Sneakernet may be used when computer networks are prohibitively expensive for the owner to maintain, in high-security environments where manual inspection (for re-classification of information) is necessary, where information needs to be shared between networks with different levels of security clearance, when data transfer is impractical due to bandwidth limitations, when a particular system is simply incompatible with the local network, unable to be connected, or when two systems are not on the same network at the same time.