clusters.  
         [0074]    Embodiments of the present invention are scalable in that they include modular electronics clusters designed such that any number of modular electronics clusters may be connected to, and become a working part of, a larger electronic system, without the need for manual installation of additional electrical connection hardware such as connectors, connector adapters, wire bundles, cables, or the like. Preferred embodiments of the present invention are scalable in the vertical dimension and scalable in any horizontal direction. In further preferred embodiments, the resources in the electronic system communicate through a homogeneous topology heterogeneous (variant) protocol that expands as the electronic system expands, without the need to add communication circuitry beyond what is already contained in each modular electronics cluster. Embodiments of the present invention are also geometry-variant in that they are not limited to any particular shape.  
         [0075]    Cartridge-based embodiments of the present invention include electronic hardware adapted to be quickly and easily connectable to, and become a working part of, a larger electronic system without requiring access to the interior of the larger electronic system, and without the need for manual installation of additional electrical connection hardware such as connectors, connector adapters, wire bundles, cables, or the like. In preferred embodiments, resource cartridges include a housing, which protects sensitive electronic components from the elements and makes the resource cartridges easier to handle with less chance of damage. Although FIG. 1 illustrates an embodiment where only one resource cartridge  14  fits into each slot of chassis  12 , in alternative embodiments a plurality of resource cartridges  14  may fit into each slot of chassis  12 .  
         [0076]    An alternative embodiment of the present invention is illustrated in FIG. 6, which is similar to the embodiment of FIG. 1, but further includes a centralized data transport unit  16  insertable into or removable from chassis  12 . The data transport unit  16  is a passive or active device that routes signals along a particular path, either through hardware such as fixed electrical paths, or through configurable electrical paths. Again, it should be understood that the hexagonal shape of the embodiment of FIG. 6 is merely exemplary, and that other geometries fall within the scope of embodiments of the present invention. In the embodiment of FIG. 6, data transport unit  16  is insertable into chassis  12  through openings in the top, bottom, or sides (cartridge openings) of chassis  12 . In a preferred embodiment, data transport unit  16  makes a direct electrical connection with the resource cartridges  14  through lateral transport channels (not shown in FIG. 6) within the interior of the chassis  12  using conventional pin and socket arrangements, phototransistor/laser diode pairs, or the like, and the chassis  12  just serves to retain the data transport unit  16  and resource cartridges  14 . In an alternative embodiment, data transport unit  16  makes a direct electrical connection with the chassis  12  through the lateral transport channels (not shown in FIG. 6). Data transport unit  16  may also include bi-directional vertical transport channels  18  on the top and bottom thereof for making electrical connections with adjacent stacked modular electronics clusters.  
         [0077]    Another alternative embodiment of the present invention is illustrated in FIG. 7, which is similar to the embodiment of FIG. 6, except that it does not include a chassis. In FIG. 7, the “receptacle” for the resource cartridges  14  is the data transport unit  16 . Again, it should be understood that the hexagonal shape of the embodiment of FIG. 7 is merely exemplary, and that other geometries fall within the scope of embodiments of the present invention. In the embodiment of FIG. 7, resource cartridges  14  connect directly to data transport unit  16  through lateral transport connectors  60  containing lateral transport channels. Electrical connectivity within lateral transport connectors  60  may be effected by conventional pin and socket arrangements, phototransistor/laser diode pairs, or the like. Data transport unit  16  may also include bi-directional vertical transport channels  18  for making electrical connections with adjacent (upper and lower) stacked modular electronics clusters.  
         [0078]    The vertical cascadability, or scalability, of embodiments of the present invention can be illustrated symbolically in a series of drawings beginning with FIG. 8, which shows a basic six-node modular electronics cluster. In FIG. 8, the six resource cartridges  14  and data transport unit  16  of FIG. 6 are symbolically represented as six spheres surrounding and connected to a central sphere. FIG. 9 shows the same six-node modular electronics cluster contained within a chassis  12 , symbolically represented as a hexagonal enclosure. A stack of six modular electronics clusters can be connected through their centralized data transport units  16  for greater computing power, as illustrated in FIG. 10. In FIG. 10, each modular electronics cluster is electrically connected to adjacent modular electronics clusters through vertical transport channels in the data transport unit  16  (the central sphere). FIG. 11 illustrates a vertical stack of six modular electronics clusters  10  of the type illustrated in FIG. 6, each modular electronics cluster  10  connected to an adjacent modular electronics cluster  10  through vertical transport channels  18 . It should be understood that the stacking and connection concepts of FIG. 11 are equally applicable to modular electronics clusters  10  of the type illustrated in FIG. 1 or  7 .  
