Patent Publication Number: US-2021168961-A1

Title: Adjustable cable management bracket for modular electronic system

Description:
STATEMENT OF RELATED APPLICATION 
     The present application is a continuation of U.S. patent application Ser. No. 16/001,835, entitled ADJUSTABLE CABLE MANAGEMENT BRACKET FOR MODULAR ELECTRONIC SYSTEM, filed Jun. 6, 2018 (Attorney Docket No. CISCP1345), which is hereby incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to network communications devices, and more particularly, to cable management for modular electronic systems. 
     BACKGROUND 
     Modular electronic systems are designed to provide flexibility to configure systems as per user needs. These systems typically have multiple slots to accommodate a variety of modules. With increased packaging density of networking interconnects to provide higher bandwidth, effective cable management is becoming an increasingly important issue. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective of a cable support system installed on a modular electronic system, in accordance with one embodiment. 
         FIG. 2A  is front view of the cable support system and modular electronic system shown in  FIG. 1 . 
         FIG. 2B  is front view of the cable support system installed on another modular electronic system. 
         FIG. 3  illustrates cables connected to the modular electronic system and routed on the cable support system shown in  FIG. 2A . 
         FIG. 4  is a perspective of a cable management bracket of the cable support system shown in  FIG. 1 . 
         FIGS. 5A-5C  illustrate steps for unlocking, rotating, and adjusting the cable management bracket shown in  FIG. 4 . 
         FIG. 6  is a perspective of a cable management bracket with an adjustable width, in accordance with one embodiment. 
         FIG. 7  is a top view of a cable management bracket with an adjustable depth, in accordance with one embodiment. 
         FIG. 8  is a perspective of a cable management bracket with thumb screw adjustment for bracket orientation, in accordance with another embodiment. 
         FIG. 9A  is a perspective of another embodiment of the cable support system installed on the modular electronic system. 
         FIG. 9B  is a front view of the cable support system and modular electronic system shown in  FIG. 9A . 
         FIG. 10A  is a perspective of a cable management bracket in accordance with another embodiment. 
         FIG. 10B  illustrates the cable management bracket of  FIG. 10A  attached to a module in a modular electronic system. 
         FIGS. 11A and 11B  illustrate the cable management bracket of  FIG. 10A  positioned to allow for filter replacement in the modular electronic system. 
         FIG. 12A  illustrates a line card and an adjustable line card cable bracket, in accordance with one embodiment. 
         FIG. 12B  shows the adjustable line card cable bracket of  FIG. 12A  connected to the line card. 
         FIGS. 13A and 13B  illustrate another embodiment of the adjustable line card cable bracket. 
         FIG. 14  illustrates another embodiment of the adjustable line card cable bracket. 
         FIG. 15A  illustrates yet another embodiment of the adjustable line card cable bracket in a closed position. 
         FIG. 15B  illustrates the adjustable line card cable bracket of  FIG. 15A  removed from the line card. 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views of the drawings. 
     DESCRIPTION OF EXAMPLE EMBODIMENTS 
     Overview 
     In one embodiment, a cable management bracket for managing cables connected to a modular electronic system mounted on a rack comprises a fixed portion and a rotatable portion extending from the fixed portion and comprising a support member for supporting the cables, the rotatable portion rotatable with the cables to allow for removal and insertion of a module of the modular electronic system. 
     In another embodiment, an apparatus generally comprises a module receivable in a modular electronic system and a cable management bracket for managing cables connected to the modular electronic system, the cable management bracket comprising a fixed portion connected to the module and a rotatable portion extending from one end of the fixed portion and movable with the cables when installed in the modular electronic system to allow removal and insertion of a field replaceable unit of the modular electronic system. 
     In yet another embodiment, an apparatus generally comprises a line card receivable in a modular electronic system, arms extending from a front panel of the line card, and a cable support bracket configured for connection to the arms. The cable support bracket is configured for connection to the arms in at least two different positions, each of the positions spacing the cable support bracket a different distance from the front panel of the line card. 
