Through the analysis of the capabilities of new communication network taking Internet as representative

the STL system model of new communication network was put forward

which has three dimensions including space domain

time domain and language domain

and was comprised of three elements including transmission capability

memorization capability and computation capability

on the basic of the STL mode

the principle of transformation between the com-munication capabilities was proved. From the interpretation of the current Internet application services

it can be said that the STL mode has certain use for the development of communication theory and network technology.