SYSTEM FOR DATA NETWORKING USING INTER-SUBNET ROUTERS

Abstract: A networking system and controller are disclosed that integrates various subnets to more effectively manage and control data communication. The system integrates the subnets into an overlaid backbone network which can connect different devices such as phone line network devices, power line network devices, radio frequency (RF) cordless devices, and devices clustered around internet protocols to distribute data efficiently and reliably over the subnets.

Description: System for data networking using inter-subnet routers Field of the Invention This invention relates to a system for data networks; more particularity, the invention relates to a networking architecture that integrates various subnets to more effectively manage and control data communication. Background of the Invention With an increase in the number of households and businesses having multi- digital consumer electronic (CE) equipment, there are greater demands for data networks that link two or more PCs and/or CE devices together. In its simplest form, data communication takes place between any two devices that are connected by some form of transmission medium. However, it is generally impracticable for such devices to be point-to-point connected. To connect all devices directed to each other would be expensive and bulky (in view of the number of connections required) for the home or business. Accordingly, multiple PCs and/or CE devices are generally connected via a network. Figure 1 shows a prior art communication network 10. The network 10 includes workstations 11, communication nodes 12 and a communication network 13. The workstations 11 may be computers, terminals, telephones, and other communication devices. Each of the workstations 11 attach to respective communication nodes 12 which are capable of transferring data between the workstations 11 via the communication network 13. The communication network 13 may be any conventional-type network such as switched (circuit- or packet-switched) and broadband (packet radio, satellite, bus-local and ring-local) networks. The communication nodes 12 use various communication protocols to allow for proper communication between the workstations 11 via the communication network 13. Essentially, the protocols define the set of rules governing the exchange of data between the two workstations 11. The key functions of the protocol relate to syntax, semantics and timing. The communication may be direct (point-to-point) or indirect (via intervening active agents, e.g., the Internet). In addition, devices are also known that function as bridge protocol data units between two portions of the communication network 13. Such devices, e.g., routers, are used in LANs to transfer data between two different communication media, e.g., wireless to/from wired. These devices include physical layer and link layer communication applications for each respective medium over which data is to be transferred. The routers may be used as the communication node 12 to interface a LAN (e.g., the communication network 13) and an automated appliance (e.g., the workstations 11 which may have an infrared interface). Furthermore, systems are also known that communication commands to remote devices via electric power lines (e.g., intra-building or inter-building). In such systems, message signals are modulated on power signals. Interface nodes, coupling the remote device and the electric power lines, decode the commands. One of the major functions of a home/business network is to distribute data throughout the building or region. This type of data networking concept allows multiple users to perform various useful tasks. For example, these tasks include: internet-access sharing, with appropriate gateway applications, one PC can provide access to the Internet for an entire household, which eliminates the need for separate modems Internet accounts and phone lines; folder and hard disk sharing, which makes backup and file transfers easier; peripheral/appliances sharing, i.e., printers and facsimile machines; and audio and video entertainment, e.g., children at different locations within the home or in the neighborhood can play games or watch a video program simultaneously over the network. Another function for such home/business networks relates to smart systems (e.g., home automation) which allows for control of various home/business functions. The popularity of smart energy modules (which control the building environment) and intelligent security systems are increasing. Similar to routers, interfaces are known that connect such smart systems together and account for different communication parameters. The interface acts like a connection point (i.e., a switching node) for the various smart systems. The conventional market for home/business networking is mainly PC-centric, e.g., PCs connected via a local area network (LAN). Using existing infrastructure and technologies, one can connect devices by various means, e.g., coaxial cable, plastic optical fiber (pof), power line, phone line, integrated service digital network (ISDN), or wireless (IR and RF). Coaxial cable and plastic optical fiber can provide reliable 10/100 Mbps Ethernet and 100Mbps 1394b connections. Other mediums such as phone lines, power lines and wireless