User`s guide

Accessing Connected Devices and Managing Power 119

Obtaining and Using One Time Passwords for Dial-ins

Some sites choose to print out hard copy lists of OPIE passwords for their

users and deliver them by methods such as FAX or FedEx.

• Make sure users are equipped with an OTP generator that is not on the

network to generate their own OTP passwords when challenged at login

time.

The OTP generator may be a copy of the opiekeys program installed on the

user’s workstation, or it may be an OTP token card.

T To Generate an OTP Password When

Challenged at Dial-in

Following is an example procedure for a user who has /etc/opiekeys

installed on the user’s workstation:

1. Dial into the OnSite through a PCMCIA modem or phone card that has

been configured to use OTP authentication.

The OnSite challenges with a sequence number (also called a counter) and

a seed (or key) associated with the username and asks for a response.

The seed includes the first two letters of the hostname and a pseudo

random number.

The challenge is otp-md5 499 on93564. The sequence number /

counter is 499 and the seed is on93564.

2. Obtain an OTP password by performing the following steps.

a. Copy the entire challenge into a window on a computer where the

opiekey program is installed.

The otp-md5 portion of the challenge is a symbolic link to the

opiekey program and tells the opiekey program to use the MD5

algorithm. opiepasswd then prompts the user for the user’s secret

pass phrase.

b. Enter your secret pass phrase when prompted.

otp-md5 499 on93564

Response: