Patent Publication Number: US-8121458-B2

Title: Fiber distribution hub with swing frame and modular termination panels

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of application Ser. No. 11/354,286, filed Feb. 13, 2006, now U.S. Pat. No. 7,720,343; which application is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     Passive optical networks are becoming prevalent in part because service providers want to deliver high bandwidth communication capabilities to customers. Passive optical networks are a desirable choice for delivering high-speed communication data because they may not employ active electronic devices, such as amplifiers and repeaters, between a central office and a subscriber termination. The absence of active electronic devices may decrease network complexity and/or cost and may increase network reliability. 
       FIG. 1  illustrates a network  100  deploying passive fiber optic lines. As shown, the network  100  can include a central office  101  that connects a number of end subscribers  105  (also called end users  105  herein) in a network. The central office  101  can additionally connect to a larger network such as the Internet (not shown) and a public switched telephone network (PSTN). The network  100  can also include fiber distribution hubs (FDHs)  103  having one or more optical splitters (e.g., 1-to-8 splitters, 1-to-16 splitters, or 1-to-32 splitters) that generate a number of individual fibers that may lead to the premises of an end user  105 . The various lines of the network  100  can be aerial or housed within underground conduits. 
     The portion of the network  100  that is closest to central office  101  is generally referred to as the F 1  region, where F 1  is the “feeder fiber” from the central office  101 . The portion of the network  100  closest to the end users  105  can be referred to as an F 2  portion of network  100 . The network  100  includes a plurality of break-out locations  102  at which branch cables are separated out from the main cable lines. Branch cables are often connected to drop terminals  104  that include connector interfaces for facilitating coupling of the fibers of the branch cables to a plurality of different subscriber locations  105 . 
     Splitters used in an FDH  103  can accept a feeder cable F 1  having a number of fibers and may split those incoming fibers into, for example, 216 to 432 individual distribution fibers that may be associated with a like number of end user locations. In typical applications, an optical splitter is provided prepackaged in an optical splitter module housing and provided with a splitter output in pigtails that extend from the module. The splitter output pigtails are typically connectorized with, for example, SC, LC, or LX.5 connectors. The optical splitter module provides protective packaging for the optical splitter components in the housing and thus provides for easy handling for otherwise fragile splitter components. This modular approach allows optical splitter modules to be added incrementally to FDHs  103  as required. 
     SUMMARY 
     Certain aspects of the disclosure relate to fiber optic cable systems. 
     In example systems, a fiber distribution system includes one or more fiber distribution hubs (FDHs) that provide an interface between the central office and the subscribers. 
     Certain aspects of the invention relate to cable routing configurations. 
     Other aspects of the invention relate to enhanced access and scalability through the use of modular subscriber termination components and modular splitters. 
     A variety of additional inventive aspects will be set forth in the description that follows. The inventive aspects can relate to individual features and to combinations of features. It is to be understood that both the forgoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the broad inventive concepts upon which the embodiments disclosed herein are based. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a passive fiber optic network; 
         FIG. 2A  is a front perspective view of an example fiber distribution hub having a cabinet with front doors shown in a closed position; 
         FIG. 2B  is a front perspective view of the fiber distribution hub of  FIG. 2A  with the cabinet doors shown in an open position; 
         FIG. 2C  is a front perspective view of the fiber distribution hub of  FIG. 2A  with a swing frame swung out of the cabinet; 
         FIG. 3  is a schematic diagram showing an example cable routing scheme for the fiber distribution hub of  FIG. 2A ; 
         FIG. 4  is a front perspective view of the swing frame of  FIG. 2C  isolated from the fiber distribution hub; 
         FIG. 5  is a front side view of the swing frame of  FIG. 4 ; 
         FIG. 6  is a right side view of the swing frame of  FIG. 4 ; 
         FIG. 7  is a top view of the swing frame of  FIG. 4 ; 
         FIGS. 8A-8C  show one example of a splitter module of the distribution hub of  FIG. 2A ; 
         FIG. 9  shows an example splitter module having eight output fibers including connectorized ends secured to a storage module; 
         FIG. 10  depicts one example cable/fiber route from a splitter module mounted on a swing frame to a storage module mounted on the swing frame; 
         FIG. 11  depicts on example cable/fiber route from a splitter module mounted on a swing frame to a termination module mounted on the swing frame; 
         FIGS. 12A and 12B  are front and rear perspective views of an example termination module of the distribution hub of  FIG. 2A ; 
         FIG. 13  is a rear perspective view of the swing frame of  FIG. 4 ; 
         FIG. 14  is another perspective view of the swing frame of  FIG. 4 ; 
         FIG. 15  is a left side view of the swing frame of  FIG. 4 ; 
         FIG. 16  is a rear view of a swing frame including example interface devices and cable management devices mounted at the rear side of a swing frame; 
         FIG. 17  is a rear perspective view depicting one example configuration of interface devices and cable management devices on a swing frame; 
         FIG. 18  is a rear perspective view depicting another example configuration of interface devices and cable management devices; and 
         FIG. 19  is a rear perspective view depicting yet another example configuration of interface devices and cable management devices. 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to  FIGS. 2-7 , an example fiber distribution hub (FDH)  200  in accordance with the principles of the present disclosure is shown. The FDH  200  includes a cabinet  201  that houses internal components. The cabinet  201  includes openings through which a feeder cable (e.g., or F 1  cable)  700  and a subscriber cable  708  enter and exit the cabinet  201  (see  FIG. 2C ). A swing frame  300  is pivotably mounted on hinges  355  within the cabinet  201 . The swing frame  300  includes bulkhead  301  that divides the swing frame  300  into a front portion  302  (see  FIG. 4 ) and a back portion  304  (see  FIG. 2C ). The bulkhead  301  includes a main panel  310  having a termination region  311  and a storage region  313 . Generally, at least one termination module  400  (see  FIGS. 13A and 13B ) is provided at the termination region  311  and at least one storage module  600  (see  FIG. 9 ) is provided at the storage region  313 . In some embodiments, the bulkhead  301  also includes a secondary panel  315  positioned adjacent the main panel  310  and configured for cable management. One or more feeder cable interfaces  800  can be positioned within the rear portion of the swing frame  300 . At least one splitter module housing  322  accommodating one or more splitter modules  500  is positioned at the top of the swing frame  300 . 
