Abstract:
A network interface card and system incorporating the interface card with hardware link failure detect circuitry and operating system compliant driver and GUI management software and system operator selectable delay, to provide soft fail-over transfer from the primary to a secondary network link port without data loss. The systems comprising the multi-port interface card according to the present invention provide a single network and redundant paths with optional conversion to different data medium, e.g. between fiber optic and twisted pair, and also comprises multi-network configurations connecting common equipment having the multi-port interface card according to the present invention therein.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to network systems and equipment network link adapter or interface cards, in particular to media adapter or Ethernet and other network media or interface cards having multiple ports and connected to redundant or multiple systems configured therefrom.  
       BACKGROUND OF THE INVENTION  
       [0002]     Typical system networks offering redundancies include a primary and a secondary network interface or interface card connected to the appropriate network destination. When a failure is detected in the primary network connection, the error in data flow is detected, but not quickly enough to avoid losing the data transmitted during that exchange. Furthermore, the secondary network interface has a different MAC address, contributing significantly to the delay in switch-over upon detected failure of the primary network interface path.  
         [0003]     Heretofore, whenever there was a network failure, the end user always was aware of the failure, which resulted in a significant loss in data and time. Most networks attempt to provide resiliency in the core or backbone of the network, which becomes very complex when redundant paths are provided to multi-addressed fringe devices. The resulting increase in system complexity and convergence time often causes the end user to reboot their systems, or at least reconnect to the server when there is a network failure.  
       SUMMARY OF THE INVENTION  
       [0004]     The network interface cards and system according to the present invention includes a network interface main port typically connected to the user equipment or server clusters and dual (or redundant, multiple) network interface output ports through which data traffic is selectively sent, and hardware link failure detector circuitry integrated with an application or operating system-compliant driver and related GUI management software to provide operator alert and control, and controllable fail-over transfer to a secondary network link within in a predetermined software programmable time, transparent to the end user with no lost data. System implementations according to the present invention provides enhanced network data line protection and restoration in the event of data line failure. Moreover, the interface cards according to the present invention is similarly programmable to automatically restore network connections via the primary network link upon return of data activity to that link. Further embodiments of the present invention convert the input media, e.g. twisted wire pair, to a different output media, eg. Ethernet, single or multimode fiber optic.  
         [0005]     In addition, representative redundant and multiple network system configurations are provided with the media converter/interface card and media converter according to the present invention to provide enhanced performance with reduced delays and data loss and improved operator control thereof. 
     
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0006]     These and further features of the present invention will be better understood by reading the following Detailed Description together with the Drawing, wherein  
         [0007]      FIG. 1  is a block diagram of an exemplary ‘back-to-back’system embodiment having both primary and both secondary ports linked to each other according to the present invention;  
         [0008]      FIG. 2  is a block diagram of an exemplary system embodiment having both primary and both secondary ports linked to each other via redundant primary and secondary switches;  
         [0009]      FIG. 3  is an illustration of typical user GUI according to one embodiment of the present invention showing user control of switch-over parameters;  
         [0010]      FIG. 4  is a block diagram of the one embodiment of the network interface card according to the embodiments present invention of  FIGS. 1 and 2 ; and  
         [0011]      FIG. 5  is a block diagram of one embodiment according to the present invention of the Multiplexer of  FIG. 4 .  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0012]     A ‘back-to-back’ redundant network configuration  50  is provided in  FIG. 1 , wherein two switches  52 ,  54  are interconnected via interface card  60  according to one embodiment of the present invention, each having two output ports, the first ports being connected together and the second ports being connected together by twisted pair, fiber optic, or another data medium compatible with the interface card  60  output data and medium format. The interface cards optionally perform the function of translation from one medium, e.g. twisted pair (TP) from the switch  52 , to another medium, e.g. fiber optic (FO). Typically, the interface cards  60  are grouped in chassis  62  and  64  along with other interface cards  60  to be connected to other equipment (not shown) and to a corresponding management card  69 , which directs the operator selection of the interface card  60  operating parameters discussed below, to each of the selected interface cards  60  within the corresponding chassis  62 ,  64 . Each of the management cards  69  is connected, such as by serial interface, to a programmable operator system, such as a typical PC  72  having the corresponding operator and driver systems to recognize and control the management cards  62 ,  64  and the subordinate interface cards  60 . The exemplary system  50  of  FIG. 1  provides protection from the failure of data paths  66 A and  66 B as described below.  
         [0013]     An alternate system embodiment  80  is shown in  FIG. 2  wherein server clusters A and B,  82  and  84  respectively, are connected to the network interface cards  60  according to the present invention via data paths  81 ,  83  and  85 ,  87 . The network interface cards  60  are housed in a common chassis  62 A and having a common management card  69  controlled by a computer having the corresponding system and driver software components therein. Each network interface card  60  receives one of the incoming data traffic on a user selected media  81 ,  83 ,  85  and  87  and provides redundant primary and secondary output data paths  61 A and  61 B,  63 A and  63 B,  65 A and  65 B, and  67 A and  67 B on media which may differ from the incoming data path medium. In the exemplary embodiment  80  of  FIG. 2 , the network line card primary output signals  61 A and  63 A for the server cluster A,  82  are received by a switch  58  along with the network line card secondary output signal  65 B and  67 B for the server cluster B,  84 , while the interface card primary output signals  65 A and  67 A for the server cluster B,  84  are received by a switch  56  with the interface card output signals secondary output signals  61 B and  63 B for the server cluster A,  82 . The output signals data paths  57 ,  59  from the switches  56  and  58  are received by the switch  88  which provides network outputs signals along selected media  89 . The network according to the embodiment  80  of  FIG. 2  provides redundancy and switch ( 56 ,  58 ) or media failure protection as described below.  
