The analysis method recently proposed by Seaton and coworkers was applied to determine the pore network connectivity of hyperporous solids-silica aerogels. The mean coordination number of the pore network of silica aerogels was found to lie between three and eight, depending on the pore volume of mesopores and micropores, and independent of bulk density of the aerogels. Calculations of the effective diffusivities of aerogel samples clearly show that silica aerogels exhibit remarkable mass transport properties, significantly higher than conventional silica or alumina porous supports.