       FIG. 3  is a schematic diagram showing an example cable routing scheme for the FDH  200 . The FDH  200  generally administers connections at a termination panel between incoming fiber and outgoing fiber in an Outside Plant (OSP) environment. As the term is used herein, “a connection” between fibers includes both direct and indirect connections. Examples of incoming fibers include the feeder cable fibers that enter the cabinet and intermediate fibers (e.g., connectorized pigtails extending from splitters and patching fibers/jumpers) that connect the feeder cable fiber to the termination panel. Examples of outgoing fibers include the subscriber cable fibers that exit the cabinet and any intermediate fibers that connect the subscriber cable fibers to the termination panel. The FDH  200  provides an interconnect interface for optical transmission signals at a location in the network where operational access and reconfiguration are desired. For example, as noted above, the FDH  200  can be used to split the feeder cables and terminate the split feeder cables to distribution cables routed to subscriber locations. In addition, the FDH  200  is designed to accommodate a range of alternative sizes and fiber counts and support factory installation of pigtails, fanouts and splitters. 
     As shown at  FIG. 3 , a feeder cable  700  is initially routed into the FDH  200  through the cabinet  201  (e.g., typically through the back or bottom of the cabinet  201  as shown in  FIG. 2C ). In certain embodiments, the fibers of the feeder cable  700  can include ribbon fibers. An example feeder cable  700  may include twelve to forty-eight individual fibers connected to a service provider central office  101 . In some embodiments, after entering the cabinet  201 , the fibers of the feeder cable  700  are routed to a feeder cable interface  800  (e.g., fiber optic adapter modules, a splice tray, etc.). At the feeder cable interface  800 , one or more of the fibers of the feeder cable  700  are individually connected to separate splitter input fibers  702 . The splitter input fibers  702  are routed from the feeder cable interface  800  to the splitter module housing  322 . At the splitter module housing  322 , the splitter input fibers  702  are connected to separate splitter modules  500 , wherein the input fibers  702  are each split into multiple pigtails  704 , each having connectorized ends  706 . In other embodiments, however, the fibers of the feeder cable  700  can be connectorized and can be routed directly to the splitter modules  500  thereby bypassing or eliminating the need for an intermediate feeder cable interface  800 . 
     When the pigtails  704  are not in service, the connectorized ends  706  can be temporarily stored on a storage module  600  that is mounted at the storage region  313  of the swing frame  300 . When the pigtails  704  are needed for service, the pigtails  704  are routed from the splitter modules  500  to a termination module  400  that is provided at the termination region  311  of the swing frame  300 . At the termination module  400 , the pigtails  704  are connected to the fibers of a distribution cable  708 . The termination panel is the dividing line between the incoming fibers and the outgoing fibers. A typical distribution cable  708  forms the F 2  portion of a network (see  FIG. 1 ) and typically includes a plurality of fibers (e.g., 144, 216 or 432 fibers) that are routed from the FDH  200  to subscriber locations  709 . 
     In some embodiments, one or more of the fibers of the feeder cable  700  are not connected to any of the splitter modules  500 . Rather, these fibers of the feeder cable  700  are connected to pass-through fibers  712  having connectorized ends  714 . The pass-through fibers  712  are connected to the termination modules  400 , without first connecting to the splitter modules  500 . By refraining from splitting a fiber  712 , a stronger signal can be sent to one of the subscribers. The connectorized ends  714  of the pass-through fibers  712  can be stored at the storage region  313  when not in use. 
     Referring back to  FIGS. 2A-2C , the cabinet  201  of the FDH  200  includes a top panel  202 , a bottom panel  203 , a right side panel  204 , a left side panel  206 , a back panel  205 , and at least one front door. In some embodiments, the at least one front door includes a right door  210  and a left door  212 . In one embodiment, the front doors  210 ,  212  include a lock  211 . The at least one front door is pivotally mounted to the cabinet  201  using hinges  214 ,  216  to facilitate access to the components mounted within the cabinet  201 . 
     In general, the cabinet  201  of the FDH  200  is configured to protect the internal components against rain, wind, dust, rodents and other contaminants. However, the cabinet  201  remains relatively lightweight for easy installation, and breathable to prevent accumulation of moisture in the unit. In some embodiments, an aluminum construction with a heavy powder coat finish also provides for corrosion resistance. In one example embodiment, the cabinet  201  is manufactured from heavy gauge aluminum and is NEMA-4X rated. In other embodiments, however, other materials can also be used. 
     In accordance with example embodiments, the FDH  200  is provided in pole mount or pedestal mount configurations. For example, as shown in  FIG. 2 , loops  218  can be provided on the cabinet  201  for facilitating deployment of the cabinet  201  at a desired location. The loops  218  can be used to position the cabinet using a crane. In particular, the crane can lower the cabinet  201  into an underground region. In some embodiments, the loops  218  are removable or can be adjusted to not protrude from the top cabinet panel  202 . 
