336Wide Area Network TerminationPPPoE/PPPoA (Point-to-Point Protocol over Ethernet/ATM)The PPPoE specification, incorporating the PPP and Ethernet standards, allows your com-puter(s) to connect to your Service Provider’s network through your Ethernet WAN connec-tion. The Netopia-series Gateway supports PPPoE, eliminating the need to install PPPoEclient software on any LAN computers.Service Providers may require the use of PPP authentication protocols such as ChallengeHandshake Authentication Protocol (CHAP) or Password Authentication Protocol (PAP).CHAP and PAP use a username and password pair to authenticate users with a PPP server.A CHAP authentication process works as follows:1. The password is used to scramble a challenge string.2. The password is a shared secret, known by both peers.3. The unit sends the scrambled challenge back to the peer.PAP, a less robust method of authentication, sends a username and password to a PPPserver to be authenticated. PAP’s username and password pair are not encrypted, and aretherefore sent “unscrambled”.Instant-On PPPYou can configure your Gateway for one of two types of Internet connections:• Always On• Instant OnThese selections provide either an uninterrupted Internet connection or an as-needed con-nection.While an Always On connection is convenient, it does leave your network permanently con-nected to the Internet, and therefore potentially vulnerable to attacks.Netopia's Instant On technology furnishes almost all the benefits of an Always-On connec-tion while providing two additional security benefits:• Your network cannot be attacked when it is not connected.