     Further understanding of the features and advantages of the embodiments described herein may be realized by reference to the remaining portions of the specification and the attached drawings. 
     Example Embodiments 
     The following description is presented to enable one of ordinary skill in the art to make and use the embodiments. Descriptions of specific embodiments and applications are provided only as examples, and various modifications will be readily apparent to those skilled in the art. The general principles described herein may be applied to other applications without departing from the scope of the embodiments. Thus, the embodiments are not to be limited to those shown, but are to be accorded the widest scope consistent with the principles and features described herein. For purpose of clarity, details relating to technical material that is known in the technical fields related to the embodiments have not been described in detail. 
     Network devices such as switches, routers, servers, or other electronic devices may be configured as a modular electronic system with a plurality of removable modules (e.g., service cards, line cards, optical modules, fabric cards, power supply units (PSUs), fans (fan trays), filters, or other cards, components, or modules). Many of the modules include ports connected to data or power cables that are routed in such a way that can interfere with access to other modules. 
     In a modular electronic system, Online Insertion and Removal (OIR) describes a process of replacing a module for repair or replacement (e.g., product upgrade, failed module replacement) while the network device is operational, without disrupting performance of the modular system. During this process, the system continues to be functional and a faulty module is replaced with a new or repaired module. Since remaining modules are still operational, module OIR needs to take place without disconnecting or interfering with cables connected to the remaining modules. Modularity thus creates many limitations on cable management. 
     Moreover, it is desired and often required to maintain cable bend radius and in some cases, mixing of optical and electrical cables is not allowed. Many service providers also have very stringent cable management guidelines for directional exit of the cables. These requirements become more complicated for modular platforms, where cable management is expected to not interfere with accessibility of the modules during installation or servicing. 
     The embodiments described herein provide cable management for high-density modular platforms. In one or more embodiments, a cable support system comprises cable management brackets positioned to manage cables connected to modules in a modular electronic system and allow for insertion and removal of a module without interfering with cables connected to other modules. In one or more embodiments, the cable management bracket comprises a fixed portion and a rotatable portion rotatable with the cables to allow for insertion and removal of the modules. The cable management bracket may be connected to a rack supporting the modular electronic system, for example, and positioned above or below the modular electronic system for movement of the rotatable portion without disconnecting the cables. The cable management bracket may also be connected to a module with a rotatable portion extending from one end of the fixed portion to allow for removal and insertion of an adjacent module (field replaceable unit). As described in detail below, the cable support system may comprise many adjustable features to properly align the cable bracket with an exit position of the cable on the module. The cable brackets of the cable support system may be independently configured to manage cables and access the modules during OIR, without disturbing cable routing from other modules. In one or more embodiments, dimensions and positions of the cable management bracket may be optimized for any configuration system to provide independent access to all modules. 
     Referring now to the drawings, and first to  FIG. 1 , an example of a network device (modular electronic system)  10  that may implement the embodiments described herein is shown. The modular electronic system  10  may operate, for example, as a switch, router, server, or any other network device comprising modules (components, cards, trays, elements, units) included in modular sections. In one or more embodiments, the network device  10  operates in a data communications network including multiple network devices that may communicate over one or more networks (e.g., local area network (LAN), metropolitan area network (MAN), wide area network (WAN), virtual private network (VPN) (e.g., Ethernet virtual private network (EVPN), layer 2 virtual private network (L2VPN)), virtual local area network (VLAN), wireless network, enterprise network, corporate network, data center, Internet, intranet, radio access network, public switched network, or any other network). 
     In one or more embodiments, the modular electronic system  10  is a programmable machine that may be implemented in hardware, software, or any combination thereof. The modular electronic system  10  may include one or more processor, memory, and network interface. Memory may be a volatile memory or non-volatile storage, which stores various applications, operating systems, modules, and data for execution and use by the processor. The network interfaces may comprise any number of interfaces (e.g., line cards, ports) for receiving data or transmitting data to other devices. 