     Still referring to  FIGS. 2B-2C , the swing frame  300  of the FDH  200  includes a top panel  320 , a bottom panel  330 , a right side panel  340 , and a left side  341 . A hinge-mounting strip  350  is positioned at the left side  341  of the swing frame  300 . As depicted at  FIG. 4 , the bulkhead  301  further includes a connecting panel  319  that connects the main panel  310  to the hinge-mounting strip  350 . As shown best at  FIG. 4 , a portion  325  of the secondary panel  315  extends upwardly past the top panel  320  of the swing frame  300 . The bulkhead  301  extends vertically between the top and bottom panels  320 ,  330 , and laterally between the right side panel  340  and the left side  341 . 
     In some embodiments, the hinge-mounting strip  350  of the swing frame  300  is mounted to the cabinet  201  of the FDH  200  using one or more hinges  355 . The hinges  355  enable the entirety of the swing frame  300 , including the termination modules  400 , the storage modules  600 , the feeder cable interface device  800 , and the splitter modules  500 , to be swung out of the front doors  210 ,  212  of the cabinet  201  to enable access to optical components in the rear portion  304  of the swing frame  300  for cleaning, testing, maintenance, additions, etc. Pivoting the swing frame  300  out of the cabinet  201  causes the right side panel  340  of the swing frame  300  to move away from the interior volume of the cabinet  201 . In some example embodiments, the swing frame  300  can be pivoted ninety degrees or more out of the cabinet  201 . 
     In some embodiments, the hinges  355  of the swing frame  300  are positioned to provide a single point of flex for the fiber cable routed to the swing frame  300 . This hinge point is constructed to control the fiber bend. In particular, the hinges  355  and cable management devices, which are discussed in greater detail herein, are designed to ensure that manufacture recommended bend radii are maintained when the swing frame  300  is opened or closed. In one embodiment, the cabinet  201  can be configured at a factory, or plant, so as to have cable bundles dressed around the hinges  355 . Preconfiguring the cabinet  201  reduces the chance that cabling will be done incorrectly. 
     When the swing frame  300  is in the open position, as shown in  FIG. 2C , components in the rear portion  304  of the swing frame  300  are accessible. For example, a rear side of the main panel  310  and a rear side of the secondary panel  315  are accessible. In addition, the splitter modules  500  located in the splitter module housing  322  (see  FIG. 4 ) are accessible through the open top of the swing frame  300  when the swing frame  300  is swung out of the cabinet  201 . In contrast, when the swing frame  300  is in the closed position (see  FIG. 2B ), only components on the front portion  302  of the swing frame  300  are readily accessible. 
     In example embodiments, the swing frame  300  includes a release latch (not shown) that locks the swing frame  300  in a closed position within the cabinet  201  of the FDH  200  until the latch is actuated. Once the latch is actuated, the swing frame  300  can be pivoted out of the cabinet  201 . In addition, a pivoting locking member (not shown) can be mounted to rear side  304  of the swing frame  300  to hold the swing frame  300  in the open position. 
     Referring to  FIGS. 4-5 , the storage region  313  of the swing frame  300  is located below the termination region  311 . In other embodiments, however, the storage region  313  can be above or adjacent to the termination region  311 . In general, the termination region  311  defines at least one rectangular opening  312  through which adapters  450  (see  FIGS. 13A-13B ) from a termination module  400  extend. The termination modules  400  are described in greater detail herein. In the embodiment shown in  FIG. 4 , the termination region  311  includes two columns of openings  312  with each column including twelve elongated slots. Strips  309  separate the openings  312  of each column and provide surface area for adhering labeling information (e.g., connector designation). The storage region  313  also defines one or more openings  314  into which storage modules  600  (see  FIG. 9 ) are mounted. The storage modules  600  are described in greater detail herein. 
     The bulkhead  301  bifurcates the bottom panel  330  into a front portion  331  (see  FIG. 4 ) and a rear portion  336  (see  FIGS. 2C and 14 ). In general, the front portion  331  of the bottom panel  330  projects forwardly from the bulkhead  301 . In some embodiments, the front portion  331  is further divided into a first front portion  332  and a second front portion  334 . Each front portion  332 ,  334  includes a flange  333 ,  335 , respectively, that protrudes substantially perpendicular from the bottom panel  330 . The front portion  331  of the bottom panel  330  thereby forms a trough configured to retain slack or excess fiber from the storage region  313  or from the secondary panel  315 . Edge  337  of the first front portion  332  is angled to allow the swing frame  300  to pivot open without interference from the trough. 
     As best shown in  FIGS. 4 and 6 , the bulkhead divides the side panel  340  into front and rear flanges  342 ,  344 , respectively. The front flange  342  extends forwardly from the secondary panel  315  and the rear flange  344  extends rearwardly from the secondary panel  315 . The rear flange  344  extends from the bottom panel  330  to a bend limiter  962  extending from the top panel  320 . The front flange  342  extends from the bottom panel  330  past the top panel  320  to the protruding portion  325  of the secondary panel  315 . In some embodiments, the front flange  342  includes a forward portion  344  substantially parallel to the rear flange  344  and an angled portion  343  extending between the protruding portion  325  of the secondary panel  315  and the forward portion  344 . 
     As best shown in  FIG. 7 , the top panel  320  of the swing frame  300  is substantially rectangular. The top panel  320  includes front and back edges  326 ,  327 . Flanges  323 ,  324  (see  FIG. 4 ) protrude upward from the edges  326 ,  327 , respectively. 