can generally provide low to medium data-rate connections. Of course, the selection of medium depends highly on whether there is a need for intra-room or inter-room connection. For devices in the same room, it is desirable to use cable and pof in order to have reliable and high bandwidth connection. However, for devices in different rooms or on different floors, one will have to drill holes and snake cables/fiber through walls. This is definitely not a preferred solution for many consumers because of the installation costs and disruption in the home. One way to cope with this problem is to use wires that are already in place or to use a wireless solution. The Home Phoneline Networking Alliance (HomePNA) has recently passed a standard for home networking using the phone lines. The first specification will provide data- rates up to 1Mbps but subsequent releases will go up to 10Mbps. In this standard, the networking protocol operates over phone lines existing within the building without interfering with regular voice communication. This is accomplished by using frequencies outside the range of human- voice communication. These frequencies are also compatible with ISDN services. Another approach is to make use of the power lines, as discussed above, that have the advantage of multiple power outlets located throughout the whole house. Currently, the maximum data-rate over power lines is about 350Kbps. Yet, other technologies include the use of a radio-based wireless network or a wired Ethernet network. Narious standards for indoor radio networks have been proposed in the U.S., Europe and Japan. In connection with the present invention, it is foreseen that other wireless networking products may also become popular in the market that include Bluetooth (<lMbps), HomeRF (~2Mbps), IEEE802.1 la and ETSI/BRAΝ (~36Mbps). Although radio-based technology can avoid wiring-related shortcomings, such technology, however, also has weaknesses related to interference (from other radio-based sources) and reliability. One major shortcoming related to the conventional home networks discussed above is that they rely on a single medium or technology for communication and interconnection. Moreover, in some cases, there may be multiple networks within a single building or residence. These multiple networks may essentially compete for the same bandwidth, e.g., radio frequencies. Even in the case where the multiple networks do not compete for the same bandwidth, there exists no integrated system for effectively managing and controlling such home/business network mediums. There thus exists in the art a need for improved systems for implementing and controlling home/business networks. Summary of the Invention The increase in digital consumer appliances will drive the networking market to new areas. It is foreseen that inter-room connections, multiple networking techniques are needed that will complementary each other. The infrastructure of a home, building (assuming no new wiring is to be installed) and proximate geographic regions will be composed of multiple subnets, e.g., a phone line subnet, a power line subnet and/or a wireless subnet. The present invention provides a network architecture that integrates the such subnets into an overlaid backbone network which can connect phone line network devices, power line network devices, radio frequency (RF) cordless devices, and devices clustered around internet protocols (IP), universal serial buses (USB) and PI 394, and distribute data efficiently and reliably over the subnets. One aspect of the present invention is directed to an inter-subnet router. The inter-subnet router transfers data to a destination-router via one or more subnets defined in a routing data structure. One embodiment of the invention relates to a controller including a plurality of data connections for a plurality of subnets, a plurality of input/output connections for a plurality of data devices, means for integrating one or more of the plurality of subnets and means for distributing data from one of the plurality of data devices to another of the plurality of data devices through the integrated subnets. Another embodiments of the invention relate to a data networking system and method including a plurality of integrated controllers to which respective data devices are coupled. These and other embodiments and aspects of the present invention are exemplified in the following detailed disclosure. Brief Description of Drawings The features and advantages of the present invention can be understood by reference to the detailed description of the preferred embodiments set forth below taken with the drawings, in which: Fig. 1 is a schematic block diagram of a prior art communication network; Fig. 2 is a schematic block diagram of a preferred embodiment; Fig. 3 is a schematic block diagram of another embodiment. Detailed Description Figure 2 illustrates a preferred embodiment of the present invention relating to the use of inter-subnet routers, i.e., controllers, for a home network 100. Of course, it should be understood that the invention is not limited to home networks. The invention may also be applied to any environment that benefits from data networking such as business and educational facilities. hi this example, a residence 200 including a bedroom 201, a living room 