Labels:text | screenshot | parallel | rectangle | line | diagram OCR: A CHALLENGE-RESPONSE PROCEDURE Authentication device A Authentication device B Remote access device 1 Sends PIN Laptop 2 Uses PIN and device A's unique key to generate challenge Uses challenge, PIN, and own key to generate response Device B'also generates response using challenge, PIN; and device A's unique key If the two responses match, device B grants the user access 5 LAN Figure 3. The safety in a challenge-response system lies in its ability to avoid sending a password or a key, either encrypted or decrypted, over the public telephone line and to authenticate users for single, one-time-only events.