     The top panel  320  also has a first end  328  adjacent side  341  and a second, opposite end  329  adjacent the side panel  340 . A bend radius limiter  940  extends upward from the first end  328 . In some embodiments, a portion of the end  329  of the top panel  320  defines a width of a channel B with the front flange  342  of the side panel  340 . The portion of the end  329  defining the channel B terminates before reaching the remaining portion of the end  329 . The depth of the channel B extends from the secondary panel  315  to the flange  335  of the second front portion  33  of the bottom panel  330 . 
     The splitter module housing  322  of the FDH  200  is positioned on the top panel  320  adjacent the first end  328 . The splitter module housing  322  serves to protect, organize, and secure the splitter modules  500  of the FDH  200 . The splitter module housing  322  can be constructed in various sizes to accommodate different numbers of splitter modules  500 . The splitter module housing  322  is generally rectangular and defines one or more locations within the open interior sized to accept one or more optical splitter modules  500 . To accommodate the splitter modules  500 , the module housing  322  includes structure for supporting/securing the splitter modules  500 . In example embodiments, the splitter modules  500  are designed to snap into the splitter module housing  322 . In one embodiment, the splitter modules  500  are loaded into the splitter module housing  322  from front to back (i.e., from the side facing end  329  to the side facing end  328 ). The module housing  322  is further configured to enable the splitter modules  500  to receive an input fiber, such as fiber  702  of  FIG. 3 , on one end of the splitter module  500  and to output multiple fibers, such as pigtails  704  of  FIG. 3 , from the opposing end of the splitter  500 . 
     Referring now to  FIGS. 8A-8C , one type of splitter module  500  that can be mounted in the splitter module housing  322  is a splitter having an integral connector.  FIG. 8A  is a left side view of such a splitter module  500 . The splitter module  500  includes a housing  505  having at least one protective boot  510  protruding frontwardly and at least one integral connector  520  protruding rearwardly. In the embodiment shown, two boots  510  protrude from the front and two integral connectors  520  protrude rearwardly from the splitter housing  505 . In one example embodiment (not shown), each splitter has four integral connectors  520 . In some embodiments, a handle  540  also protrudes from the front end of the splitter housing  505 .  FIG. 8B  is an exploded view of the splitter module  500  of  FIG. 8A  showing the internal components of the splitter module  500 . 
       FIG. 8C  shows a cross-section of the splitter module  500  of  FIG. 7A  inserted in the splitter module housing  322 . An adapter assembly  530  is secured to the splitter module housing  322  using a fastener  536 . In one embodiment, adapter assemblies  530  are mounted at the backside of the splitter module housing  322 . The adapter assembly  530  is configured to receive the connectors  520  of the splitter module  500  when the splitter module  500  is inserted into the splitter module housing  322 . As shown, the adapter assembly  530  is further configured to receive an opposing connector associated with the feeder cable  700 . In some embodiments, the adapter assembly  530  receives a connector  703  terminating a splitter input fiber  702 . In other embodiments, the adapter assembly  530  receives a connector  701  terminating the feeder cable  700  itself. In this way, the feeder cable fibers  700  can be readily coupled to the splitter modules  500 . 
     Other embodiments of splitter modules  500  do not include integral connectors  520 . In such embodiments, adapter assemblies  530  are not mounted at the splitter module housing  322  and the feeder cables  700  cannot be plugged directly into the splitter modules  500 . Rather, input pigtails (not shown) pass through the splitter housing  505  and enter the splitter module  500 . The opposing ends of the input pigtails can be connectorized or unconnectorized. If the ends  701  terminate in connectors (not shown), then the input fibers  702  are interfaced with the feeder cable  700  using an adapter module  810  (see  FIG. 18 ). If the ends  701  are unconnectorized, then the input fibers  702  are spliced with the feeder cable  700  using a splice tray  808  (see  FIG. 19 ). 
     Typically, each splitter module  500  receives between one and four fibers and outputs between two and sixteen fibers  704  for every input fiber. In one example embodiment, four input fibers  702  enter a splitter module  500  and thirty-two pigtail fibers  704  exit the splitter module  500 . Further information regarding the splitter module  500  can be found in the U.S. application Ser. No. 11/354,297, entitled “Fiber Optic Splitter Module,” that was filed on a date concurrent herewith, and which is hereby incorporated by reference. Additional information on other types of splitter modules can be found at U.S. application Ser. No. 10/980,978, filed Nov. 3, 2004, entitled “Fiber Optic Module And System Including Rear Connectors;” U.S. application Ser. No. 11/138,063, filed May 25, 2005, entitled “Fiber Optic Splitter Module;” U.S. application Ser. No. 11/215,837, filed Aug. 29, 2005, entitled “Fiber Optic Splitter Module With Connector Access;” and U.S. application Ser. No. 11/321,696, filed Dec. 28, 2005, entitled “Splitter Modules For Fiber Distribution Hubs,” the disclosures of which are hereby incorporated by reference. 
     Referring now to  FIGS. 9-10 , the splitter modules  500  and storage modules  600  can be incrementally added to the swing frame  300 .  FIG. 9  illustrates a splitter module  500  having multiple connectorized pigtails  704  exiting from a protective boot  510  on the splitter module  500 . The connectorized pigtails  704  are typically stored in one or more storage modules  600  prior to installation on the swing frame  300 . In some embodiments, the connector  706  of each pigtail  704  is secured in a storage module  600  before the splitter module  500  leaves the factory. Typically, the connectorized pigtails  704  of each splitter module  500  are routed to four storage modules  600  each holding eight connectors. 
