Abstract:
One embodiment disclosed relates to a manufactured multi-fiber cable for optical systems. The multi-fiber cable is manufactured to include a plurality of individual fiber cables, each individual fiber cable including a single optical fiber surrounded by a protective covering. There is a main cable hose around the individual fiber cables, and there is a connector on each end of each individual fiber cable. The individual fiber cables in the multi-fiber cable are preconfigured to be visually distinct from each other. Other embodiments are also disclosed.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to fiber optics, including fiber optics used in Fiber Channel interconnections and other interconnections.  
         [0003]     2. Description of the Background Art  
         [0004]     Optical fibers are used in various systems. For example, Fiber Channel systems use optical fibers. The Fiber Channel standard was developed and adopted by the American National Standard for Information Systems (ANSI). Briefly, Fiber Channel is a switched protocol that allows concurrent communication among servers, workstations, and various peripherals.  
         [0005]      FIG. 1  depicts a block diagram of a representative Fiber Channel architecture. A Fiber Channel network  100  is presented. Systems such as a workstation  120  and servers  122  are interconnected with various subsystems (for example, a tape subsystem  126 , a disk subsystem  128 , and a display subsystem  130 ) via a Fiber Channel fabric  110 .  
         [0006]     The Fiber Channel fabric  110  is a system that interconnects various node ports (N_ports) attached to the fabric  110 . The fabric  110  receives frames of data from a source node port and, using a Fiber Channel protocol, route the frames to a destination node port. In a preferred embodiment, the first protocol is the Fiber Channel protocol. Similar protocols, such as the asynchronous transfer mode (ATM), may be used in other similar embodiments.  
         [0007]     Each of the various systems (for example, server  122 ) and subsystems (for example, disk subsystem  128 ) connected to the Fiber Channel fabric  110  includes an associated node port  140 . Each node port comprises a hardware communication device at the node end of a link.  
         [0008]     The fabric ports (F_ports)  142  are access points of the fabric  110  for physically connecting the various node ports  140 . The fabric  110  has the capability of routing data frames based upon information contained within the frames as specified by a class of service. The node port  140  typically manages the point-to-point connection between itself and the fabric  110 .  
         [0009]     Interconnections between the node ports  140  and fabric ports  142  typically include fiber optic cables. As the use of fiber optics has grown in Fiber Channel systems and other systems, a need for fiber management techniques has arisen.  
         [0010]     It is desirable to improve the management of fiber optics used in Fiber Channel systems and in other systems.  
       SUMMARY  
       [0011]     One embodiment of the invention pertains to a manufactured multi-fiber cable for optical systems. The multi-fiber cable is manufactured to include a plurality of individual fiber cables, each individual fiber cable including a single optical fiber surrounded by a protective covering. There is a main cable hose around the individual fiber cables, and there is a connector on each end of each individual fiber cable. The individual fiber cables in the multi-fiber cable are preconfigured to be visually distinct from each other.  
         [0012]     Another embodiment pertains to a manufactured multi-fiber cable for Fiber Channel systems that includes a plurality of individual fiber cables, a main cable hose around the individual fiber cables, a protective reinforcement along the main cable hose, a connector on each end of each individual fiber cable, labels that are thermally attached to each end of the individual fiber cables during manufacture of the multi-fiber cable, and labels that are thermally attached to each end of the main cable hose during manufacture of the multi-fiber cable. Distinctive colors are used on the coverings of the individual fiber cables so as to provide said visual distinctness between the individual fiber cables of the multi-fiber cable. The individual fiber cables each comprise a single optical fiber surrounded by a covering, and the individual fiber cables extend outward past the main cable hose by less than one meter. Each connector comprises a precision ceramic ferrule.  
         [0013]     Another embodiment of the invention pertains to a Fiber Channel system. The system comprises a fiber channel fabric, including a plurality of fabric ports, and a plurality of node systems, each node system including a node port. The system further comprises a multi-fiber. The multi-fiber cable includes individual fiber cables. Each individual fiber cable connects a node port to a fabric port.  
