Abstract:
Network supervising apparatus for graphically distinguishing a path between two points on a network, and a method therefor, and computer program for carrying out the method, comprising: 
     a memory ( 21 ), in use, storing information relating to the components ( 12, 13, 14 ) of the network and the links ( 16 ) between those components; 
     a visual display apparatus ( 18 ) connectable with said memory and including processor apparatus ( 19 ) to convert the information in said memory into a visual display on said visual display apparatus representing the components of the network and the links between these components; 
     a manually operable selector ( 22 ) to select two components or links displayed on said visual display apparatus; 
     said signal processor apparatus processing the signals to said visual display apparatus to visually distinguish a set of components and/or links forming a link between the selected components or links and the other components and links.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to supervising a network, that is a network of electronic components comprising, for example, workstations, personal computers, servers, hubs, routers, bridges, switches, (hereinafter referred to as components of the network), and links between these components which may be in the form of physical cable or wireless links. The network may be a local area network (LAN), wide area network (WAN) or other types and may operate in accordance with any desired protocol. 
     After such a network has been installed, it is desirable for the person appointed network manager to be able to understand the technical operation of the network. In known network management systems, the manner in which the relevant data is retrieved from the managed devices, compiled and displayed has been problematic in several respects. Firstly, the data received from each of the managed devices is simply compiled and displayed as a list of data for the user to interpret. Secondly, the data does not provide information about unmanaged devices. Thirdly, information about a given network device, such as the type of device, location of the device on the network and operating speed of the device, may be contained in different sections of the compiled data. Consequently, conventional systems are cumbersome and difficult to use. 
     In co-pending UK patent applications numbers 9910844.1, 9910845.8, 9910838.3, 9910837.5, 9910839.1, 9910840.9 filed in the name of the assignee of the present applications and which are incorporated herein, we describe various arrangements for providing automatic interrogation of the network to thereby produce a network map which may be displayed on a visual display unit showing the components and links between the components. At its simplest, and where the component is a “managed” component, this is usually provided by interrogation using a known protocol, such as the SNMP protocol, of the so-called ‘agent’ of each component which stores the components unique MAC address, the type of component and the MAC addresses the components which are connected to the ports directly or indirectly. 
     It is desirable in this supervising capacity to be able to graphically distinguish a path between two points on a network. This is particularly useful in diagnosing problems, by tracing a path between two components. Whilst path tracing may be a relatively simple matter where there are relatively few components, in a complex network, the paths between two components will not be immediately obvious and indeed it is desirable to be able to ascertain whether there is more than one such path. 
     SUMMARY OF THE INVENTION 
     The present invention provides a network supervising apparatus comprising: 
     a memory, in use, storing information relating to the components of the network and the links between those components; 
     a visual display apparatus connectable with said memory and including signal processor apparatus to convert the information in said memory into a visual display on said visual display apparatus representing the components of the network and the links between these components; 
     a manually operable selector to select two components displayed on said visual display apparatus; 
     said processor apparatus processing the signals to said visual display apparatus to visually distinguish a set of components and/or links forming a path between the selected components and the other components and links. 
     The present invention also provides a method of supervising a network comprising: 
     converting information relating to the components of the network and the links between those components into a visual display on a visual display apparatus representing the physical relationship between the components of the network and the links between these components; 
     manually selecting two components displayed on said visual display apparatus; 
     processing the information to visually distinguish a set of components and/or links forming a path between the selected components and the other components and links. 
     The present invention also provides a computer program on a computer readable medium for use in supervising a network, said program comprising: 
     program means for accessing information relating to the components of the network and the links between those components; 
     program means for converting said information into a form to provide on a visual display apparatus, a visual display, representing the physical relationship between the components of the network and the links between these components; 
     program means actuated by a manually operable selector which selects two components displayed on said visual display apparatus, said program means causing said visual display apparatus to visually distinguish a set of components and/or links forming a path between the selected components and the other components and links. 
     The present invention also provides a computer program embodied in a carrier wave for use in supervising a network, said program comprising: 
     program means for accessing information relating to the components of the network and the links between those components; 
     program means for converting said information into a form to provide on a visual display apparatus, a visual display, representing the physical relationship between the components of the network and the links between these components; 
     program means actuated by a manually operable selector which selects two components displayed on said visual display apparatus, said program means causing said visual display apparatus to visually distinguish a set of components and/or links forming a path between the selected components and the other components and links. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Preferred embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which: 
     FIG. 1 is a diagrammatic view of a network incorporating a preferred embodiment of the invention, 
     FIG. 2 is a view of one display provided on a visual display apparatus of the network of FIG. 1, 
     FIG. 3 is a view of an alternative display to that shown in FIG. 2, and 
     FIG. 4 sets out the program steps in accordance with the preferred embodiment of the invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIG. 1 there is shown a network  10  comprising a plurality of components in the form of a network supervisor&#39;s workstation or computer  11 , other workstations  12 B-E, hubs  13 A,  13 B, and switch  14 . The network is a simple network and is set out for purposes of illustration only. Other configurations and arrangements, may be used. 
     The components are connected together by means of links  16 A-H which may be hard wired and utilise any desired protocol, and link  16 F which is a wireless link. 
     The network supervisor&#39;s workstation includes, in addition to a visual display unit  18 , a central processing unit or signal processor  19 , a selector which may be in the form of a mouse  22 , a program store  21  which may comprise, for example, a CD drive, a floppy disk drive or a zip drive, and a memory  17  (which may be local to the supervisor&#39;s workstation or elsewhere and accessible, for example, over the network) for storing a program which may have been loaded from the program store  21  or downloaded for example via Internet from a website. 
     FIGS. 2 and 3 show different visual displays which are displayed on the visual display unit  18  of the network supervisor. 