     The storage module  600  includes a body  610  having a front side  602  and a rear side  604 . The body  610  is configured to hold at least one fiber connector  706 . Typically, the body  610  is configured to hold about eight connectors  706 . In some embodiments, the body  610  is arranged to retain the fiber connectors  706  in a single row configuration. In other embodiments, the body  610  can be arranged to hold the connectors  706  in a square pattern or in any other desired configuration. More information regarding the storage modules  600  can be found in U.S. application Ser. No. 10/610,325, filed on Jun. 30, 2003, entitled “Fiber Optic Connector Holder and Method;” U.S. application Ser. No. 10/613,764, filed on Jul. 2, 2003, entitled “Telecommunications Connection Cabinet;” and U.S. application Ser. No. 10/871,555, filed on Jun. 18, 2004, entitled “Multi-position Fiber Optic Connector Holder and Method,” the disclosures of which are hereby incorporated by reference. 
     In some embodiments, the body  610  is designed to snap into one of the openings  314  defined in the storage region  313  of the main panel  310 . The openings  314  can be arranged in any desired configuration within the storage region  313  of the main panel  310 . In the example shown in  FIG. 10 , the storage region  313  of the main panel  310  defines nine openings  314  in a rectangular pattern. Each opening  314  is configured to receive a storage module body  610  arranged to retain eight fiber connectors  706  in a row. 
     As shown in  FIG. 10 , when the splitter module  500  is loaded into the splitter module housing  322  during installation, the corresponding storage modules  600  are loaded onto the storage region  313  of the main panel  310 . For ease in viewing, only one splitter  500  having one pigtail  704  and one storage module  600  is illustrated. The pigtail  704  extending from the splitter module  500  to the storage module  600  is routed from the protective boot  510 , across the top panel  320 , down through the channel B on the front side of the secondary panel  315 , and across the bottom panel  330  of the swing frame  300 . 
     To accomplish this routing, the top panel  320  and secondary panel  315  include cable management arrangements. In some embodiments, the cable management arrangements on the top panel  320  include a first spool  952  positioned between the splitter housing  322  and the bend radius limiter  962  and a second spool  954  positioned between the bend limiter  940  and the front flange  342 . Pigtails  704  output from the splitter  500  are first wrapped around the first spool  952  and then around the second spool  954 . 
     A bend radius limiter  964  having tabs  965  and extending downward from the top panel  320  partially defines the channel B. From the second spool  954 , some of the pigtails  704  are routed over the bend limiter  964  and into the channel B. In some embodiments, a partial fiber spool  966  is mounted to extend from the protruding portion  325  of the secondary panel  315  and is also oriented to route fiber into the channel B. To avoid excessive weight or entanglement of the fibers  704 , some of the fibers  704  can be routed into channel B over the partial spool  966  instead of bend limiter  964 . Extra slack can also be taken up by routing the pigtails  704  over spool  966  instead of over bend limiter  964 . A bend limiter  968  can also be mounted on the protruding portion  325  of the secondary panel  315  and oriented to route fiber up to the partial spool  966 . 
     The front of the secondary panel  315  includes at least one row of partial spools  970  and at least one row of radius limiters  980 . In one example embodiment, the partial spools  970  are oriented to enable fiber routed down channel B to wrap at least partially around one of the spools  970 . The fiber can travel from the partial spools  970  either along the bottom panel  330  to the storage modules  600  or over the limiters  980  to the termination modules  400 . The limiters  980  are oriented to enable fiber routed from the partial spools  970  to travel to the termination modules  400  without excessive bending. 
     Referring now to  FIG. 11 , when a pigtail  704  retained in a storage module  600  should be connected to a subscriber distribution line  708 , the corresponding connector  706  is removed from the storage module  600  and transferred to the appropriate adapter  450  on a termination module  400 . During this transfer process, the fiber may need to be rewound around a different partial spool  970 , such as partial spool  972 , in order to reach the adapter  450 . From the partial spool  972 , the fiber can be routed around a suitable limiter  980  to avoid excessive bending before reaching the adapter  450 . In some embodiments, the fiber is also fed through support fingers  990  extending from the termination section  311  of the main panel  310  before plugging into the adapter  450 . When all of the fibers  704  originally secured in the storage module  600  have been routed to subscriber termination modules  400 , the empty storage modules  600  can be removed to make room for a new splitter module  500  and new storage modules  600 . 
     Referring now to  FIGS. 12A-12B , as time passes and the number of subscribers increases, a user can add termination modules  400  to the swing frame  300 .  FIGS. 12A and 12B  show one example of a termination module  400 . The termination module  400  includes a termination leg  410  and a management leg  420  arranged in a substantially L-shaped configuration. In some embodiments, a linking section  430  connects the termination leg  410  to the management leg  420 . In other embodiments, the linking section  430  is monolithically formed with either the termination leg  410  or the management leg  420 . In still other embodiments, the termination leg  410 , the management leg  420 , and the linking section  430  are monolithically formed (e.g., are constructed as a single piece of bent sheet metal). 
     In some embodiments, a front side of the termination leg  410  of the termination module  400  (shown in  FIG. 12B ) mounts to the rear side of the main panel  310 . In one embodiment, the termination leg  410  mounts to the main panel  310  using screws  417 . In other embodiments, however, other fasteners such as bolts, rivets, nails, and other such devices can be used to connect the module  400  to the main panel  310 . In still other embodiments, the module  400  can be attached to the main panel  310  using adhesive. 
     Each termination module  400  includes at least one row of fiber optic adapters  450  for connecting the fibers of the main cable  700  to the fibers of the distribution cable  708 . Each adapter  450  has a front end  452  and a rear end  454 . The front end  452  of each adapter  450  is configured to retain a connector  714  of a fiber  712  interfaced with the main line  700 , or the connector  706  of a fiber  704  split from the main line  700 . The rear end  454  of each adapter  450  is configured to retain a connector  710  of a fiber of the distribution cable  708 . The adapters  450  protrude through the termination leg  410  so that the connectors  706  enter the front ends  452  of the adapters  450  from a front side of the main panel  310  and the connectors  710  of the distribution cable  708  enter the adapters  450  from a rear side of the main panel  310 . 
