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Network Configuration—PPPAs we have configured PPP daemon, it reads the usernames and passwords from the/etc/ppp/ppp.secret file. The format of this file is pretty straightforward and thepasswords are kept in a cleartext format. A typical ppp.secret file looks like this:johnbabakMyPa$$word3ecRe+The first parameter in each line specifies the username, and right after that,separated with a space or tab, is the password.Setting up PPPoE ClientThere may be certain circumstances when you have to run PPP over a packetswitchednetwork (for example Ethernet), instead of a circuit-switched network (forexample PSTN), as in the case of broadband access services such asADSL.Basically, service providers need to authenticate or authorize users, and alsocalculate their usage statistics for billing or other uses. PPPoE is very suitable forthis scenario, as there is an Ethernet network extended from your workstation to theservice provider edge, using broadband access technologies. In a PPPoE scenario,you are like a dial-up user from a service provider's point of view except the fact thatyou are using a broadband connection instead of serial connection.The provider will terminate PPP connection on a Broadband Remote Access Server(BRAS) platform to perform the per-user Authentication, Authorization andAccounting (AAA) as well as routing traffic towards external networks.From a user's point of view, PPPoE seems like a normal PPP connection, except whenyou do not have to actually dial a destination number. The PPPoE client discoversPPPoE server by broadcasting PPPoE Active Discovery Initiation (PADI) messageover available (or specified) Ethernet links.Setting up a PPPoE client session in FreeBSD 7 is almost as simple as initiating adial-up connection. A sample /etc/ppp/ppp.conf file for PPPoE looks like thefollowing code:default:set log Phase tun commandenable dnsyourprovider:set device PPPoE:fxp0set authname YOURUSERNAMEset authkey YOURPASSWORDset dialset loginadd default HISADDR[ 152 ]