[lug] Cisco 678 and NAT

[Dan Ferris]

> Dan Ferris wrote:
>> I have experience with 2 Cisco 678s.  I think they are the best DSL
>> modem out there personally.
>>
>> The best way to use one is to get a seperate router and run them in
>> bridging mode.  I do that with a Soekris box running m0n0wall and it
>> NEVER crashes.
>>
>> Just my $.02
>>
>> Dan
>
> Both bridging and PPPoA has benefits and problems.
>
> While it's true that bridged mode is the most convenient for those of us
> that like messing with our own firewalls, etc... because we're just
> seeing all the way to our upstream router, and it means we don't have to
> deal with routing between the firewall and the modem...
>
> Bridged mode rarely recovers correctly from a line failure without
> power-cycling the 678.
>
> Also depending on your ISP, they can whack up their ARP tables during
> router/switch software upgrades and you'll find that even though you
> have physical layer and what appears to be logical layer connectivity...
> nothing works until you do the magical power-cycle of the 678 to force
> some ARP'ing for stuff to straighten out their end.
>
> I used to have a bridged-mode SDSL circuit long ago, and these were both
> "common" problems... probably twice or three times a year.
>
> PPPoA (or PPPoE - whatever) will reconnect more cleanly and with more
> chance of recovery if the circuit is bouncing or power to the DSLAM is
> bouncing.  (Summertime... t-storms, etc.)
>
> If you're running static IP's and have more than one range, bridged
> setups can become a bit confused with that setup, also.
>
> I've had two /28's routed to my 678 for a number of years now over PPPoA
> and I can't remember *ever* having to reset my 678 to clear a down
> connection, ever.  PPPoA has simply taken care of it.  I've reset the
> 678 only to move it or change power connections.
>
> Some of that might have something to do with connecting to a VERY good
> ISP with a clue, also... this is NOT on Qwest ISP service.  Qwest
> transport to Front Range Internet (FRII).
>
> The downside?  Not huge... I have to add a default route from the
> firewall to the 678.  I'd have to point it upstream to the ISP's default
> router for the bridged network anyway, so no additional work needed
> there.  I had to put a username and password into the 678 also, of
> course... that's about the only difference from my end of the connection.
>
> Nate
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>
>

I point out bridging because I've used it for just about a year.  With the
old POS Broadextant box I used to have it sucked.  But the 678 NEVER
crashes.  It's great. :)  Power cycling the 678 isn't that big of a deal
either for me it comes up in about 30 seconds.

My dream is for there to be 1 megabit upload DSL that is affordable
heheheheheh. :)

73
Dan