     In the depicted embodiment, each module  400  includes six horizontal rows of adapters  450  that cooperate to define two side-by-side banks of adapters. When the module  400  is mounted to the main panel  310 , the front side of the leg  410  abuts against the backside of the main panel  310 , and the rows of adapters  450  project forwardly through the corresponding horizontal slots  314  defined by the panel  310 . 
     The management leg  420  extends rearwardly from the termination leg  410 . Each management leg  420  includes an appropriate number of fanouts  424  to accommodate the number of adapters  450  on the module  400 . For example, in one embodiment, the termination leg  410  of a module  400  includes six rows of adapters  450 , each row having twelve adapters  450 , and the management leg  420  includes six 12:1 fanouts  424 . As the term is used herein, a 12:1 fanout is a fanout configured to receive twelve optical fibers and to output a single cable ribbon containing the twelve fibers. In another embodiment, nine 8:1 fanouts or three 24:1 fanouts could be provided instead of the 12:1 fanouts. In still other embodiments, fanouts can be used to upjacket the fiber. 
     In some embodiments, the termination module  400  is precabled at the factory to include a connectorized distribution fiber  708  coupled to each adapter  450 . Dust caps  453  are generally provided on the front ends  452  of the adapters  450  to protect the terminated distribution fibers  708  from dust, dirt, and other contaminants. The connector  710  of each distribution fiber  708  is mounted within the rear end  454  of an adapter  450  and the distribution fibers  708  are routed from the connector  710  to the fanouts  424  provided on the management leg  420  of the termination module  400 . In still other embodiments, the termination module  400  is not precabled and dust caps  455  are also provided on the rear ends  454  of the adapters  450  to protect the adapters  450 . 
     In some embodiments, the management leg  420  of the termination module  400  also includes at least one cable management device  425  for managing excess fiber length of the distribution fibers  708 . Generally, in such systems, the fibers  708  are routed first to the cable management device  425  and then to the fanouts  424 . Examples of cable management devices  425  include a fiber spool, one or more radius bend limiters, one or more fiber clips, and other such devices. In the example shown, the management leg  420  includes a fiber spool  426  formed from two radius bend limiters. Each radius bend limiter includes a flange  427  for retaining the fiber on the spool  426 . In some embodiments, one or more fiber cable clips  428  for retaining fiber cables can be spaced between the radius bend limiters of the spool  426 . 
     Referring now to  FIG. 13 , the management leg  420  of the termination module  400  includes an opening  422  through which the fibers are routed from the cable management devices  425  to the fanouts  424 . Upon exiting the fanouts  424 , the ribbon fibers are routed to a cabinet fanout (not shown) or other cable interface device. In other embodiments, the fanouts  424  are provided on the same side of the management leg  420  as the cable management device  425 . In such embodiments, the ribbon fibers are routed from the fanouts  424  through the openings  422  and to the cabinet fanout. The cabinet fanout is mounted to the interior of the cabinet  201  and is not attached to the swing frame  300 . The cabinet fanout can be used to reduce the ribbon fibers into a single jacketed stub cable that exits the FDH  200 . The stub cable is spliced to a subscriber distribution cable outside of the FDH  200 . In various embodiments, the stub cable ranges in length from about 25 feet to about 300 feet. In other embodiments, the distribution cable  708  can be routed into the cabinet  201  and spliced or otherwise connected to the fiber  708 . 
     Referring now to  FIG. 14 , the rear side  304  of the swing frame  300  forms an open chamber adapted to house at least one termination module  400 . The open chamber is defined by the bulkhead  301 , the top panel  320 , the bottom panel  330 , and the side panel  340 .  FIG. 14  is a rear perspective view of four termination modules  400  mounted in the open chamber. The adapters  450  have been removed for ease in viewing. In other embodiments, any desired number of termination modules  400  can be mounted on the swing frame  300 . The termination modules  400  are configured to mount to the rear side of the termination region  311  of the main panel  310 . 
       FIG. 15  shows a left side view of a swing frame  300  having four termination modules  400  mounted therein. When multiple termination modules  400  are mounted to the rear side of the main panel  310 , the management legs  420  of the termination modules  400  form a partial side panel opposing the side panel  340 . In some embodiments, the management legs  420  of the modules  400  are secured to one another or to the swing frame  300 . In other embodiments, shown in  FIG. 15 , the modules  400  are secured to the swing frame  300  only at the termination leg  410  and the management legs  420  are free floating. 
     Referring now to  FIGS. 16-19 , the swing frame  300  can be configured with different interface devices  800  (see  FIG. 3 ) and cable management devices to create multiple fiber pathways between the incoming feeder cable  700  and the distribution lines  708 . The interface devices  800  and management devices used in a particular configuration will depend on whether it is desirable to split the feeder cable  700  and what type of splitter module  500  is utilized. 
     In some embodiments, the feeder cable  700  connects to one or more splitter input fibers  702 . In one such embodiment, a first end  701  of a splitter input fiber  702  is connectorized. In another such embodiment, the first end  701  is unconnectorized. The opposite end  703  of the input fiber  702  can either interface with an integral connector  520  on the splitter module  500 , such as when using the splitter module depicted in  FIGS. 8A-8C , or can penetrate the splitter housing  505 . In other embodiments, however, the feeder cable  700  has connectors configured to interface with integral connectors  520  of the splitter module  500 . 
