Using contest logger over internet with remote Flex-6700 and NO remote PC attached

Kari Gustafsson SM0HRP

You are right Chris. The only difference with the analog legacy remote set-up is that now we are dealing with more or less a full digital radio chain. The intrinsic robustness of the digital chain each with their operating systems make the overall system MTBF something worth considering. I remember when  operating remote over 400 kbit/s over dsl (4 years ago) with legacy radios that was a fairly simple simple manouver even 24/7.  Except RFI not much could go wrong than interfacing different suppliers RS-232 equipment (e g amplifiers). Working contests was quite a feasible task. 
Now with "all digital" I feel the redundancy issue becoming perhaps the most important task. How do you systemize now? Splitting controll channels  from traffic channels, multiple WAN sources over indepenedent WAN service providers e t c. 
It would be very very interesting to hear more about this from the leading remote contest stations like yours. One such in EU said to me: "Well I still keep the legacy set-up when the big contests set in". I myself believe that I need to do it at least for a year or so when running the major contests.   How starts this thread? 

ctate243

Many routers support mutiple wan links now.  I have not tried them, but I imagine it uses some type of transfer system that must me more rudimentary than border gateway protocol thus probably doesn't re-advertise a single IP so cutover would not be clean.. I am curious how those dual wan routers work.

Ria

I have multi WAN but only as a failover (to 4G LTE). I would do bonding but it won't fix my main pain point which is upload. Hopefully my friends in the engineering dept at the cable co haven't forgotten me yet...

ctate243

Hi Ria I suspected you may know, how long does it take for a failover?  what is the impact on existing connections? for instance is it a momentary complete connection loss.. etc.?

Ria

Since this is an emergency failover, I set it to trigger based on "member down" which means that there must be 100% packet loss. As soon as the firewall detects 100% packet loss, it fails over. This could take a few seconds. If I wanted, I could set a lower threshold, eg. more than 20% packet loss, in which case the failover would be more seamless. 

Each connection is also in a tier. The 4G connection is a lower tier than the cable modem. You can set the links to load balance, failover or a combination of the two.  This can make the switchover virtually instantaneous, however established connections would lose state if they are on different ISPs for consumer internet connections. However, in our data center setup we have our own class C and we can and have seamlessly failed over, automatically and manually. 

ctate243

This technology seems like it would be more useful to shore up a control side rather than a remote side...

Ria

If you have your own IPs and the ability to reroute them it would work for the remote side. Otherwise, no.