     As shown in  FIG. 1 , the modular electronic system  10  comprises a plurality of modules  14 ,  16  contained within a frame  12 . The system  10  may include one or more frames or structures  12  configured to support various components and slidably receive any number of removable modules  14 ,  16 .  FIG. 1  shows a front portion of the frame  12  comprising openings for receiving a plurality of modules  14 ,  16 . The example shown in  FIG. 1  includes two rows of line cards  14 , with two line cards in each row and a controller card  16  installed on one side of the line cards. Configurable guides may be inserted into the opening of the front panel to define any number of slots for receiving different size modules. Any number of power supply units and fans may be inserted at a rear panel (not shown) of the modular electronic system  10 . 
     In another example, the modular electronic system may include one row of optical modules along with management and control interfaces (as described below with respect to  FIG. 2B ). Another modular electronic system may include, for example, one column of stacked line cards comprising service cards and controller cards with a fan tray located adjacent to one edge of the line cards and an air filter positioned adjacent to the other edge of the line cards (as described below with respect to  FIGS. 11A and 11B ). It is to be understood that the type, number, and arrangement of components and modules shown and described herein are only examples and the modular electronic system may include any number or type of modules arranged in any format, without departing from the scope of the embodiments. 
     The term module as used herein refers to any module, component, or field replaceable unit of the modular electronic system, including, for example, line cards, optical modules, controller cards, fabric cards, service cards, combo cards, fan trays, power supply units, filters, and the like. The module may comprise, for example, a line card connected to cables or a field replaceable unit (e.g., filter) adjacent to the line card. 
     The term cable as used herein refers to any type of cable connected to the modular electronic system, including, for example, cable carrying data (e.g., Ethernet, fiber optics, optical array, fabric), power, cooling, or any combination thereof. The cable may comprise, for example, fiber data cables, copper data cables, copper power cables, hybrid cables (e.g., data and power cables, data, power, and cooling cables), and the like. 
     The modular electronic system (network device)  10  may be rack mounted in a rack system  18  (e.g., two or four post rack mounting system with slider brackets) configured to support a plurality of network devices. Each rack bracket comprises a plurality of openings  19  for alignment with a support bracket, which may be connected to the frame  12  of the modular electronic system  10 . In the example shown in  FIG. 1 , only one modular electronic system  10  is installed on the rack  18 , however, any number of network devices may be installed above or below the modular electronic system. 
     One or more of the modules  14 ,  16  shown in  FIG. 1  may be removed for repair or replacement while the other components remain operational. The term OIR (Online Insertion and Removal) as used herein refers to removal of a module from the modular electronic system  10  without removing power from the modular electronic system (i.e., one or more remaining modules are operational). One or more of the modules may be removed and a new module (or repaired module) inserted during the OIR process with the remaining modules operational, or while the modular electronic system  10  (or one or more of the remaining modules) is not operating. 
     Without the cable support system described herein, the cable routing from the line cards  14  may interfere with the insertion and removal of adjacent modules because the cables may obstruct access to the module. For example, cables from the line cards  14  located on the right side of the network device  10  (as viewed in  FIG. 1 ) would block access to the controller card  16  on the right if the cable routing exits to the right or the line cards  14  on the left if the cable routing exits to the left. For module OIR, all of the cable routing would need to be readjusted, which is not desirable in production networks. Another concern is that optical fibers from the line cards  14  would pass over the controller card  16  and mix with the electrical cable. The cable support system described herein allows for access to modules for OIR without the need to remove or readjust cables connected to adjacent modules, while also managing cables to maintain bend radius and preventing mixing of optical and electrical cables. 