       FIG. 16  is a rear view of the swing frame  300  adapted to interface a connectorized feeder cable  700  with a splitter module  500 . To accomplish this interface, the cable management devices are arranged according to a configuration C 1 . In configuration C 1 , a cable storage spool  922  and one or more partial storage spools  924  are mounted to the side panel  340  of the swing frame  300 . A fanout device  926  is mounted adjacent the spools  922 ,  924 . A radius limiter  936  is mounted from the secondary panel near the corner formed by the top panel  320  and side panel  340 . Support fingers  932  projecting downward from the top panel  320  form a path A along which fibers can be routed from one end  329  of the top panel  320  to the other end  328 . In some embodiments, the support fingers  932  include a multi-pronged clip  934  having at least two fingers  932 , each finger  932  extending in a different direction. In one example embodiment, the multi-pronged clip  934  includes four fingers  932  positioned orthogonally relative to one another. Any excess fiber length can be taken up by winding the pigtails  702  around the multi-pronged clip  934 . A limiter  940  having tabs  945  extends from the top panel. 
     To connect the feeder cable  700  to the splitter  500 , the cable  700  is first routed around spools  922 ,  924  and then to the fanout device  926 . The fanout device  926  separates the fibers of the feeder cable  700  into individual input fibers. Any excess length of the individual fibers of the feeder cable  700  can be stored by wrapping the fibers around the spools  922 ,  924 . The fibers of the feeder cable  700  are next routed around the limiter  936  and along the path A using the support fingers  932  projecting downward from the top panel  320 . The feeder cable  700  is next curved around the limiter  940  extending from the top panel  320  and plugged directly into at least one of the adapter assemblies  530  secured to the splitter module housing  322 . The fibers of the feeder cable  700  can be protected while being routed within the swing frame  300  by loose buffer tubes. 
       FIG. 17  is a rear perspective view of the swing frame  300  adapted to interface a connectorized feeder cable  700  to a splitter module  500 . The cable management devices are arranged according to a variation of configuration C 1 . The storage spools  922 ,  924  and fanout device  926  are mounted to the rear side of the secondary panel  315  rather than the side panel  340 . In other embodiments (not shown), the storage spools  922 ,  924  and fanout device  926  could be mounted to the bottom panel  330 . Regardless of the location of the spools  922 ,  924  and fanout device  926 , the feeder cable  700  is still routed from the fanout device  926  to the bend limiter  936 , along path A, over the bend limiter  940  and to the adapter assembly  530  mounted on the splitter module housing  322 . 
     Referring now to  FIGS. 18-19 , the feeder cable  700  can be interfaced with splitter inputs  702  using at least one interface device  800  rather than connecting directly to the splitter  500 .  FIG. 18  is a rear perspective view of the swing frame  300  configured to interface a connectorized feeder cable  700  with a splitter module  500  through intermediate splitter input fibers  702 . Each splitter input fibers  702  has a first connectorized end  703  that plugs into one of the adapter assemblies  530  opposite the integral connectors  520  of the splitters  500 . In other embodiments not using a splitter having an integral connector, however, the splitter input  702  is a pigtail that penetrates the splitter housing  505  rather than plugging into an adapter assembly  530 . Each splitter input fibers  702  also has a second connectorized end  701  that interfaces with a connectorized end of a fiber of the feeder cable  700 . 
     Such input pigtails  702  are routed from the adapter assembly  530  over the bend radius limiter  940  and underneath the top panel  320  as shown in  FIG. 16 . In particular, the input pigtails  702  are routed along the path A towards the side panel  340  using the support fingers  932  and then around the radius bend limiter  936 . The ends  701  of the input pigtails are then connected to the feeder cable  700  using a first adapter module  820 . In some embodiments, the first adapter module is mounted to the secondary panel  315  adjacent the bottom panel  330 . In other embodiments, however, the first adapter module  820  can be secured to the bottom panel  330  or the side panel  340 . The first adapter module  820  includes multiple adapters  825  arranged in one or more rows. In some embodiments, each row includes about six adapters  825 . Additional information regarding the adapter module  820  can be found in U.S. application Ser. No. 11/095,033, filed Mar. 31, 2005, and entitled “Adapter Block Including Connector Storage;” and U.S. Pat. Nos. 5,497,444; 5,717,810; 5,758,003; and 6,591,051, the disclosures of which are hereby incorporated by reference. 
     In order to connect the feeder cable  700  to the first adapter module  820 , additional cable management devices are provided according to a second configuration C 2 . The second configuration C 2  includes a fanout device  901  and one or more full or partial slack storage fiber spools  902 ,  904 , respectively. In the example shown, the fanout device  901  and storage spools  902 ,  904  are mounted to the bottom panel  330 . 
     The feeder cable  700  is first routed to the fanout device  901 , which separates the fibers of the ribbon cable  700  into individual fibers. Any excess length of the individual fibers of the feeder cable  700  can be stored in the slack storage spool  902  and partial slack storage spools  904 . The fibers of the feeder cable  700  are next routed to the first adapter module  820 . The connectorized ends of the feeder cable  700  are mounted into one end of the adapters  825  of the first adapter module  820 . The connectorized ends  701  of the input fibers  702  are routed from the radius limiter  936  to the opposite end of the adapters  825  of the first adapter module  820 . The adapters  825  provide an interface between the connectors of the feeder cable fibers  700  and the connectors  701  of the input fibers  702 . 
       FIG. 19  is a rear perspective view of the swing frame  300  configured for use with a splitter module and a feeder cable  700  having unconnectorized ends. The feeder cable  700  is spliced to splitter input fibers  702  having unconnectorized second ends  701 . In order to connect the feeder cable  700  to the unconnectorized fiber inputs  702 , a splice tray  830  is provided at the rear side  304  of the swing frame  300 . 