         [0079]    Another alternative embodiment of the present invention is illustrated in FIG. 12, wherein the hexagonal unit is not a chassis, but an individual resource cartridge  14 . In the embodiment of FIG. 12, each resource cartridge  14  may contain a cluster of resources (not shown in FIG. 12) which are connected to each other internally, and are capable of connecting to other resources in adjacent clusters through vertical transport channels  18  and lateral transport channels  24 . The vertical transport channels  18  allow multiple resource cartridges  14  to be stacked and electrically connected without need for a chassis or a separate data transport unit, as illustrated in FIG. 13. Alternatively, a chassis could be added to provide some structural support while maintaining electrical connectivity within and between the resource cartridges  14 . Note that in FIGS. 12 and 13, a base module  20 , which may contain power supplies, additional disk drives, and the like, supports and is electrically connected to the plurality of resource cartridges  14 . Again, it should be understood that the hexagonal shape of resource cartridge  14  in FIGS.  12  and  13  is merely exemplary, and that other geometries fall within the scope of embodiments of the present invention. The lateral transport channels  24  allow horizontally adjacent resource cartridges  14  to be connected, providing the horizontal or lateral scalability illustrated in FIG. 14. Electrical connectivity between horizontally adjacent resource cartridges  14  may be effected by conventional pin and socket arrangements, phototransistor/laser diode pairs, or the like.  
         [0080]    [0080]FIG. 15 illustrates an example of a further alternative embodiment, wherein three stacks of multiple resource cartridges  14  are contained in a chassis  12 . Chassis  12  includes a base module  20  and vertical extensions  62 . Resource cartridges  14  are electrically connectable to vertical extensions  62  of chassis  12 , and to adjacent resource cartridges  14 , through lateral transport channels  24 .  
         [0081]    As noted briefly in embodiments of the present invention described above, electrical connectivity may be needed between one or more of resources or resource cartridges, chassis, and data transport units. It should be understood that any of the conventional serial or parallel data transmission schemes, which include, but are not limited to wires, terminations, twisted pairs, shielded wires, controlled impedance wiring or lines, fiber optics, line drivers and receivers, photo transistors, and laser diodes fall within the scope of embodiments of the present invention.  
         [0082]    Yet another embodiment of the present invention is illustrated in FIG. 16, wherein chassis  12  of modular electronics cluster  10  is rectangular-shaped, and resource cartridges  14  plug into slots in the front of chassis  12 . A data transport unit (not shown in FIG. 16) located within chassis  12  may include vertical transport channels  18  positioned at the top and bottom of chassis  12  to connect with adjacent vertically-stacked modular electronics clusters, and/or horizontal transport channels  38  to connect with adjacent horizontally-aligned modular electronics clusters  10 . Lateral transport channels  24  (not shown in FIG. 16) connect the resource cartridges  14  to the data transport unit.  
         [0083]    Although the resource cartridges  14  and data transport unit of modular electronics cluster  10  of the embodiments of the present invention illustrated in FIG. 16 may resemble the circuit card and backplane architecture of a conventional personal computer (PC), the embodiment illustrated in FIG. 16 is unlike a PC or other computing device with a similar internal architecture for several reasons. First, conventional PCs typically include a chassis cover that must be removed to insert or remove circuit cards. Second, in a PC-based system there are a limited number of slots, and once the slots are filled, additional computers or racks and wiring must be added to effect an expansion of the system. In contrast, in the embodiment of FIG. 16, any number of resource cartridges  14  can be inserted into any number of stacked or horizontally aligned modular electronics clusters without the need for additional hard wiring. The data transport unit, with its vertical transport channels  18  and horizontal transport channels  38  electrically connectable to adjacent modular electronics clusters, functions as an expandable backplane.  
         [0084]    Regardless of how resources are physically scaled, the scalability achievable by embodiments of the present invention may be enabled by connecting all resources through a homogeneous topology heterogeneous (variant) protocol. Unlike simple scalable systems that can interconnect basic elements such as resistors or capacitors using direct point-to-point wiring, embodiments of the present invention may include complex standalone systems within each resource, the interconnection of which requires a centralized switch fabric distributed across all resources in a system. When multiple resources are connected together, the interconnected homogeneous topology heterogeneous (variant) protocol forms an integrated network enabling communication between any resource in the system. Through the centralized switch fabric, all resources in the network are essentially connected together.  
