ADSL usb modems

[Rick Stevens]

Graeme Nichols wrote:
> On Thu, 2004-05-06 at 02:48, Rick Stevens wrote:
> 
>>Graeme Nichols wrote:
>>
>>>On Sat, 2004-05-01 at 02:59, Rick Stevens wrote:
>>>
>>>
>>>>Graeme Nichols wrote:
>>>>
>>>>
>>>>>On Tue, 2004-04-27 at 02:32, Rick Stevens wrote:
>>>>>
>>>>><snip>
>>>>>
>>>>>>There are some ADSL modems that work fine with Linux and some that
>>>>>>don't, just as there are some winmodems that work and others that won't. 
>>>>>>Keep in mind that this is not just a Red Hat issue--it's a general Linux
>>>>>>issue with manufacturers not helping an open source solution.
>>>>>
>>>>>
>>>>>Do you have the names of those usb ADSL modems that DO work with Linux,
>>>>>or point me in the right direction to find out?
>>>>>
>>>>>I am a bit disappointed to learn that there are not only 'gutless'
>>>>>dial-up modems out there but 'gutless' ADSL modems as well. The way
>>>>>things are going, the next time one buys a new car the engine and drive
>>>>>train will need to be supplied by the 'driver' :-)
>>>>
>>>>http://www.linux-usb.org/ is the list of USB stuff.  I don't know if
>>>>they have USB cable or DSL modems, but you can check.
>>>
>>>
>>>Hello Rick, they didn't have all that much. I finished up buying a
>>>Billion BIPAC-5100 ADSL Modem/Router and a Dolphin PCI 6003 Ethernet
>>>10/100Mbps Ultra Power Series nic. As well as the Windows logo it has
>>>Tux as well on the box. Amongst all the bulleted features it claims is
>>>the following: 'Supports the widest range of drivers for common network
>>>systems such as Novell, IBM, Windows, SCO Unix and Linux.' So, it should
>>>be OK.
>>
>>That's fine.  In my experience the most compatible (and stable) set up
>>is a stand-alone modem (cable, ADSL, whatever) with an ethernet port,
>>a separate router/firewall (I use D-Link units, but Linksys and others
>>are good except for Belkin), and either WiFi or hard-wired ethernet.
>>
>>NEVER use Belkin firewalls or routers.  After that last debacle where
>>the firmware would periodically "steal" one of your connections and
>>route you to an advertising site, I wouldn't trust them as far as I
>>could throw their corporate office building.  B*stards!
>>
>>
>>>The router was the Editor's Choice in an APC magazine article on such
>>>devices last February so I fully expect it to function OK.
>>
>>I'm not familiar with that make (Billion), but if APC says it's good,
>>then I'd feel fairly comfortable.  I don't use DSL myself (I use cable
>>modem--I'm too far from the central office for DSL to be worth it), so
>>any comments I make would be anecdotal at best.
>>
>>
>>>The freebie ADSL usb moden supplied by the ISP is a D-Link DSL 200 and
>>>according to the D-Link web site only supports Windows (only Windows
>>>drivers available) so it is akin to a 'winmodem'
>>
>>Yup.  I have several friends at D-Link and I'm trying to get them to
>>start supporting things on open source more.  The problem is that the
>>makers of the chipsets they use (Texas Instruments being the worst
>>offender) supply the drivers to D-Link in binary form so not even they
>>can play with them without reverse-engineering them.
>>
>>
>>>The article I mentioned above strongly suggested to avoid ADSL usb
>>>modems as they "suck CPU power; they don't always co-exist peacefully
>>>with other usb devices; they need special drivers for each operating
>>>system; and they are incompatible with some motherboard chipsets and
>>>BIOS firmware. Ethernet has none of these disadvantages."
>>
>>This isn't always true.  It depends on how the thing is made.  If it
>>depends totally on the USB bus to power it (like a FLASH stick), then
>>yes the power concerns are big.  Due to the processing they do, they can
>>hang the USB bus at times, too.  As far as I'm concerned, I only use USB
>>for the things it was really intended for...connecting storage devices
>>and HID.  I don't use it for networking.
>>
>>
>>>One last question, Have you, or any one else, had any feedback on
>>>Dolphin nics? The vendor, Dick Smith Electronics, claim they have never
>>>had any complaints.
>>
>>It rather depends on the chipset used on the card.  If it's a "name
>>brand" (3Com, Intel, DEC, etc.) you should be OK.
> 
> 
> Rick, I installed it and booted Linux. It was found during boot-up and
> Linux installed the drivers OK. It is a RealTek RTL-8139, SMC EZ Ca.

Terrific!  Yeah, the RealTeks are being used a lot on mobos now.
They're pretty good.  Not the fastest thing in the world, but
reasonable.

> Linux talked to the ADSL modem/router straight away. Now... as soon as
> Telstra (our local telco here in Aust.) activates the line for ADSL I
> can configure the modem/router and be away, hopefully :-)

Great!  And away we go!  Make REAL sure you set up a VERY restrictive
firewall, Graeme.  Don't allow anything IN except the absolute minimum
of what you need.  In my case, it's DNS (TCP/UDP port 53), SSH (TCP
port 22) and NTP (TCP/UDP port 123).

Turn off any daemons you don't need (e.g. don't portmap unless you're
running NFS or need FAM) and restrict those you do need to your local
network (probably 192.168.0.0/24 or whatever the local side of the
router is).  Make sure no other daemons or xinetd are listening on some
weird ports (run nmap/nmapfe on your system).  Try to run something like
tripwire on your system, too, so you can see changes to your
filesystems.

> When I booted up Win98 SE to set it up there I had a lot more "trouble',
> you know how it is with Windows... "Insert the WIN 98 CD", re-boot,
> etc., etc. One side problem though, it has been so long since I booted
> into Windows I keep using Linux commands through force of habit which
> Windows is too dumb to understand. :-)

Heheheheh!  That's an issue.  My major problem is switching keyboards.
I have to use about six different ones at various times and locating the
ESC, ALT, SHIFT and BACKSPACE keys can be tough (especially on those
bloody Sun keyboards!).
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- Rick Stevens, Senior Systems Engineer     rstevens at vitalstream.com -
- VitalStream, Inc.                       http://www.vitalstream.com -
-                                                                    -
-  Silence!  Or I shall replace you with a very small shell script!  -
-                                                - The Wizard of OS  -
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