Bitcoin Forum

Hi, as per title it's either 3G or 56k - 3G would need reverse SSH and 56k might be too slow.

I don't know how much data transfer 8GH would do.

Thanks a mill.

I would go 3g. More bandwidth, and the possibility that it works more independent ;)

Data transfer is very limited. Latency on the 3g might suck but I'm not sure I'd pay for a phone line.

Why not get another broadband connection? Most places have $20-$30 plans which would be perfect as a failover.

Because it is not adviable to run desaster scenarios over the same cables. Also my problem with the 56k solution - someone hits the phone box of the street with a car, and both, modem and dsl are offline.

3g would not be.

In a building, all phone lines will run to the same station over similar cablings -> no desaster. 2 DSL only sae from DSL side issues.

Thanks. I'm going to go with 3G then.

Get one cable broadband and one DSL broadband.

It's Bitcoin mining. If it goes down when you have two broadband connections from two different companies for 3-4 hours, that's called letting your rigs cool down before you fire them up for another 6 weeks straight.

Currently I run 5 GPUs (~ 1700 MH/s) on single GPRS line, which is limited (because I easily overfill FUP) to 16 kBits/sec in both ways. Surprisingly, it is sufficient!

If you are mining in a pool with 8 GH/s, I think you'd be requesting about 2 new "getworks" per second, and sending in on average 2 new proofs-of-work per second. In addition is long polling. I guess this is several computers, so you'd have several long polling connections.

Let's say roughly that getting new work is about 800 bytes, sending 100 bytes to request it. Sending in proof-of-work means roughly sending 400 bytes and receiving roughly 100 bytes. Including both directions, about 2800 bytes, or 22400 bits per second. In addition there would be a spike at every block change, from the long polling connections. Sounds totally doable.

56K dialup is sufficient, though I'd expect a slight increase in stales from the increased latency.

Go 3g, and if you get a huawei modem don't forget to do the trick to be on HDSPA (low latency) all the time and not fall to WCDMA (high latency).

+1

56K would not be too slow, as its faster than no connection (and sufficient) in the event of a failure.

Failure of both connections is a non-issue. If we are talking about a failure of both phone lines and DSL/cables lines at the same time, sounds like a serious event such as a storm. In which case the power will be out anyway. So its moot.

I love ignorance.

No, we do not.

We talk of someone pulling down the phone cable. Can happen outside of a storm just  by accident. if you are in the US, those lines are likely over land - have a car crash into it and they both go down. Have some builder cut the cable and they both go down. have a fire in the phone company and they both go down.

Been there, seen that.

There is no reason not to run the backup over something that runs over separate lines. 3g for example.

I give you one example of my "CoinCore" data center we are signing contracts for monday ;) In this case it is an old factory - I get DSL there installed as mains, and on top I have the nice power coming in by high  voltage lines (power station over the street in the complex - not even 30 meters, taking it down to our 408 volt 3 phease, i.e. 230 volt).

There are many scenarios I can envision where DSL or power can fail separately. There is nothing I can do for pwoer (USV are just not worth it), but I can:

* Run a local pool proxy, so there is not a ton of open connections for long poll out of the building.
* Run my  backup over 3g / UMTS or even LTE when it comes (IF it comes).

In cae some stupid renovation somewhere (not unlikely at the moment) cuts the phone line.... nothing happens ;) The price is neglegible (actually it is - I get it into a package with the DSL line).

One of the ethernet ports on my 4-gpu rigs died a few months back;
As an emergency solution over the weekend (no spare ethernet cables) I plugged in a Nokia N8 phone via USB and used it as a 3G modem.

Worked just fine for 3 days of mining. The bandwidth is about 4kb/s.

i have about 1 kilobyte/s peaks per 1gh/s if i read my router menu correctly
so 56k probably would slow down your 8gh/s

maybe dual isdn?