     By means which is disclosed in the co-pending patent applications referred to above, the network supervisor&#39;s computer  11  may interrogate and analyse the network, and store in the memory  17  the information relating to the components within the network and the links between the components. In essence, most quality components include a so-called agent which stores information about the component such as its unique MAC number, its ID which identifies what the component is and what model type it is, how many ports it has and how they are connected, and the address to which at least some of the ports are connected. The computer  11  interrogates the agents of each component. 
     The computer  11  may, on command from the selector  22 , process signals from the memory  17  by the signal processor  19  and provide on the visual display unit  18  a network map showing each of the components and the links therebetween. In the examples shown in FIGS. 2 and 3, the network is simple (note that the network displayed in FIG. 2 corresponds to the network shown in FIG. 1) but of course in many instances the network will be considerably more complex and it may be necessary to arrange that the visual display unit  18  only shows a simplified version or only part of the network at any one time. 
     In the normal mode, all of the components in the network map shown in FIG. 2 will be displayed in the same way, that is they will be emphasised to the same extent. 
     In carrying out the method of the present invention, it is desired by the supervisor to determine the paths between two particular components. In the example illustrated, it is desired to show the path between the computer  11  and workstation  12 E. In the present instance there is only a single path but it will be understood that in real situations the path may not be so readily apparent and indeed there may be multiple paths between two selected components. 
     Thus the network supervisor manually selects the workstations  11  and  12 E by moving a cursor under the control of the mouse  22  and clicking on to the displays of the two relevant workstations (or by manually entering the ID, identifiers of the two components via a keyboard). At this point, the signal processor  19  will act on the relevant signals and cause the visual display unit to visually distinguish the set of components and/or links (ie components  11 ,  13 A,  14 ,  13 B,  12 E) forming a path between the two selected components from the other component and links (ie excluding components  11 ,  13 A,  14 ,  13 B,  12 E). That visual distinction may be one of the following: 
     a) The set of components and/or links (ie components  11 ,  13 A,  14 ,  13 B,  12 E) may be highlighted by increasing the contrast in their images. 
     b) The other components and links (ie excluding components  11 ,  13 A,  14 ,  13 B,  12 E) may be dimmed by reducing the contrast in their images. (As shown in FIG. 2) 
     c) The colours of either the set, or the other components and links may be changed. 
     d) The other components and links may be removed from the display or map. 
     In the case of d), the set (ie components  11 ,  13 A,  14 ,  13 B,  12 E) of components and links which form the link between the two selected components may be arranged in a straight line either horizontally as shown in FIG. 3 or alternatively vertically. 
     In the arrangement of FIG. 2, all of the network components and links are still maintained in the same position as when the path was not being displayed, including those which do not form part of the path. 
     As set out above, in a more complex network, there may be more than one path between the two selected components and in this case, the mouse  22  may be suitably operated, for example, by clicking the cursor on a suitable icon on the screen, to select the second and subsequent paths successively. Alternatively, particularly where the selection is carried out not by mouse but by keyboard, there may be provided plural icons or an arrow arrangement so as to direct the successive views to show different selected paths. 
     We have described how the network may be supervised. The method of the invention may be carried out under the control of the network supervisor&#39;s workstation or computer and in particular by means of a program controlling the processor apparatus of that computer or elsewhere in the system. 
     The program for controlling the operation of the invention may be provided on a computer readable medium, such as a CD, or a floppy disk, or a zip drive disk carrying the program, or may be provided on a computer or computer memory carrying the website of, for example, the supplier of the network products. The program may be downloaded from whichever appropriate source to the memory  17  of the supervisor&#39;s workstation and used to control the processor to carry out the steps of the invention as described. Particularly in the case of downloading from a website, the program will be embodied in a carrier wave received, for example, on a telephone line or other cable or by wireless, eg infra-red link. 
     The program may include (see FIG.  4 ), 
     a program step or means ( 100 ) for interrogating the agents of each component, 
     a program step or means ( 101 ) for storing information relating to the components interrogated, 
     program step or program means ( 102 ) for accessing (from the memory) the information relating to the components of the network and the links between those components, 
     program step or means ( 103 ) for converting said information into a form to provide on the visual display apparatus a display representing the components of the network and the links between the components, 
     on selection by the mouse or its equivalent of two components (step  104 ), program means ( 105 ) causes said visual display apparatus to visually distinguish a set of components and/or links forming a path between the selected components and the other components and links. 
     Program steps ( 100 ) and ( 101 ) may be provided by another program. 
     In one arrangement, program step ( 105 ) may include the following steps: 
     (a) Ascertain all possible paths through the network from one of the selected components, 
     (b) Store those paths in which the second selected component appears, 
     (c) Compare these paths and save only the unique paths. 
     Thus, for example, referring to FIG. 1 where it is intended to find all possible paths between computer  11  and workstation  12 E all possible paths starting with computer  11  are listed below (a path is defined as starting with the first selected component (workstation  11 ) and terminating either when the path reaches the second selected component, or, when it reaches a “dead end” that is only one port is being used on a particular component): 
     (1)  11 - 13 - 12 A 
     (2)  11 - 13 - 12 B 
     (3)  11 - 13 - 14 - 13 B- 12 D 
     (4)  11 - 13 - 14 - 13 B- 12 E 
     (5)  11 - 13 - 14 - 13 B- 12 C 
     The path set out in line  4  above is a unique path between computer  11  and workstation  12 E. 
     In a more complex arrangement (for example, where there is provided another component  13 C between component  14  and workstation  12 E), then there will be an additional path as follows: 
     (6)  11 - 13 - 14 - 13 C- 12 E 
     This will provide a second path which may be illustrated on suitable operation of the mouse (step  106  of FIG.  4 ). 
     The invention is not restricted to the details of the foregoing example.