A Library on a Card: Copying Time and Energy for an Offline School Library

An offline digital library is only useful if it can be copied at school scale. This paper computes copying time for a stated 32 gigabyte library onto one card and onto a class set of thirty, sequentially and through a four-port hub, and prices the cards. The bound is logistical, not electronic: distribution day, not download speed, is what a school must plan, and the paper sizes it. Computed results: copy_one_card_usb_min = 26.7, copy_one_card_sd_min = 35.6, class_set_sequential_h = 17.8, class_set_4port_h = 4.7, card_cost_each_usd = 6.0, class_set_cards_usd = 180.0. Every number in this paper is produced by the accompanying script `compute.py`. SIMULATED, NOT MEASURED.