         [0085]    Communication paths between resources within a cluster, and between resources in adjacent clusters, may be implemented as symbolically illustrated in the example of FIG. 17, which shows a stack of two clusters  88  and the connectivity of their resources  90 . Vertical transport channels  18  are indicated by dashed lines, while lateral transport channels  24  and  98  are indicated by solid lines. Note that lateral transport channels  24  connect resources  90  within the same clusters, while lateral transport channels  98  connect resources in adjacent vertical stacks. It should be understood, however, that the connectivity symbolized by lateral transport channels  98  can be accomplished by utilizing the topmost and bottommost vertical transport channels  18  and connecting resources  94  in adjacent vertical stacks in a loop indicated by paths  96 . FIG. 18 symbolically illustrates some of the connectivity paths that may be required by each resource  90 . Bridge circuitry may be employed to provide high-bandwidth, low-latency messaging and transparent input/output (I/O) transfers between the buses of each resource  90 . For example, Peripheral Component Interconnect (PCI)-standard compliant and Scalable Coherent Interface (SCI)-standard compliant bridge chips, such as the Dolphin Interconnect Solutions PSB-64 Bridge Chip with 64-bit buses and remote memory access (RMA), may be used to provide an SCI-compliant link for each resource cartridge  14 . FIG. 19 symbolically illustrates how two PSB-64 Bridge Chips  86  can be implemented to provide connectivity for a resource  90 . Lateral transport channel  98  does not appear in FIG. 19 because, as indicated above with reference to FIG. 17, the connectivity of lateral transport channel  98  can be accomplished using vertical transport channels  18 . Thus, the use of two Dolphin PSB-64 Bridge Chips for each of the resource cartridges  14  in FIG. 17 allows any resource to communicate with any other resource through a scalable, single-protocol integrated homogeneous communication network.  
         [0086]    A perspective view of a preferred embodiment of the invention is shown in FIG. 20. FIG. 20 illustrates six hexagonal modular electronics clusters  10  in a vertical stack, each modular electronics cluster  10  coupled to adjacent modular electronics clusters  10  through its data transport unit  16 . Within each modular electronics cluster  10  is a chassis  12  which holds a plurality of resource cartridges  14  in each hexagonal face of chassis  12 . The arrangement is vertically scalable so that it can accommodate additional modular electronics clusters  10  simply by stacking them. In preferred embodiments, underneath the vertical stack is a base module  20  which is electrically connected to the vertical stack, and may contain power supplies, additional disk drives, and the like. In further preferred embodiments, below base module  20  is a floor module  22 , which may also be electrically connected to the base module  20  and contain additional electronics and hardware for connecting to adjacent floor modules.  
         [0087]    [0087]FIG. 21 illustrates a plurality of vertical stacks  70  of modular electronics clusters  10 , each vertical stack connected to other vertical stacks through floor modules  22 . In preferred embodiments, each resource cartridge  14  in FIG. 21 is capable of communicating with every other resource cartridge  14 . First, resource cartridges  14  in each cluster  10  are electrically connected to each other by the data transport unit  16  within that cluster. Second, each data transport unit  16  electrically connects any given resource cartridge  14  in any given cluster to any other resource cartridges  14  in any other cluster in the same vertical stack  70 . Finally, any given resource cartridge  14  in any given vertical stack is electrically connectable to any other resource cartridges  14  in any other vertical stack  70  through electrical connectivity provided in the data transport units, base modules  20 , and floor modules  22 .  
         [0088]    A comparison of horizontal or lateral scalability between various embodiments of the present invention may be made with reference to FIGS. 22 and 23. In FIG. 22, a vertical stack of resource cartridges  14  (see the embodiment of FIG. 12) is laterally scalable by placing other vertical stacks of resource cartridges in close proximity and connecting the lateral transport channels  24  of adjacent resource cartridges, as indicated by arrow  84  (see FIG. 14). In contrast, in FIG. 23, a vertical stack  70  of modular electronics clusters  10  (see the embodiment of FIG. 6), including resource cartridges  14 , is laterally scalable to modular electronics clusters  10  in other vertical stacks  70  through lateral transport channels that connect adjacent resource cartridges  14  through the data transport unit  16 , base modules (not shown in FIG. 23), and floor modules (not shown in FIG. 23), as indicated by arrow  86  (see FIG. 21). In this manner, lateral scalability is achieved even though the vertical stacks may be physically separated.  
         [0089]    [0089]FIG. 24 illustrates both the vertical and horizontal scalability of resources according to embodiments of the present invention. In FIG. 24, a resource cartridge  14  containing a resource  90  forms part of a cluster  10 , which is part of a vertical stack  70 . It should be noted, however, that resource  90  need not be contained in a cartridge  90 , and in alternative embodiments may permanently reside within cluster  10 . Resource  90  communicates with bridge chips  86 , where signals can be propagated through lateral transport channels  24  to other bridge chips for communicating with other resources within the same cluster  10 , or propagated through vertical transport channels  18  to other bridge chips for communicating with other resources within vertically adjacent clusters, enabling vertical scalability. Furthermore, signals can be propagated through lateral transport channels  92  to other bridge chips for communicating with other resources within other stacks, enabling horizontal scalability.  
         [0090]    In preferred embodiments of the present invention, although the geometry of the modular electronics cluster is not limited to any particular configuration, each modular electronics cluster in a particular system will be “regular,” or the same geometry. Regular geometry-variant modular electronics clusters enable lateral or horizontal scalability in any direction. Thus, as is evident from FIG. 14 or  21 , in preferred embodiments hexagonal resource cartridges  14  (FIG. 14) or modular electronics clusters  10  (FIG. 21) allow for scalability in any horizontal direction.  
         [0091]    However, in alternative embodiments of the present invention, scalability in multiple horizontal directions is possible using other regular geometries having lateral transport channels on all sides. For example, FIG. 25 is a top-view symbolic illustration of a triangular cluster  10   b  that is scalable in all lateral directions. Triangular cluster  10   b  may represent a resource cartridge (see reference character  14  in FIG. 12) containing a cluster of resources, in which case the connections between adjacent triangular clusters  10   b  in FIG. 25 represent direct connections (see FIG. 22). Alternatively, cluster  10   b  may represent a modular electronics cluster having three resource cartridges, in which case the connections between adjacent triangular clusters  10   b  in FIG. 25 represent connections “through the floor” (see FIG. 23). Similarly, FIG. 26 is a top-view symbolic illustration of a square cluster  10   c  that is scalable in all lateral directions, and FIG. 27 is a top-view symbolic illustration of a hexagonal cluster  10   d  that is scalable in all lateral directions. Although some shapes (such as a pentagonal shape) do not yield optimal compactness when laterally scaled, any multi-sided modular electronics cluster  10  that accommodates multiple resource cartridges falls within the scope of embodiments of the present invention. It should be understood that as the number of sides increases, the shape of the modular electronics cluster approaches and includes a circle, as illustrated in FIG. 28.  
         [0092]    The scalability inherent in embodiments of the present invention results in more than increased processing power. Scalability also provides insulation from obsolescence, because resource cartridges can be swapped out and systems with increased processing capabilities can be created by using next-generation resource cartridges. Furthermore, the scalability of modular electronics clusters  10  enables maximum processing power in a minimal space. For example, a conventional parallel computing system with the processing power of the system of FIG. 21 may take up several rooms with associated space penalties, cooling requirements, and maintenance overhead. In addition, such a conventional parallel computing system may include a significant amount of redundant components such as keyboards, keyboard controllers, video circuits, and the like, which may consume expensive “real estate” on the motherboard.  
         [0093]    However, because embodiments of the present invention allow for special-purpose resource cartridges to be plugged in on an as-needed basis, much of the hardware in a typical desktop computer that would be unnecessary in a parallel computing system can be eliminated. As these unnecessary components represent a significant portion of the cost of a PC, the performance per dollar ratio and the performance per volume ratio can be improved. In addition, improvements in compactness provide a secondary benefit of cost savings in overhead and maintenance.  
         [0094]    In cascaded computing systems formed from modular electronics clusters  10 , a resource task manager may be used to control parallel processing. This resource task manager can be centralized in one server located within the resource cartridges, or it could be distributed among many servers. Distributed run-time diagnostics may be continually performed in the form of pinging or other communications between the resource task manager and the other distributed processors, to determine what processors are available over the system. Thus, in one embodiment of the present invention a diagnostic link port may be added to every resource cartridge connector to communicate to the resource task manager that a new processor has been added to the system, or that an existing processor has now failed.  
         [0095]    Note that although the above description and figures of cartridge-based geometry-variant scalable electronics covered modular electronics clusters with identical-geometry cartridges, it should be understood that cartridges of different sizes may be employed within a single chassis by having different sized openings. Alternatively, fractional-height cartridges may be designed to be received into full-height chassis openings.  
       Cascadable Floor Modules for Scalable Electronics  
       [0096]    As described above, FIG. 20 illustrates six hexagonal modular electronics clusters  10  in a vertical stack. The arrangement is vertically scalable so that it can hold additional modular electronics clusters  10  simply by stacking them. Underneath the vertical stack is a base module  20 , which electrically connects the vertical stack to a floor module  22 . Floor module  22  may contain additional electronics and hardware for connecting to adjacent floor modules  22 . As illustrated in FIG. 21, in preferred embodiments of the present invention floor module  22  includes a top surface  76  supported by support structure  78 . An interior volume  80  is defined below top surface  76 .  
         [0097]    In preferred embodiments, vertical transport channels  82  are located on top surface  76 , and provide connectivity through base module  20  to the vertical stack of modular electronics clusters. In addition, lateral transport channels  84  located on one or more sides of the floor module  22  connect to vertical transport channels  82  and provide connectivity between floor modules  22 .  
         [0098]    When abutted against other floor modules  22  (see FIG. 21), the floor modules  22  create floor space and a physical separation between adjacent vertical stacks  70  of modular electronics clusters, enabling easier access to the vertical stacks of modular electronics clusters. Access to lateral transport channels and other hardware for connecting adjacent floor modules  22  may be provided through access panels  40  (see FIG. 20) in the top surface of floor module  22 . Thus, after floor modules  22  are aligned in close proximity to each other, connections between the lateral transport channels of adjacent floor modules  22  may be completed by opening adjacent access panels  40  and physically making the required connections. In other embodiments, the connections are made automatically as the floor modules  22  are aligned in close proximity. In the embodiment of FIGS. 20 and 21, floor module  22  is hexagonally shaped. However, it should be understood that in alternative embodiments, floor module  22  may include any multiple-sided shape. Furthermore, it should be understood that any scalable electronics system may be supported on floor modules  22  and scaled by laterally arranging the floor modules  22  as illustrated in FIG. 21.  
         [0099]    In alternative embodiments of the present invention, the floor modules are designed to accept either a base module  20  or a flush-mount cover  72  (see FIG. 21). With the base module  20  installed, a vertical stack  70  of modular electronics clusters can be added. With the flush-mount cover  72  installed, the vertical transport channels  82  are covered and protected, and the floor module  22  may be used as a “blank” or placeholder module (see reference character  74 ) to create additional space between vertical stacks  70  of modular electronics clusters, while still providing interconnectivity for other vertical stacks  70  of modular electronics clusters.  
       Hybrid-Geometry Resource Cartridge  
       [0100]    As noted above, FIG. 7 illustrates an example of a modular electronics cluster  10  in which resource cartridges  14  connect directly to data transport unit  16 . Electrical connectivity between data transport unit  16  and resource cartridges  14  may be effected by conventional pin and socket arrangements, phototransistor/laser diode pairs, or the like. (See connectivity illustrated in FIGS. 2 and 3.) Data transport unit  16  may also include vertical transport channels  18  for making electrical connections with adjacent stacked modular electronics clusters  10 .  
         [0101]    Fundamentally, the embodiment illustrated in FIG. 7 represents the conversion of one shape (rectangular resource cartridges  14 ) into another shape (the hexagonal arrangement of rectangular resource cartridges  14 ). The rectangular shape of resource cartridges  14  may be dictated by the shape of circuit boards, integrated circuits, or the like contained within resource cartridge  14 . It would be desirable to orient these rectangular resource cartridges  14  into a hexagonal shape to take advantage of the compactness and efficiency in scaling that are afforded by hexagonal shapes. However, the empty spaces  68  shown in FIG. 7 demonstrate that the rectangular shapes of resource cartridges  14  do not allow for a fully compact modular electronics cluster  10 .  
         [0102]    To improve compactness and minimize empty spaces  68  (FIG. 7) in the horizontal dimension while maintaining the rectangular shape of the resource cartridges, resource cartridges may be overlapped by placing alternating resource cartridges in two different planes, as illustrated in the top view of FIG. 29. In FIG. 29, lower resource cartridges  42  lie in a lower plane, while upper resource cartridges  44  lie in an upper plane. However, although the arrangement of FIG. 29 produces a narrower gap  68   a , gaps  46  are present between upper resource cartridges  44 , and between lower resource cartridges  42 . In addition, the arrangement increases the overall vertical size of the cluster  10 .  
