PPP y CHAP A3 ------------------- username B1 password cisco username B2 password cisco interface S0/0/0 encapsulation ppp ppp authentication chap B1 --------------------- username A3 password cisco username B2 password cisco username B3 password cisco interface S0/0/0 encapsulation ppp ppp authentication chap interface S0/1/0 encapsulation ppp ppp authentication chap interface S0/0/1 encapsulation ppp ppp authentication chap B2 ------------------------ username B1 password cisco username A3 password cisco interface S0/0 encapsulation ppp ppp authentication chap B3 -------------------------- username B1 password cisco interface S0/0 encapsulation ppp ppp authentication chap