     In one or more embodiments, the cable support system comprises one or more cable management brackets, generally indicated at  15 , installed above or below the modular electronic system  10  ( FIG. 1 ). Each cable management bracket  15  comprises a brace (fixed portion)  20  and one or more rotatable cable brackets (rotatable portions)  22  connected to the fixed portion and operable to move (rotate) between an operating position (as shown for the brackets positioned in front of line cards  14  on the left side of the modular electronic system  10  and the lower line card on the right side of the modular electronic system in  FIG. 1 ) and a module removal position (as shown for the bracket associated with the upper module being removed on the right) to move the bracket and cables out of the way to allow for removal of the module. 
     The fixed portion (brace)  20  may comprise, for example, a metal bar extending horizontally between vertical posts of the rack  18  with openings  21  at each end aligned with the openings  19  on the rack for receiving a fastener (not shown). In the example shown in  FIG. 1 , each brace  20  is located immediately above or below the modular electronic system  10 , with the cable support system occupying space on the rack equivalent to approximately one rack unit (RU) (0.5 on top and 0.5 on bottom). In the example shown in  FIG. 1 , support blocks (hinge members)  25  connect the rotatable portion  22  to the fixed portion  20 . 
     The cable management bracket  15  shown in  FIG. 1  is configured with one of the rotatable cable brackets  22  corresponding to each line card  14 . Thus, the cable support system includes two cable management brackets  15  (one below and one above the modular electronic system  10 ), with each cable management bracket comprising one brace (fixed portion)  20  and two rotatable portions  22  for routing cables from corresponding modules  14 . Each rotatable bracket  22  may be independently configured to manage cables and allow access to the modules card  14  during OIR without distributing the cable routing from other line cards  14 ,  16  or readjusting the cables disconnected from the OIR module. As previously noted, dimensions and positions of the cable management brackets (fixed portion  20  and rotatable portion  22 ) may be optimized for any modular electronic system design to provide access to all field replaceable modules. 
     The rotatable portion  22  comprises a cable support member  24  connected to support blocks  25  by arms  26 . The support member  24  may be connected to the arms  26  by a fastener (e.g., bolt, screw, thumb screw, pin)  23 . In one or more embodiments, the supporting member  24  may rotate about the fastener  23  to provide additional flexibility in alignment of the cable bracket for proper routing of the cables. The support member  24  may include any number of openings  32  for receiving tie downs to secure the cables in place. As described below, the arms  26  are connected to the support blocks  25  with a hinge pin  27  extending through aligned openings in the support blocks and arms  26  to allow rotation about an axis (X in  FIG. 1 ). In one or more embodiments, the rotating portion  22  may be attached to the fixed portion  20  with a spring loaded mechanism and guide pin assembly so that the rotating portion may be locked into position (e.g., operating position or module removal position), as described below with respect to  FIG. 4 . The locking position may be defined based on the angle or movement needed for an application or deployment of the bracket and there may be more than one locking position (e.g., varying angles of rotation of the rotatable portion  22  relative to the fixed portion  20 ). 
     As described below, the cable management bracket  15  may comprise any number of adjustment features to align the bracket with the position of ports  29  on the front panel of the line cards  14 . A plurality of clips (“C” clips)  28  may be included on the arms  26  of the cable bracket and positioned based on the cable routing directions and assist with cable routing and maintaining cable bend radius requirements. The clips  28  may be provisioned on both the left and right side of the cable bracket arm  26 , or only one side and may be configured as needed during installation. 
       FIG. 2A  is a front view of the modular electronic system  10  and cable support system shown in  FIG. 1  with all of the modules  14 ,  16  installed. As previously noted, the cable support system may be installed on different configuration modular electronic systems. For example, as shown in  FIG. 2B , a modular electronic system  36  may include only one row of modules  38 . In this example, the fixed portion  20  may be located either above or below the modular electronic system  36  with each rotating portion  22  individually rotatable to allow for insertion and removal of the module  38  without removing or readjusting cables connected to the remaining modules. 
