Abstract: Internet-protocol based, virtual private networks are configured by first identifying the basic components of such networks and then efficiently assigning MPLS-based RD and RTs to each component or efficiently generating VR-based access lists for each component.

Abstract: Internet-protocol based, virtual private networks are configured by first identifying the basic components of such networks and then efficiently assigning MPLS-based RD and RTs to each component or efficiently generating VR-based access lists for each component.

Abstract: Disclosed are aligned plug optical fiber connectors. A preferred embodiment of the inventive connector comprises two cylindrical glass plugs, a glass alignment block of L-shaped cross-section, and a bifurcated metal spring clip that separately urges each plug against the two reference surfaces formed by the arms of the alignment block. The presence of a recessed portion of one of the reference surfaces is optional and can facilitate rotational tuning of the fiber connector.

Abstract: An animal-resistant optical fiber cable (20) includes a core (22) which comprises a transmission medium and a sheath system. The sheath system includes an outer jacket (65) and a dielectric armor (40) in the form of a shell. The shell comprises a plurality of longitudinally extending preformed segments (42--42) each being a composite comprising a substrate portion (50) and a layer (52) of a coating material which has a relatively high hardness disposed on an outer surface of the substrate portion. Each of the segments covers less than half of the periphery of the core and, in a preferred embodiment, eight segments are used. Further, the shell segments are stranded helically about the core with at least portions of longitudinal edge surfaces of adjacent segments being in engagement with each other. The shell segments not only provide rodent protection for the cable, but also they provide suitable tensile and compressive strength as well as suitable flexibility and cable bending performance.

Abstract: An animal-resistant optical fiber cable (20) includes a core (22) which comprises a transmission medium and a sheath system. The sheath system includes an outer jacket (65) and a dielectric armor (40) in the form of a shell. The shell comprises a plurality of longitudinally extending preformed segments (42--42) each having a cross section transverse to a longitudinal axis of the cable each of which covers less than half of the periphery of the core. Further, the shell segments are stranded helically about the core with at least portions of longitudinal edge surfaces of adjacent segments being in engagement with each other. The shell segments not only provide rodent protecting for the cable, but also they provide suitable tensile and compressive strength. Further, because the cable in the preferred embodiment has an all-dielectric sheath system, it is inherently lightning, corrosion and EMP resistant.

Abstract: A communications cable comprising a core of transmission media such as optical fibers, for example, disposed in a core tube and a sheath system (32) includes provisions for preventing the movement of water within the cable core. Water blocking provisions (26) are disposed in the core tube and may comprise a tape or a yarn, for example, or both. The tape may comprise substrate tapes between which is disposed a superabsorbent material in powder form which upon contact with water swells and inhibits the further movement of the water. In another embodiment, a water swellable yarn may extend longitudinally linearly with the optical fibers in the core.

Abstract: Disclosed are aligned plug optical fiber connectors that can accommodate larger differences in plug diameter and/or a wider range of plug diameters than is possible in prior art connectors, resulting inter alia in increased economy. The first of these advantages is attained through the use of bilaterally decoupled plug alignment means, i.e., means in which radial deformation of one half of the alignment means does not result in analogous deformation of the other half. A simple example of bilaterally decoupled alignment means is an alignment sleeve with a centrally located lateral slit. The second of the above advantages is attained through use of limited contact bilaterally decoupled alignment means, i.e., bilaterally decoupled alignment means shaped such that only a limited portion of the plug surface is in contact with the alignment means. A simple example of such alignment means is a transversely split alignment sleeve whose bore has roughly ellipsoidal cross-section.

Abstract: An optical fiber connector of the continuous groove type comprising a substrate with a multiplicity of fiber-receiving grooves thereon, and a cover member comprising compliant fiber-contacting material having a modulus of elasticity less than about 10.sup.6 psi (less than about 6.9 GPa), preferably less than 10.sup.5 psi. Connectors according to the invention can have low loss, and low added loss during thermal cycling. In a particular preferred embodiment, the substrate is a molded plastic part, and the compliant material is an adhesive-backed polyester film.

Abstract: A low loss optical fiber splice comprises first and second assemblies (52--52) each of which terminates an optical fiber. Each assembly includes a plug (30) that has a passageway (32) extending therethrough with a fiber positioned therein and having an end face (34) extending at least to an end face (36) of the plug. Each plug is received in a housing (59) which has a flange (66) at one end thereof and a bore (64) to allow the fiber to extend therethrough. A collar (68) and a spring (69) are disposed about the housing with the spring engaging the housing and the collar. After a fiber is secured within each plug, the fiber cores (24--24) are aligned with a curable optically matching adhesive material being injected between the end faces thereof. Then the adhesive material is cured to lock the fibers in an aligned position and to secure the plugs together. Afterwards, the collars are moved toward the housing bodies to compress the springs and the flanges are positioned in nests (71--71) of a support frame (54).

Abstract: In order to recoat bared end portions (32--32) of optical fibers (34--34) which have been spliced together, the spliced portions of the fibers and portions adjacent thereto are positioned in a groove (51) of a base plate (43) of a mold and enclosed with a cover (60). The cover is slidably moveable relative to the groove to allow an injection nozzle (81) which extends through the cover to become aligned with the fiber. Coating material (92) is introduced through the nozzle into engagement with the spliced end portions after which the cover is moved relative to the base plate to shear across the coating material along the interface between the cover and the base plate. Movement is discontinued when a channel (86) in the cover becomes aligned with the recoated splice.

Abstract: An improved optical cable (10) having increased bending flexibilitiy along with increased tensile strength comprises means for controlling coupling between a cable jacket (28) and its reinforcing strength members (26). In one embodiment, a reinforcement bedding layer (23) is applied between a plastic-extruded inner jacket (22) and the outer cable jacket (28). Before extrusion of the outer jacket (28), the reinforcing strength members (26) are helically applied onto the bedding layer with predetermined strength member surfaces (27) making intimate surface contact with the bedding layer. Because the bedding layer is impervious to the plastic extrudant used to construct the outer jacket and is capable of rendering the predetermined strength member surfaces sufficiently inaccessible to the plastic extrudant, encapsulation of strength member lengths (25) containing the predetermined strength member surfaces (27) by the plastic extrudant is prevented.