In telecommunication, a tactical data information link—A (TADIL—A) is a netted link in which one unit acts as a net control station and interrogates each unit by roll call. Once interrogated, that unit transmits its data to the net. This means that each unit receives all the information transmitted. This is a direct transfer of data and no relaying is involved.
References
Tactical data information link–A Wikipedia(Text) CC BY-SA