       FIG. 3  shows cables  30  installed and supported by the cable support system. For simplification, only one cable is shown for each module  14 ,  16 . As shown in  FIG. 3 , the cables  30  may pass through the clips  28  located on the arms  26  of the cable brackets. In this example, cables  30  from the left line cards  14  exit left and cables from the right line cards exit right. This arrangement may be modified based on deployment preferences. For example, the cables may exit in either direction to avoid mixing of different types of cables. The cable clips  28  may then be assembled based on the cable exit direction. The cables  30  may be tied down with Velcro straps, wire, tie downs, or any other fastener operable to secure the cable to the support member  24 . With this arrangement, the modules  14 ,  16  have independent cable routing without obstructing any other module. During module OIR, the cables  30  may remain attached to the bracket (rotatable portion)  22  while the bracket is rotated to a default straight orientation, thus providing clear access for module removal or insertion. Once the bracket configuration is adjusted according to the cable exit from the module, no tools are needed to orient the bracket during module OIR and the rotatable portion  22  of the cable management bracket can be easily rotated by hand. 
     In one or more embodiments, the clips  28  or Velcro straps may be color coded to identify the fiber assignment to respective ports. This helps when the line card is removed with the cables  30  attached to the bracket. The same cables  30  may then be properly connected when a new line card is installed. The fasteners used to attach the cables to the bracket may be multi-loop and multi-colored, for example. 
       FIG. 4  illustrates a locking mechanism (shown in detail in exploded view) of the cable management bracket  15 , in accordance with one embodiment. As previously described, the locking mechanism may be used to lock the rotatable portion  22  of the bracket in a fixed operating position or in a module removal position in which the rotatable portion and cables supported by the bracket are moved away from the module to allow for removal and insertion of the module. As described further below with respect to  FIGS. 6 and 7 , additional adjustment may also be provided to align the cables exiting the line cards. 
     In the example shown in  FIG. 4 , the locking mechanism comprises a bolt (or other fastener)  40  connecting the support block  25  attached to the brace  20 , to the arms  26  of the rotatable portion  22 . The bolt  40  and hinge pin  27  (connecting the other arm  26  to the brace  20 ) provide an axis of rotation for the rotatable portion  22 . A spring  42  maintains the bracket in its locked position with guide pin  44  inserted into one of a plurality of openings  46 . There may be any number of openings  46  to provide multiple locking positions for use in supporting cable or allowing for module OIR. For example, the different locking positions provided by the guide pin  44  and openings  46  may be used to align the cables with the connected ports on the line cards. As previously noted, the angle of the support member  24  relative to the arms  26  may be adjusted through loosening of thumb screw  23  to align the cable exit from the line card and meet bend radius requirements. 
       FIGS. 5A-5C  illustrate rotational adjustment of the cable management bracket shown in  FIG. 4 . In order to unlock the bracket, the rotatable portion  22  is slid to the right (as viewed in  FIG. 5A ) to release the guide pin  44  from opening  46  against the spring force ( FIGS. 4 and 5A ). The rotatable portion  22  of the bracket may then be rotated up or down based on the line card position ( FIG. 5B ). When the bracket is released, the guide pin  44  locks in the closest hole  46  ( FIGS. 4 and 5B ). The angle of the support member  24  may then be adjusted to align with the cable exit position of the ports  29  on the front panel of the line card  14  ( FIGS. 1 and 5C ). 
       FIG. 6  illustrates a cable management bracket comprising a fixed portion  60  and a rotatable portion  62  with an adjustable width. Adjustment of the bracket width allows the bracket to fit within any modular electronic arrangement with various size line cards. The fixed portion (brace)  60  includes horizontal slots  63  that allow support blocks  65  connecting arms  66  to the brace to move and thereby change the spacing between connection points. The width of the support member  64   a ,  64   b  is also adjustable through slot  67  and fastener  68  so that the width of the support member corresponds to the distance between the support blocks  65 . As shown in the exploded view, one side  64   a  of the support member is slidably receivable in the other side  64   b  of the support member and the two members are locked in place with the fastener  68 . This feature allows the cable management bracket to be adjusted to any dimension based on the width of the module thereby providing flexibility and implementation on different modular electronic systems. 