         [0014]     Other embodiments of the invention are also disclosed. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]      FIG. 1  depicts a block diagram of a representative Fiber Channel architecture.  
         [0016]      FIG. 2  is a schematic diagram illustrating a multi-fiber cable for efficient manageability in accordance with an embodiment of the invention.  
         [0017]      FIG. 3  is a schematic diagram illustrating a multi-fiber cable for efficient manageability with a protective reinforcement in accordance with an embodiment of the invention.  
         [0018]      FIG. 4  is a schematic diagram illustrating a multi-fiber cable for efficient manageability with protective reinforcement and a spare fiber cable in accordance with an embodiment of the invention. 
     
    
     DETAILED DESCRIPTION  
       [0019]     Disadvantages and Difficulties with Conventional Techniques  
         [0020]     The management of optical fibers presents concerns than were not faced in conventional copper wire systems. For example, consider the management of the multitude of single optical fibers in a typical Fiber Channel system.  
         [0021]     A first concern is that optical fibers require significantly greater care than do copper wires, as they cannot be bent sharply, crimped, or twisted. Since optical fibers and their assemblies tend to be expensive, it is desirable to avoid damage to the optical fibers during system installation and maintenance.  
         [0022]     A second concern is that determining or verifying identification of individual optical fibers is considerably more difficult than for copper wires. With copper wires, the correspondence between wires at the ends of a long cable may be readily verified, for example, by shorting two wires at one end and checking for connectivity at the other end, or by using inexpensive testing devices. On the other hand, verifying the correspondence between optical fibers at the ends of an optical cable require more complex and expensive test equipment.  
         [0023]     For example, today in data centers, numerous single fiber cables are typically used between a server and a Fiber Channel switch (or storage array). A typical set-up may require 100 to 350 single fiber cables. These cables need to be laid very carefully into a raised floor or in overhead trays. During the lay process, the cables are vulnerable to be damaged. In addition, the ends of the individual fiber cables conventionally require laborious manual identification and manual labeling. Debugging errors due to incorrect connections are painstaking.  
         [0024]     Solutions Provided by the Present Disclosure  
         [0025]     The present disclosure provides solutions to the above-discussed problems. By using the multi-fiber cable configured as disclosed herein, labor to lay the fiber cables is minimized. Hence, higher quality work is achievable at a faster rate when laying the fiber cables.  
         [0026]     Specific Embodiments  
         [0027]     In accordance with an embodiment of the invention, a multi-fiber (multi-string) Fiber Channel cable is disclosed. The multi-fiber Fiber Channel cable may be implemented with two, four, six, eight, or sixteen individual fiber cables per multi-fiber cable. The multiple individual fiber cables are tied together and configured together within a hose to form the multi-fiber cable.  
         [0028]      FIG. 2  is a schematic diagram illustrating a multi-fiber cable  200  for efficient manageability in accordance with an embodiment of the invention. The particular cable depicted in  FIG. 2  is a four-fiber cable. However, as mentioned above, other multi-fiber cables implemented in accordance with an embodiment of the invention may include other numbers of fibers, such two, four, six, eight, or sixteen individual fiber cables per multi-fiber cable.  
         [0029]     The multi-fiber cables are preferably formed in standard lengths. For example, the standard lengths may be two meters, five meters, ten meters, fifteen meters, thirty meters, and one hundred meters. Other standard lengths are possible.  
         [0030]     The ends of each individual fiber cable  202  of the multi-fiber cable  200  are configured to extend outside the hose (or wrap or coat)  206  of the main multi-fiber cable  200 . Each end of an individual fiber cable  202  is further pre-configured with a connector  204 . In a preferred embodiment, the connector  204  is a precision ceramic ferrule, such as an LC connector or an SC connector.  
         [0031]     Each individual fiber cable  202  is preferably coated with a protective coating of a unique color and/or pattern. In other words, each individual fiber cable  202  in the multi-fiber cable is individually identifiable by the color and/or the pattern of its outer coating.  
         [0032]     In a preferred embodiment, the multi-fiber cable  200  may be constructed with a main label  208  on each end. In addition, each individual (independent) cable  202  may also be constructed with an individual fiber label  210 . The labels may be attached, for example, using a thermal transfer process, and the attachment may be performed using an automated label applicator machine.  
