Introduction to Point to Point Authentication : PAP and CHAP protocols
PAP and CHAP is one of the basic and most important topic for CCNA candidates or the freshers who are going to work on the Point to point networks.
Before we are starting with the PAP and CHAP protocols, I would like to tell you that PAP and CHAP is the authentication procedure in Point to point network. So if you are using Point to point networks in your architecture you should opt for PAP or CHAP protocols as per the design required.
Below is the example showing the pictorial representation where we are defining the acceptance and the refusal of the connection in both the cases.
PAP- Password Authentication Protocol
So PAP is a password-based authentication protocol used by Point to Point Protocol (PPP) to validate users. PAP generally consider as a very basic two-way process. There is no encryption. The username and password are sent in plain text. If it is accepted, the connection is allowed.

It follows reports that Broadcom is planning an unsolicited bid for chipmaker Qualcomm.
This follows yesterday's news that Broadcom is relocating its headquarters to the U.S.
NetApp teamed up with Cisco on converged infrastructure seven years ago.
Expect more consolidation of SD-WAN and networking vendors to come.
Black Duck’s security technology automates the detection of vulnerabilities in open source software.
CenturyLink closes on Level 3 for $34B; Microsoft Azure to triple its capacity in China; Telefonica Chile virtualizes its core network with Ericsson.
The company’s revenues grew 50.8% year-over-year.