202, and a study 203 is shown. Each room has a respective inter-subnet router 101 that connects various devices in the room to at least one of a plurality of subnets. This example includes a phone line subnet 102, a power line subnet 103, a wireless subnet 104, a coaxial subnet 105, a fiber subnet 106 and an external network 107. Each room also include various end-user devices (e.g., TV 110, video recorder 111, laptop 112, phone 113, NCR 114, facsimile 115, printer 116 and personal computer 117) which may transmit and/or receive data over the various subnets. The routers 101 may be connect to all or some of the subnets. For example, the living room router 101 connects to all five subnets, but the study router 101 connects to all but the coaxial subnet 105. Alternatively, all of the end-user deceives at this location may be coupled to a single router 101. In this embodiment, the single router 101 then manages communication between the end-user devices and external devices located in a different building or location that also have access to the various subnets via an inter-subnet router. Each router 101 maintains data related to connectivity, available bandwidth and end-user devices connected thereto. For example, each router 101 may include tables as shown below, i.e., a connectivity table, a bandwidth availability table and a device table. The connectivity table provides information on the availability of the subnets. In operation, the connectivity table is automatically setup when the router 101 is associated with one or more subnets. The bandwidth availability table provides information on the reliability of the subnet 101 and the bandwidth available in each subnet 101. In operation, the bandwidth table is updated when a connection between two routers 101 is setup, released, or modified. The device table provides information on what end-user devices are connected to each router as well as the traffic requirement of each device, including the reliability and bandwidth requirements. For simplicity of illustration, mean bandwidth is used; however, in practice, other parameters such as peak and minimum bandwidth may be used as well. With the assistance of conventional signaling protocol, these three tables are used by a resource allocation scheme and a connection admission control policy, h this embodiment, the connectivity and bandwidth tables are used allocate subnet resources and facilitate connection admission control as discussed in more detail below. Table 1 : Connectivity table hi the connectivity table, the following notational conventions are used: ph - phone line subnet 102; pwr - power line subnet 103; wl - wireless subnet; cox - coaxial subnet 105; and fib - fiber subnet 106. As shown in the connectivity table above, the connection (or communication) paths from and to each router 101 via the various subnets is provided. From such a table, one can easily derive the subnets that are available at a particular router 101. Of course, it will be appreciated by one skilled in the art that other data structures can be defined to store and administer the connection data. The invention is not limited to a matrix-like table. In addition, each router 101 is not required to maintain such connectivity and bandwidth availability data. One of the routers 101 may store such information. The other routers 101 access the information as needed. In another embodiment, such information may be stored in an external device (e.g., a local or remote PC). The routers 101 then access the information from the external device as needed. Table 2: Bandwidth availability table In the Bandwidth availability table, the following notational conventions are used: phjotal represents the total bandwidth available for the phone line subnet, similar notational convention represent the total power the remaining subnets; "a" through "e" respectively represent the amount of bandwidth used within respective subnets at any particular time. The values of a through e are updated as bandwidth within a particular subnet is allocated or released. The available bandwidth at any moment in time can be easily calculated by subtracting the bandwidth used in a particular subnet from the total available bandwidth within the subnet. Table 2 also contains information relating to the reliability of each the subnets 102 through 106. Each of these subnets is rated based on accepted performance criteria or standards. Some subnets are inherently more reliable to use then others. Table 3: Device table An example of connection admission control policy is described as follow. When an end-user device (e.g., VCR 114 in the living room 202) wants to connect to another device (e.g., TV 110 in the bedroom 201), a connection setup message is generated from that device or its attached router 101 (i.e., the source router). This message is based on information in Table 3 (device table) and has the following format: Connection _setup. request (Source _Device, SinkJDevice, Traffic _descriptor) Wherein: Source _Device = Router _LR->D VCR, SinkJDevice = Router _BR->TV2, Traffic _descriptor = (required reliability, required bandwidth) and wherein: required reliability = max(D_R_DVCR, D_R_TV2) and required bandwidth = max(D_B_D VCR,D_B_TV2) n this example, the required reliability will be "high" and if BW_TV2 < BW_DNCR, then