         [0103]    [0103]FIG. 30 illustrates a preferred hybrid-geometry resource cartridge embodiment  28  that minimizes both empty spaces and gaps. Hybrid-geometry resource cartridge  28  maintains the rectangular shape that may be required by existing, off-the-shelf components, as indicated by the portion of the cartridge identified by reference character  30 , and adds a multi-sided extension  32 . This multi-sided extension  32  fills in the gaps  46  left by the arrangement of FIG. 29, and allows for additional components to be placed within hybrid-geometry resource cartridge  28 . Furthermore, by alternating the orientation of adjacent hybrid-geometry resource cartridges  28  as illustrated in FIG. 31, improved compactness can be achieved with minimal empty space  68   c.    
         [0104]    In the embodiment of FIG. 30, hybrid-geometry resource cartridge  28  may comprise a unitary housing, or separate couplable housings  30  and  32 . Furthermore, in alternative embodiments one or more slots  36  shown on the outward facing edge of hybrid-geometry cartridges may be employed to take advantage of the additional cooling that results from the additional surface area created by slots  36 .  
         [0105]    [0105]FIG. 32 illustrates six hybrid-geometry resource cartridges  28  connected to a data transport unit  16  to form a single hybrid-geometry resource cartridge-based modular electronics cluster  34  according to a preferred embodiment of the present invention. It should be noted that each hybrid-geometry resource cartridge  28  is a single design, arranged in alternating orientations (i.e., flipped 180 degrees about axis A shown in FIG. 32). Furthermore, the hybrid-geometry resource cartridges  28  are arranged in a single plane, so that multiple hybrid-geometry resource cartridge-based modular electronics clusters  34  can be stacked and connected through their data transport units  16  as illustrated in FIG. 33.  
         [0106]    While the preferred embodiment of FIG. 30 is useful for adapting rectangular shaped resource cartridges to hexagonal modular electronics clusters, in alternative embodiments a variety of other hybrid geometries may be employed. In general, an adapter geometry (the multi-sided extension  32  in the example of FIG. 30) is used to convert a source geometry (the rectangular shape  30  in the example of FIG. 30), to a target geometry (the hexagonal shape of hybrid-geometry resource cartridge-based modular electronics cluster  34  in FIG. 32). In alternative embodiments of the present invention, as the source and target geometries vary, the adapter geometry will vary. Thus, embodiments of the present invention include resource cartridges of any shape that may be arranged in alternating orientations to form a more compact shape.  
         [0107]    Hybrid-geometry resource cartridges  28  according to embodiments of the present invention are applicable to modular electronics clusters comprised of: (1) cartridges  28  connected to data transport units  16 , as illustrated in FIG. 32, (2) cartridges  28  insertable into a chassis  12 , as illustrated in FIG. 34, or (3) data transport units  16  and cartridges  28  insertable into a chassis  12 , as illustrated in FIG. 35.  
         [0108]    Another alternative embodiment of the present invention is illustrated in FIG. 36, where the hybrid-geometry resource cartridges  28  are rectangular-shaped and connect to a data transport unit  16  without a chassis.  
         [0109]    Referring again to FIG. 32, when hybrid-geometry resource cartridges  28  are arranged in alternating orientations and connected to a central data transport unit  16 , it should be understood that the electrical connections may also be in alternating orientations, depending on the location of the lateral transport connectors  60  on the hybrid-geometry resource cartridges  28 . In preferred embodiments of the present invention illustrated in FIG. 37, the lateral transport connector  60  on hybrid-geometry resource cartridge  28  is offset from the vertical centerline of the cartridge and is positioned at a point marked  60   a  in FIG. 30. This offset connector location requires that data transport unit  16  have two lateral transport connector placements; an upper placement (see reference character  62 ) and a lower placement (see reference character  64 ). With two placements, a hybrid-geometry resource cartridge  28  must be coupled to a data transport unit  16  in an orientation dictated by the location of the lateral transport connector  60 .  
