These devices can be fusion spliced together to maintain a low gap loss after generating a quality cleave in them using the scribe-and-tension method. These devices are produced from multi-story draw towers. Erbium-doped amplifiers are used in conjunction with these devices to prevent degradation and allow them to leverage wavelength-division multiplexing. The acceptance angle of these devices corresponds to their numerical aperture. Dispersion limits the maximum length of the multi-mode types of these (10[1])waveguides, which have a higher ratio of core to cladding diameter than their (10[1])single-mode type. For 10 points, total internal reflection confines light inside what long, (10[1])thin communication (10[1]-5[1])devices used for high-speed Internet? ■END■ (0[1])