Nonsubstitutable infrastructure is something that so strongly holds users, a competitor can't get them to replace it. It has following characteristics: High switching costs for replacement.

Nonsubstitutable infrastructure technologies, by definition, support high switching costs (rendering any lower acquisition cost moot). Their total or near-total permeation throughout a business ...

The Academy of Management Journal, Vol. 47, No. 6 (Dec., 2004), pp. 843-859 (17 pages) This paper explores the effects of partner substitutability and alliance network structure on organizational ...