     As shown in  FIG. 7 , the distance between support member  74  and fixed portion  70  of the cable management bracket may also be adjusted. Extendable arms may accommodate different types of optical transceivers or cable bend radius requirements and allow for different types of deployments, including deployments configured in accordance with one or more standard. In this example, each arm of the bracket comprises two mating members  76   a ,  76   b  connected by a fastener  79  (shown in cross-section in  FIG. 7 ). Arm member  76   b  comprises a slotted opening  77  for receiving the fastener  79  and positioning the arms with a set length. Support block  75  may connect the rotatable portion of the bracket to the fixed portion  70  with locking mechanism  72  and support member  74  may rotate about fastener  73 , as previously described. 
       FIG. 8  is a schematic illustrating another example of a bracket adjustment mechanism that may be used to properly orient a rotatable portion  82  of the cable management bracket relative to a fixed portion  80 . In this example, thumb screws  83  secure arms  86  of the bracket to links  85  in a fixed orientation relative to the fixed portion  80  of the cable support system. Thumb screws  83  may be loosened to provide angular orientation of the rotatable portion  82  of the bracket. The rotatable portion  82  is rotatably connected to the fixed portion  80  through links  85  and locking member  87  may lock the rotatable portion  82  in a fixed position, as previously described. 
       FIGS. 9A and 9B  illustrate another embodiment of the cable supporting system. In this example a rotating portion  92  of the cable management bracket is attached to hinged members  94 , which are connected to brace  90 . Each hinge member  94  comprises an internal locking mechanism (e.g., friction fit or indexed locking positions) that allow for rotation of the rotating portion  92  of the bracket. In this example, clips  98  are attached to the fixed portion  90  of the cable support system rather than the rotating cable bracket  92 . Although not shown, clips may also be included on the cable bracket  92 . 
     It is to be understood that the cable management bracket (fixed portion, rotating portion, support member, locking mechanism, clips, adjustment features) shown in  FIGS. 1, 2A, 2B, 3, 4, 5A, 5B, 5C, 6, 7, 8, 9A, and 9B  and described above are only examples and that other configurations, mechanisms, fasteners, or arrangements may be used, without departing from the scope of the embodiments. 
     Also, the modular electronic systems  10 ,  36  shown in  FIGS. 1-3, 9A, and 9B  are only examples and the modular electronic system, rack, or size, number, or arrangement of modules may be different than shown, without departing from the scope of the embodiments. For example, as previously noted, the modular electronic system may contain any number of rows of modules, with each row containing any number of modules, or any size or type of modules, with any number of ports or interfaces. The rack mounted network device may have a height, for example of 1RU (rack unit), 2RU, or any other height. If there is only one row of line cards, only one cable management bracket is needed and may be mounted above or below the network device. 
     The modular electronic system may comprise for example, a transponder platform (e.g., Cisco NCS 1004 and the like) ( FIG. 1 ), DWDM (dense wavelength-division multiplexing) line system (e.g., Cisco Network Convergence System (NCS) 1001 and the like) ( FIG. 2B ), or any convergence system, router, switch, server, or other modular electronic system. 
       FIGS. 10A and 10B  illustrate an example of a cable management bracket, generally indicated at  115 , installed on a line card in a rack mounted modular electronic system (network device)  110 .  FIG. 10A  is a perspective of a front panel  108  of the line card with the line card management bracket  115  attached. For simplification, cable interfaces and ports are not shown and only the front panel of the line card is shown. The modular electronic system  110  may comprise, for example, a network convergence system such as Cisco NCS 2006, or any other modular electronic system. As shown in  FIG. 10B , the modular electronic system  110  comprises a rack mounting bracket  118  and an opening  112  for receiving a plurality of line cards. In operation, all of the slots in opening  112  of the modular electronic system  110  may be filled. The modular electronic system  110  is attached to a rack (not shown) with the rack mounting bracket  118  (one on each side of the modular electronic system  110 ). 
