May 20, 2004

Permission is granted to distribute freely, provided that it is reproduced in its entirety and proper attribution is given.

An HTML version may be found at http://www.midasnetworks.com/5100AB.html

While this information is believed to be accurate at the time of publication, specifications will change, so these procedures may not work. Updates and suggestions should be sent to cb at midasnetworks dot com.

All trademarks are property of their owners (LESSnetworks, Efficient Networks, SBC, and Yahoo).

Midas Networks, Inc or Chris Boyd cannot be held responsible for use or misuse of the information contained in this document.

Installing PPPoE Hotspots with the Efficient/SBCYahoo 5100B DSL Modem

Part One: Differences between the 5100A and 5100B

The 5100A has four LEDs on the front: Power, Ethernet, DSL, and Activity.

The 5100A is a simple Ethernet to ATM/ADSL bridge. Ethernet frames go in, ATM cells with RFC1483 comes out, and vice versa. PPPoE works well, since the CPE does nothing more than encapsulation and SAR functions.

The 5100B five LEDs: Power, Ethernet, DSL, Internet and Activity. It also sports two rubber feet that allow it to stand on edge.

The 5100B is a much smarter device. This modem has the ability to run as a PPPoE client, PPPoE passthrough, or RFC1483 bridge. It includes a DHCP server. It is apparently able to autoconfigure to the passthrough mode when it sees PPPoE coming into the Ethernet port.

Part Two: Setting up the LESSnetworks Edge Server

Since the 5100B includes a DHCP Server, any DHCP requests coming from the eth0 interface are fulfilled. Alas, the DHCP information supplied is not useful. Your eth0 address will be 192.168.1.64, subnet mask will be 255.255.0.0, and the default route will be set to 192.168.0.1. No nameserver information is supplied, and the default domain name is set to domain_not_set.invalid.

Also, the PPPoE client supplied in the ES does not appear to be able to reliably reset the default route when it starts, so the ES is unable to route Internet traffic correctly.

The workaround is simple:

Edit /etc/sysconfig/network-scripts/ifcfg-eth0.

Change the line that reads "BOOTPROTO=dchp" to "BOOTPROTO=none". This brings eth0 up, but does not request DHCP info, so you don't learn the bogus info.

Run "adsl-setup" as you normally would.

Reboot.

When the ES is back up, do an "ifconfig eth0" and make sure that you don't have any IP address information.

Do "ifconfig ppp0" and make sure that you have valid IP information. For completeness, you can check "netstat -rn" and look for a default route to an IP address that is in the same /30 network as your eth0 IP, but it's not necessary.

Continue your ES configuration as normal, and enjoy!

Part Three: Warnings

DON'T HACK THE MODEM! If you're not on the phone with SBC tech support, don't try to reset the modem configurations. While technically possible, it's not recommended, since you can make the modem unusable. Stick to the ES, since if you screw it up, worst case is you reinstall the software.

-30-

May 20, 2004

http://www.midasnetworks.com

Permission is granted to distribute freely, provided that it is reproduced in its entirety and proper attribution is given.

An HTML version may be found at http://www.midasnetworks.com/5100AB.html