Internet access w/ 56k csu/dsu

[maximumbob]

A friend claims access over a standard phone line (not leased) through a dotted quad on a university server. How is this possible?

 

[Xanathar]

though a dotted quad?

unless the phone line is straight throu, and has a csu/dsu on each end, or is set up for it, it has to be a dialup.