     The cable management bracket  115  comprises a fixed portion  120  and a rotatable portion  122 . The fixed portion  120  comprises a generally U-shaped member comprising a horizontal portion  121  and two arms  123  extending generally perpendicular therefrom. Each arm  123  is fixedly attached to opposite ends of the line card front panel  108 , with the rotatable portion extending from one arm of the fixed portion  120 . The rotatable portion  122  is rotatable about an axis (Y in  FIG. 10A ) extending along a hinged connection to the arm of the fixed portion to which the rotating portion is attached. In one embodiment, the rotating portion  122  is held in place by rotating guide arm  124 , which may be locked in place by tightening thumb screw  126 , for example. 
     The guide arm  124  is positioned below the rotating cable support member  122 , which moves with the guide arm The cable management bracket may also include openings (not shown) for securing the cables thereto or clips for routing the cables, as previously described with respect to  FIG. 1 . 
       FIGS. 11A and 11B  illustrate operation of the cable management bracket  115  during removal of an air filter (field replaceable unit, module)  130  located adjacent to one edge of the line cards. The rotatable portion  122  allows for clear access to the filter  130  so that the cable routing does not obstruct filter access during replacement. A default position of the bracket is shown in  FIGS. 10A and 10B . The rotatable portion  122  of the bracket may be rotated up (as shown in  FIG. 11A ) or down (as shown in  FIG. 11B ) depending on the location of the line card within the modular electronic system  110 . Movement of the rotating portion  122  allows the line card to be installed in any of the slots while still providing clear access to the filter  130  or any other module located adjacent to the line cards (on either side of the line cards). If cables are routed exiting to the left and to the right of the line cards and if access to modules is needed on both sides of the line cards, the bracket may include rotating portions  122  extending from both ends of the fixed portion  120 . The cables are moved with the rotating portion  122  of the bracket without the need for removing or readjusting the cables. As previously noted, the modular electronic system  110  may include any number of modules in any arrangement. 
     One or more of the line cards may be installed in the modular electronic system  110  without the cable management bracket  115 . For example, only two (or more) of the line cards may be installed with the cable management bracket  115  and cables from all of the line cards routed over these two brackets, or some of the cables may be routed through other cable guides installed on the modular electronic system  110  or rack. The cable management bracket  115  may be installed only on line cards with a large number of cable connections, for example. In another example, optical fibers may be routed over existing cable guides and thicker Ethernet cables routed on the cable management bracket  115 , thereby preventing the mixing of optical fibers with other cables. 
       FIGS. 12A and 12B  illustrate an example of a line card cable support bracket  144  that may be attached to the individual line cards  14 . The cable support bracket  144  may be used, for example, in place of the cable management bracket  15  in  FIG. 1  or one or more of the line cards  14  in  FIG. 1  may include the line card cable support bracket shown in  FIG. 12A  instead of having a corresponding rotatable bracket  22 . If all line cards in a row include the line card cable support bracket  144  in place of the cable management bracket  15  shown in  FIG. 1 , space may be freed up above or below the modular electronic system. If the cable management bracket  15  shown in  FIG. 1  is used with the modular electronic system  10 , the line card  14  may only include arms  142 , which aid insertion and extraction of the line card, without interfering with the cable management bracket  15  ( FIGS. 1 and 12A ). 
     In one or more embodiments, the bracket  144  comprises a U-shaped member configured for connection with the arms  142  attached to the line card  14 . As shown in  FIG. 12A , the arms  142  include at least two openings  145  for receiving a connecting member  143 , with the bracket  144  so that the bracket may be spaced from a front panel  146  of the line card with at least two different spacings. In one or more embodiments, spring plungers  143  are used to lock the cable support bracket  144  in place in a position spaced from the front panel  146  of the line card  14  at different distances based on which opening the plunger is inserted to support different fiber bend radius and various deployment conditions. In the example shown in  FIGS. 12A and 12B , arms  142  are attached to a lower face of the line card  14  and extend outward therefrom. 
     The cable support bracket  144  may be formed from a rigid metal such as iron or steel, for example. The bracket  144  is preferably sufficiently thin to be mounted in front of the line card  14  while not obstructing adjacent line cards located above or below the line card and sufficiently thick to support cables. The bracket  144  may be formed from stamping or molding, for example, and may include any number of openings  147  for receiving tie downs to secure cables in place. The bracket  144  may be used as handle for use in removing or inserting the line card  14 . 
     In another embodiment shown in  FIGS. 13A and 13B , a cable support bracket (handle)  154  slides over arms  152  attached to the line card. The arms  152  include slots  156  for receiving fasteners  153  with the bracket  154  positioned at varying distances from the front panel  146  of the line card  14 . In one embodiment, the fastener  153  is a spring loaded fastener with an exposed button that may be depressed to release the fastener and allow for sliding movement between the bracket  154  and arms  152  extending from the line card  14 . After the bracket depth is adjusted, the button is released to allow the spring to force the fastener into its locked position, thereby retaining the bracket in a fixed positioned spaced from the front face  146  of the line card. The fastener  153  combines the attachment feature and keyhole adjustment feature into one spring loaded plunger, as described further below with respect to  FIGS. 15A and 15B . The sliding insertion/removal feature eliminates the need for space below or above the line card bracket for removing the bracket in an upward or downward position. 
       FIG. 14  illustrates a cable support bracket  164  that is pivotably connected to arms  162  and may be swung open to access a highly dense interconnect pluggable on the front panel  146  of the line card  14 , for example. In this example, the arms  162  comprise slidably mating members that allow for adjustment of the distance between the bracket  164  and the front panel  146  of the line card  14 . The bracket  164  may swing open in either direction by removing thumb screws  168  located on each side of the bracket. 
       FIGS. 15A and 15B  illustrate another embodiment of the adjustable line card bracket. This embodiment is similar to the embodiment shown in  FIGS. 13A and 13B  except the spring plunger is moved from the bracket to the line card arms. A bracket  174  is slidably receivable in a channel formed in arms  172  connected to the line card  14 . A spring loaded plunger  173  is mounted on the arms  172  and extends into the channel. The plunger  173  includes a button  175 , which may be depressed to force a shaft of the plunger through opening  178  in the bracket  174 . A bottom of the shaft is small enough to fit through opening  178  but larger than adjacent slot  176 . The button  175  of the plunger  173  may be depressed to insert or remove the bracket  174  from the line card arms  172  when the bracket is positioned such that the plunger is aligned with openings  178 . The bracket  174  may then be moved to its desired position as the shaft of the plunger slides along the slot  176 . Once the button  175  is released the bracket  174  is locked in place relative to arms  172 . The adjustment feature of the fastener allows for adjustment of the bracket  174  to different depths for different fiber bend requirements and also allows the bracket to be moved to a deeper or extended position, as needed to meet deployment needs. Location of the fasteners  173  at an end portion of the arms  172  allows for easy access to the fastener. The spring loaded, press button fastener  173  provides for both installation/removal of the bracket  174  and adjustment of the bracket depth without tools. In one example, the cables may be disconnected from the line card  14  and the line card replaced without detaching the cables from the system. The bracket (handle)  174  may also be removed to provide better accessibility to the pluggable elements on the front panel  146  of the line card. 
     It is to be understood that the line card cable support brackets  144 ,  154 ,  164 , and  174  are only examples and that different types of adjustment means or connectors may be used, without departing from the scope of the embodiments. 
     Although the method and apparatus have been described in accordance with the embodiments shown, one of ordinary skill in the art will readily recognize that there could be variations made to the embodiments without departing from the scope of the embodiments. Accordingly, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.