         [0110]    In alternative embodiments of the present invention, the lateral transport connector on hybrid-geometry resource cartridge is again offset, but, as illustrated symbolically in FIG. 38, a single lateral transport connector  60  on data transport unit  16  may be designed with two sets of duplicated pins, each set of pins being rotated  180  degrees from the other set. Each pair of duplicated pins in each lateral transport connector  60  is internally connected within data transport unit  16 , such that a hybrid-geometry resource cartridge may be inserted in either orientation and still make proper connection with one of the sets of connector pins. This arrangement makes the orientation of a hybrid-geometry resource cartridge independent of its position around data transport unit  16 . However, after the first hybrid-geometry resource cartridge is coupled to data transport unit  16 , the required orientation of all other hybrid-geometry resource cartridges becomes fixed.  
         [0111]    In further alternative embodiments of the present invention, the lateral transport connector on hybrid-geometry resource cartridge is not offset, but is located on the vertical centerline of the cartridge. This connector location requires that lateral transport connectors  60  on data transport unit  16  have one placement, but two pin orientations, as illustrated symbolically in FIG. 39. With two orientations, a hybrid-geometry resource cartridge must be coupled to a data transport unit in an orientation dictated by the lateral transport connector. Trapezoidal connector collars may be used to facilitate proper orientation.  
         [0112]    In still further alternative embodiments, the lateral transport connectors may be perfectly symmetrical to allow a hybrid-geometry resource cartridge in either orientation to plug into the connector. In such an embodiment, a reversal switch, bi-directional multiplexer, or the like located internal to either the hybrid-geometry resource cartridge or the chassis may be employed to ensure proper connectivity.  
         [0113]    It should be understood that although FIGS.  37 - 39  illustrate one lateral transport connector per data transport unit side, in alternative embodiments of the present invention previously discussed, multiple hybrid-geometry resource cartridges may be plugged into a single slot, and therefore in alternative embodiments multiple lateral transport connectors  60  may be located in a vertical arrangement on each side of the data transport unit  16 , as shown in FIG. 40.  
         [0114]    One advantage of hybrid-geometry resource cartridges is that the source geometry volume can be designed to initially contain existing, off-the shelf products, while providing a migration path to maximum potential by allowing for cartridges with off-the-shelf components to be replaced by next-generation cartridges containing state-of-the art components designed specifically to fit the entire volume of the cartridge. However, if existing, off-the-shelf components are not envisioned for use, which eliminates the constraint of adapting to a particular source geometry, in alternative embodiments of the present invention, multi-sided resource cartridges may be designed using only adapter geometries. As illustrated in the top view of FIG. 41, such multi-sided resource cartridges  18  are not constrained by existing products such as rectangular circuit boards, for example, but may be designed using components such as proprietary silicon and photonic switching elements arranged to fit the multi-sided shape. As illustrated in the example of FIG. 41, multi-sided resource cartridges  18  are coupled to a hexagonal data transport unit  16 , and shaped to achieve maximum volume with minimal overall compactness. In such embodiments, the alternating orientations of the previously discussed adjacent hybrid-geometry resource cartridges may not be necessary. Such cartridges would not overlap but would simply slide into the chassis adjacent to each other. It should also be noted that multi-sided resource cartridges with one or more curved sides also fall within the scope of the present invention.  
       Centralized Multi-Sided Volumetric Data Transport Unit  
       [0115]    In embodiments of the present invention described above, modular electronics clusters  10  are scalable when arranged and connected in an organized manner that allows them to fill three dimensional space, as illustrated in the example of FIG. 11. The scalability achievable by embodiments of the present invention is made possible by connecting all modular electronics clusters, and all resources within each modular electronics cluster, through a homogeneous topology heterogeneous (variant) protocol.  
         [0116]    This homogeneous topology heterogeneous (variant) protocol is distributed across all modular electronics clusters in a system. As described above, in embodiments of the present invention, modular electronics clusters may include a centralized data transport unit. An example of such a data transport unit  16  is illustrated in FIG. 6. Although data transport unit  16  in FIG. 6 is hexagonal-shaped, embodiments of the present invention include any multi-sided data transport unit  16 . The centralized location of the data transport unit in preferred embodiments of the present invention allows modular electronics clusters to be located around the data transport unit, thereby taking advantage of the compactness afforded by circles, or objects that approach a circular shape.  
         [0117]    Electrical connectivity between adjacent modular electronics clusters  10  is achieved through data transport units  16 , which contain a homogeneous topology heterogeneous (variant) protocol. In alternative embodiments, the electronic hardware necessary to implement this communication network may be located in the chassis or in the resource cartridges. When multiple modular electronics clusters are connected together, the interconnected homogeneous topology heterogeneous (variant) protocol forms an integrated network for enabling communication between resource cartridges within the same chassis or in different chassis. Examples of similar systems known in the art include telephone switching networks, Ethernet routers, and repeaters.  