         [0033]      FIG. 3  is a schematic diagram illustrating a multi-fiber cable  300  for efficient manageability with a protective reinforcement in accordance with an embodiment of the invention. The embodiment shown in  FIG. 3  is again a 4-fiber cable, but other embodiments would have other numbers of individual cables.  
         [0034]     The difference between the multi-fiber cable  300  in  FIG. 3  and the multi-fiber cable  200  in  FIG. 2  is that an additional protective reinforcement is added. As illustrated, the protective reinforcement may comprise, for example, a metal spiral  302 . The metal spiral  302  is depicted as implemented on the outside of the main cable hose  206 , but may also be implemented on the inside or embedded within the main cable hose  206 .  
         [0035]     Advantageously, the protective reinforcement further prevents damage from external forces. For example, the metal spiral  302  may prevent damage from a person stepping on the cable  300  with his or her foot. As another example, the metal spiral  302  may prevent damage from a person strongly bending the cable  300  by limiting the amount of bend inflicted on the cable  300 .  
         [0036]      FIG. 4  is a schematic diagram illustrating a multi-fiber cable  400  for efficient manageability with protective reinforcement and a spare fiber cable  402  in accordance with an embodiment of the invention. The embodiment shown in  FIG. 4  is again a 4-fiber cable, but other embodiments would be designed for other numbers of individual cables.  
         [0037]     The difference between the multi-fiber cable  400  in  FIG. 4  and the multi-fiber cable  300  in  FIG. 3  is that the spare (redundant) fiber cable  402  is added. The spare fiber cable  402  may be conveniently used to make a connection in case one of the other cables (or one of the connectors) has a fault or breaks. The spare cable  402  may also be used if need for an additional connection arises.  
         [0038]     Advantages  
         [0039]     The present application discloses a multi-fiber cable for efficient manageability of Fiber Channel or other systems. There are various advantages of using the multi-fiber cable as disclosed herein.  
         [0040]     First, compared with the conventional technique of laying hundreds of individual cable fibers, using the multi-fiber cables substantially reduces the number of (main) cables to lay. This advantageously reduces labor time required.  
         [0041]     Second, using the multi-fiber cables substantially reduces risk of damage to the individual fiber cables. The bundle of individual fiber cables is difficult to bend at a sharp angle, and the main cable hose further protects the individual cable fibers from damage.  
         [0042]     Third, the multi-fiber cables (after being laid) are easier to remove. The bundling of the individual fiber cables reduces the number of cables to remove and also reduces the chance of damage to the individual fiber cables. The main cable hose provides an additional protection for the fragile individual fiber cables.  
         [0043]     Fourth, the labor required to label the cables is reduced due to the built-in labels. In one embodiment, as depicted in  FIG. 2 , labels are built-in both on each end of the main cable hose and on each end of the individual fiber cables.  
         [0044]     Fifth, trouble shooting is simplified and facilitated using the multi-fiber cable as disclosed herein. The coloring of the individual fiber cables makes it easier to distinguish and identify each independent fiber. In addition, the built-in labeling may be used to further distinguish and identify each main cable and each independent fiber therein.  
         [0045]     In the above description, numerous specific details are given to provide a thorough understanding of embodiments of the invention. However, the above description of illustrated embodiments of the invention is not intended to be exhaustive or to limit the invention to the precise forms disclosed. One skilled in the relevant art will recognize that the invention can be practiced without one or more of the specific details, or with other methods, components, etc. In other instances, well-known structures or operations are not shown or described in detail to avoid obscuring aspects of the invention. While specific embodiments of, and examples for, the invention are described herein for illustrative purposes, various equivalent modifications are possible within the scope of the invention, as those skilled in the relevant art will recognize.  
         [0046]     These modifications can be made to the invention in light of the above detailed description. The terms used in the following claims should not be construed to limit the invention to the specific embodiments disclosed in the specification and the claims. Rather, the scope of the invention is to be determined by the following claims, which are to be construed in accordance with established doctrines of claim interpretation.