the required bandwidth will be "BW_DNCR". Upon receiving this connection setup message, the source router (Router_LR) determines whether there is any direct connection to the destination router, i.e., the sink router (Router BR) or not based on Table 1 (Connectivity table), hi this example, (ph,pwr,wl,cox) are available. However, if there is no direct connection, the source router will seek an indirect path via some other router to the sink router. As shown in Fig. 5, router 101B can connect to router 101C through router 101 A. In this case, the router 101B uses the fiber subnet 106 and/or power line subnet 103 to connect to the router 101 A. The router 101 A then uses the coaxial subnet 105 to connect to router 101C. If no connection can be made, a connection_setup.confirm (error: no available path) is returned. Since there are four possible subnets connecting RouterJ R and Router_BR, Router_LR will determine which subnet to use based on the traffic_descriptor parameters in the connection setup request message. Since the required reliability is "high", subnet "wl" will not fulfill the requirement. This leaves three other subnets (ph,pwr,cox) that meet the reliability requirement. The selection then starts with the phoneline subnet 102 and checks the request bandwidth against its available bandwidth. If the bandwidth requirement is fulfilled, a notification message will be sent to the sink device TV 110 and a confirmation message will be sent back to the source device NCR 114. However, if it is not fulfilled, the process will repeat for the powerline subnet 102 and so forth for the coaxial subnet 105. If no single subnet fulfills the bandwidth requirement, a combination of subnets will be used. When the bandwidth requirement is fulfilled, a confirmation message connection_setup.confirm(okay) is returned and the corresponding routers will update their tables. Otherwise, a negative confirmation message will be issued. While the present invention has been described above in terms of specific embodiments, it is to be understood that the invention is not intended to be confined or limited to the embodiments disclosed herein. On the contrary, the present invention is intended to cover various structures and modifications thereof included within the spirit and scope of the appended claims.

Claims: CLAIMS: 1. A data networking system comprising: a plurality of controllers; at least one data device coupled to each of the plurality of controllers; a plurality of subnets coupled to the plurality of controllers, each of the plurality of subnets including a predetermined amount of bandwidth; and means for integrating the plurality of subnets to distribute data. 2. The system according to Claim 1 , wherein the data is distributed using at least two of the plurality of subnets may be sent over the at least two subnets in a simultaneous manner. 3. The system according to Claim 1, wherein the at least one data device includes one or more of the following a computer, a display device, a video device, a consumer electronic device and a voice communication device. 4. The system according to Claim 1 , wherein the plurality of controllers have access to subnet connectivity data, subnet available bandwidth data and reliability data. 5 The system according to Claim 4, wherein the subnet connectivity data and the subnet available bandwidth data is stored in each of the plurality of controllers. 6. A controller comprising: a plurality of data connections for a plurality of subnets; a plurality of input/output connections for a plurality of data devices; means for integrating one or more of the plurality of subnets; and means for distributing data from one of the plurality of data devices to another of the plurality of data devices through the integrated subnets. 7. The controller according to Claim 6, further comprising means for routing the data using a different one of the plurality of subnets to improve reliability. 8. The controller according to Claim 6 or 7, wherein the controller included connectivity and bandwidth availability data and or reliability data on the plurality of subnets. 9. The controller according to Claim 6, wherein the plurality of input/output connections include interfaces for one or more of the following a computer, a display device, a video device, a consumer electronic device and a voice communication device. 10. A method for call admission control in a data networking system including a plurality of controllers, each of the plurality of controller having at least one data device coupled to respective controllers, and each of the plurality of controllers being connected to a plurality of subnets having a predetermined amount of bandwidth, said method comprising the steps of: maintaining data related to an amount of bandwidth available from each of the plurality of subnets; integrating the amount of bandwidth available from two or more of the plurality of controllers; determining a route to transmit data between at least two data devices connected between two different controllers using the integrated bandwidth; transmitting the data using the integrated bandwidth.

Inventors: NGO CHIU Y, NGO, CHIU, Y.
Applicants: KONINKL PHILIPS ELECTRONICS NV, KONINKLIJKE PHILIPS ELECTRONICS N.V.
Application year: 2001
Main classification: H04L12
IPC codes: H04L12