         [0118]    In preferred embodiments of the present invention, electrical connectivity between adjacent resources  14  is achieved through vertical transport channels  18  and lateral transport channels  24 , illustrated symbolically in FIG. 17. Vertical transport channels  18  allow a resource  14  to be connected to vertically adjacent resources, while lateral transport channels  24  allow a resource  14  to be connected to laterally adjacent resources. As previously described, FIG. 24 illustrates another type of lateral transport channel  92  which is used to connect resources in adjacent vertical stacks. In preferred embodiments, vertical transport channels  18  and lateral transport channels  24  and  92  are propagated through data transport unit  16 . However, in alternative embodiments the bridge circuitry  86  used to provide a homogeneous topology heterogeneous (variant) protocol may be located either in the data transport unit  16 , chassis  12 , or resource cartridge  14 .  
         [0119]    In embodiments of the present invention, data transport unit  16  may be insertable into, or removable from, chassis  12  through openings in the top, bottom, or sides (cartridge openings) of chassis  12 . FIG. 42, which illustrates an example embodiment of hybrid-geometry resource cartridges  28  coupled to a hexagonal data transport unit  16  with the top of chassis  12  removed for clarity, is useful to describe the removal of a data transport unit  16  from the cartridge openings. As FIG. 42 illustrates, by removing two adjacent hybrid-geometry resource cartridges, data transport unit  16  can be slid out first in the direction indicated by arrow  52 , and then in the direction indicated either by arrows  54  or  56 , until it can be removed from cartridge openings  48  or  50 . In alternative embodiments, a portion of the chassis (indicated by dotted lines and reference character  58 ) may be removable to allow data transport unit  16  to be removed in the direction of arrow  52  only.  
         [0120]    To facilitate removal of data transport unit  16  in the direction of arrow  52  without first removing all hybrid-geometry resource cartridges  28 , lateral transport connectors  60  may comprise, in preferred embodiments, contactless phototransistor/laser diode pairs, or the like. In alternative embodiments, lateral transport connectors  60  may be retractable in one or more dimensions to break all physical connections and ready the data transport unit  16  for removal. If the connectors are implemented with simple pin and socket arrangements, each cartridge  28  needs to be removed slightly from the chassis so as to disconnect the pins from their respective sockets, and then the data transport unit  16  can be removed as indicated above.  
         [0121]    The advantage of side removal of data transport units can be understood with reference to FIG. 43 which illustrates an example embodiment of a vertical stack of three modular electronics clusters, each modular electronics cluster comprised of six hybrid-geometry resource cartridges  28  coupled to a hexagonal data transport unit  16  with the chassis removed for clarity. If the data transport unit  16  on the bottom or middle modular electronics cluster needs to be replaced, side removal will allow the data transport unit  16  to be swapped out without having to remove the uppermost modular electronics clusters.  
       Hexagonal Chassis For Housing and Volumetric Cascading of Electronics  
       [0122]    As described above, a number of embodiments of the present invention can be preferably implemented in a hexagonal shape. For example, FIG. 1 illustrates a modular electronics cluster  10  comprising a hexagonal chassis  12 , FIG. 32 illustrates six hybrid-geometry resource cartridges  28  connected to a hexagonal data transport unit  16 , FIG. 12 illustrates a hexagonal resource cartridge  14 , and FIG. 21 illustrates hexagonal floor modules  22 .  
         [0123]    Alex Thue, a Norwegian mathematician, has proven that hexagonal packing provides the greatest density in a two-dimensional plane. This proof is described in an article entitled “Cannonballs and Honeycombs” by Thomas C. Hales, Notice of the AMS, April 2000, Volume 47, Number 4, at p. 442. The efficiency of the hexagonal shape is demonstrated in spatial economic theory and is related to the maximum compactness of circles. For example, when implementing digital processing algorithms on two-dimensional images, if the pixels are arranged in hexagonal form, there is a 33% increase in the processing efficiency as opposed to rectangular pixels. This efficiency increase is due to the fact that hexagonal shapes can be arranged in a more compact array, and therefore it takes fewer pixels to implement the processing algorithms. Because hexagonal shapes can be arranged in a more compact array than other shapes, hexagonal implementations of embodiments of the present invention can produce increased packaging efficiency, shorter signal routing, and less signal degradation.