         [0014]     As previously mentioned, one or more network interface cards  60  are controlled by a management card  65  or management module under control of a programmable controller console  76 , typically a programmed PC having the appropriate connection (e.g. serial) to the management card  65 . The console  76  includes an operating system and an application, e.g the WebBeacon™, and NetBeacon™ of Metrobility, Inc., the programs and User Guides of which being incorporated by reference, which has the necessary hardware (e.g.  65 ,  60 ) drivers and user interface (discussed below) to provide operator selection of primary/secondary switching parameters.  
         [0015]     The monitoring of the configurations of  FIGS. 1 and 2  is typically provided by a user Graphic User Interface (GUI)  90  as illustrated in  FIG. 3 . such as provided by a console machine ( 76 ) having the necessary operating system and management card  65  driver. The active port is indicated  91  as is the occurrence of a switch-over,  92  to the secondary port. In this particular GUI ‘screen shot’, we see that the SONAR (Switch On No Activity Received) is disabled. When enabled, the interface card  60  switch (or &#39;Fail-Over) from primary to secondary port occurs when the active port stops receiving activity as determined by the PHY hardware on the interface card  60 , discussed below. A Dynamic Recovery Mode is selected at  94 . Automatic restoration to the primary port circuit (from the secondary port) is selected as indicated at  96 , and the time (1-32 seconds) after switch-over to occur after the conditions, e.g. SONAR active indicate that the primary port is inactive or otherwise a switch-over is required is shown at  99 . A further feature is to verify the data traffic on the secondary port circuit before the interface line card switches to the secondary port. Such GUI controls provide operator control of the interface card  60  as provided by software controls (e.g. NetBeacon) of the interface card  60  internal registers by available programming techniques.  
         [0016]     A block diagram  100  of one embodiment of the present invention is shown in  FIG. 4 , wherein the main port  102  interface connects to the equipment  62  and to the Main PHY  104 , which is in turn connected to the Multiplexer  106  main port connections. The Multiplexer  106  primary port connections are received by the Primary PHY  108 , which is in turn connected to the Primary Port interface  110 . Similarly, the Multiplexer has secondary port connections received by a Secondary PHY  112 , which is in turn connected to the Secondary Port interface  114 . The interfaces  102 ,  112  and  114  provide an interface from the respective PHY protocol to 1000Base-T, 1000Base-X, Gigabit Ethernet. When enabled, the selected primary or secondary port will translate the data to GMII format, for example, and communicate via the Multiplexer  106  with the Main port after being translated back from GMII format. Also, the converse communication flow is provided as well. Other internal and external data formats are within the scope of the present invention, and media conversion is provided by providing the corresponding media main, primary and secondary ports ( 102 ,  110  and  114 ) and PHY layers ( 104 ,  108  and  112 ).  
         [0017]     Each of the Primary and Secondary PHY  108 ,  112  also provides a logic signal indicating the presence of data activity from the corresponding port interface  110 ,  114 , which signals are received by a Link Activity Detector logic  120 , typically implemented on Complex Programmable Logic Devices (CPLD), to provide a control signal to the Multiplexer  106  (enable primary RCV and enable primary TX,  FIG. 5 , below) according to the detected primary or secondary port activity (or inactivity) and according to control signals provided by the Management Logic and Timer  122 . The Management Logic and Timer  122  receives control signals from the host computer (console), e.g.  72 , via the backplane connector  126  according to the operator selections made via the GUI  70  of  FIG. 3 . The Management Logic and Timer  122  includes a timer set according to the GUI directives for 1-32 (typically) seconds to elapse after an inactive status is received from the selected primary or secondary PHY  108 ,  112 , after which an ‘end-of-time’ signal is generated which together with a detection of activity on the other port circuit PHY, causes or enables the Multiplexer  106  to switch from one (of primary or secondary) to the other port. Additional interface card  60  functions are selectively controllable via switches  124  located on each interface card  60 . If the ‘Auto Restore’ feature is enabled  76 ,  FIG. 3 , the data will again be redirected via the Management Logic  122 , Link Activity Detector  120  and Multiplexer  106  to initially selected link upon return of data activity as indicated by the corresponding activity status signal. Other greater or lesser time intervals may be accommodated by the Management Logic and Timer  122  according to the present invention.  
         [0018]     The internal structure of the Multiplexer CPLD  106  is shown in  FIG. 5 , wherein the primary-to-main port transmit (TX) and receive (RCV) paths are provided and active according to signals on the corresponding enable primary TX and RCV inputs; otherwise, the RX and RCV data paths are provided between the secondary and main port connections.  
         [0019]     Modifications and substitutions according to the present invention are within the scope of the present application, which is not to be limited except by the claims which follow. Moreover, while the multi-port interface card/media converter according to the present invention is illustrated by exemplary embodiments having two data links, the scope of the present invention also includes embodiments having additional secondary ports selectably enabled and accessed as describe above regarding two output ports. Such additional secondary ports are configured from additional physical port circuits, multiplexers having correspondingly wider input/output capacities, larger control/status registers and correspondingly expanded software driver control and support.