     In order to connect the feeder cable  700  to the splice tray  830 , additional cable management devices are provided according to a third configuration C 3 . The third configuration C 3  includes a fanout device  907  and one or more radius bend limiters  906  mounted around the splice tray  830 . Additionally, at least one radius bend limiter  908  is positioned adjacent the splice tray  830 . Each limiter  906  includes a tab  907  to maintain the fibers in a loop around the limiters  906 . The limiters  906  are oriented to prevent fiber from catching on the corners of the splice tray  830 . In some embodiments, the splice tray  830  and limiters  906  are positioned on the back of the secondary panel  315 . In other embodiments, however, the splice tray  830  and limiters  906  can be positioned in any desired location at the rear side  304  of the swing frame  300 . 
     The unconnectorized ends of the feeder cable  700  are routed around the limiters  906  and to the splice tray  808 . Any excess length of the individual fibers of the feeder cable  700  can be stored by wrapping the fibers around the splice tray  830 . The input fibers  702  from the splitter module  500  are routed from the radius limiter  936  around the limiter  908  and into the splice tray  830 . The unconnectorized ends of the feeder cable  700  are then spliced with the unconnectorized ends  701  of the input fibers  702 . 
     Still referring to  FIGS. 16-19 , in some embodiments, it may be desirable not to split one or more of the feeder cables  700  to enable transmission of a stronger or more reliable signal to a subscriber. In some embodiments, therefore, the swing frame  300  is further configured to enable at least one fiber (referred to as a pass-through fiber)  712  to interface with a fiber from the feeder cable  700 . The pass-through fiber  712  bypasses the splitter modules  500  and proceeds to the front of the swing frame  300  to interface with a distribution line  708 . 
     To accomplish such a routing, the swing frame  300  includes an opening  910  in the rear flange  344  of the side panel  340 . In some embodiments, the opening  910  includes a radius limiter  912  (best seen in  FIG. 13 ) extending outward from the outside surface of flange  344  to prevent excessive bending of a fiber routed through the opening  910 . A tab  915  can also be pressed outward in rear flange  344  to define a channel up the outer side of the rear flange  344 . A radius bend limiter  962  links the rear flange  344  of the side panel  340  to the top panel  320 . Additional cable management devices are provided based on the configuration C 1 , C 2 , C 3  with which the swing frame  300  is set up. 
     Referring to  FIG. 17 , if the swing frame  300  is arranged according to configuration C 1 , then the connectorized fibers of the feeder cable  700  are connected to the input fibers  702  using a second adapter module  810 . The adapter module  810  includes multiple fiber optic adapters  815  configured to accept connectorized fibers from either end. The swing frame  300  also includes additional cable management in the form of a bend radius limiter  906  and slack storage spools  902 ,  904 . 
     To bypassing the splitter modules  500 , the feeder cable  700  is still routed around spools  922 ,  924  to the fanout device  926 . From the fanout device  926 , however, the feeder cable fibers  700  are routed back around spools  922 ,  924 , around bend limiter  926  and then around spools  902 ,  904 . From the spools  902 ,  904 , the connectorized ends of the fibers  700  are secured to the adapter module  810 . The adapter module  810  connects the fibers  700  with connectorized ends of pass-through fibers  712  that are routed out the opening  910 , up the side panel  340 , over the limiter  962 , and onto the top panel  320 . From the top panel  320 , the pass-through fibers  712  are routed towards the termination modules  400  as described above with reference to  FIGS. 10 and 11 . 
     Referring to  FIG. 18 , pass-through fibers  712  can also be used with the second configuration C 2 . The feeder cable  700  is still routed first to the fanout device  901  and then to one end of the adapter module  820  with any slack being stored in spools  902 ,  904 . However, instead of splitter pigtails  702  connecting to the other end of the adapter module  820 , the pass-through pigtails  712  are plugged into the adapter module  820 . The pass-through pigtails  712  then follow the same routing pattern as discussed in the previous paragraph. 
     Referring to  FIG. 19 , the pass-through pigtails  712  can also be spliced to unconnectorized ends of the feeder cable  700 . If such a configuration is desired, then the swing frame  300  is provided with the second adapter module  810  discussed above with reference to  FIG. 17 . The feeder cable  700  is still routed around limiters  906  and up to the splice tray  830  according to the configuration C 3 . Any excess length of the individual fibers of the feeder cable  700  can be stored by wrapping the fibers around the limiters  906 . However, the fibers of the feeder cable  700  are spliced to connectorized pigtails  711  rather than to the splitter inputs  702 . From the splice tray  830 , the connectorized pigtails  711  are routed around the storage spools  902 ,  904  and then plugged into the second adapter module  810 . The second adapter module  810  connects the pigtails  711  with the pass-through connectorized fibers  712  that are routed out of the opening  910 , up the side panel  340  to the limiter  962 , and onto the top panel  320 . 
     The pass-through fibers  712  bypass the splitter module  500  and are routed around the second fiber spool  954  of the top panel  320  and into the channel B via either the limiter  964  or the partial spool  966 . The routing of the pass-through fiber  712  along the front side  302  of the swing frame is substantially the same as the routing of the splitter pigtails  704  discussed above with reference to  FIGS. 10 and 11 . Typically, a pass-through fiber  712  is immediately connected to a subscriber line  708  via an adapter  450  on a termination module  400 . In some embodiments, however, the pass-through fibers  712  can be stored in empty locations on the storage modules  600 . 
     The above specification, examples and data provide a complete description of the manufacture and use of the composition of the invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.