Waveguiding properties of the higher-order modes in solid-core photonic-crystal fibers are studied numerically. The dispersion diagram is calculated for glass fibers with refractive indices of 1.611 with a hole-to-period ratio of 0.5 and 0.8. It is shown that, below the cutoff of the higher-order core modes, frequency regions exist within which these modes may propagate due to bandgaps in the cladding. In other words, the guiding effect in the solid-core fibers may result both from total internal reflection and from resonant reflection by the periodic cladding.
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