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Comment and for pete's sake, MTU!!! (Score 2) 325

A lot of times, bad MTU settings are the problem with a sat link. The problem is simply stated: GRE tunnels are common on such links, and a GRE tunnel will encapsulate each packet and add a 16 byte header. Since the modems usually only permit a 1500 byte MTU, this means the maximum packet size you can get through the GRE tunnel will be 1484 bytes long, inclusive of header. If someone sends out a packet that is maximum size for a 1500 byte MTU, and sets the DF (Don't Fragment) bit, when the packet hits this GRE tunnel it will be dropped. This happens frequently with bad SSL implementations.

This is only one version of MTU problems with sat links. There are others.

Comment Tips for Dan Luu (Score 2) 325

The problem with a satellite connection is not precisely related to latency but rather to jitter, the large differences in latency from one packet to the next. This happens as a result of rain fade, or a poorly engineered link to your transponder on the bird, or a variety of other more infrequent issues.

You can (and should) up your TCP timeout values from the default 3 seconds on a satellite connection, and adjust the http keep-alive timeout, etc, but a lot of times this just means you wait longer to be told when the connection fails.

The solution is a combination of caching, compression, and a performance enhancing proxy or PEP. The PEP does TCP spoofing, basically faking the acknowledgements to speed up the transmission of packets. Compression is similar to the MNP5/v.42bis stuff from modem days applied to a satellite connection. Caching is basically Squid. A lot of PEPs combine all three functions into one - Riverbed is a really good example, though i've worked with pretty much every vendor and they all do the same stuff, with differences in ease of use and efficency.

Implement the timeout fixes, implement a good PEP with all three of the ingredients noted, and make sure the connection is dialed in well with a good shot (line of sight) without physical impediments like trees, buildings, and most importantly microwave interference, and you should have a fairly reliable internet connection. You will still take hits, but you can look at the front of the satellite modem and see that is happening if it's an iDirect or something similar.

Bottom line though is that unless you are taking hits, you should be able to set up downloads of a lot of images and never see a timeout.

- someone who has spent a lot of time doing this (and living off sat connections) in awful places in the world

Comment Since no one apparently said it (Score 1) 588

Twitter doesn't do government services and they'll be out of business shortly. Also, their leader is a left wing ideologue.

The rest of the companies would gladly take on the work. This surprises you how?

Did you somehow think that your ideology was going to keep on preventing people from working with Trump without political power? Think again.

Comment They won't. (Score 1) 333

Period. It's a waste of time. Any government that tries to force standard of living reduction will be voted out of office. This is essentially what happened with Obama, and he tried to do it in a stealthy way. Imagine someone openly taking an axe to public prosperity in the interest of climate change? They'd shove knives up his ass like Quaddafi.

You have to create a totalitarian state with the full apparatus of secret police, surveillance, detention camps and summary executions to even start to go there, and the focus on climate change would impair your ability to maintain that social control. Beside which, the inherent corruption in such a state would ultimately subvert your efforts to reduce your carbon footprint.

Also, i'd rather have the climate change than the secret police, thanks.

Comment I've never seen so much effort futilely wasted (Score 1, Insightful) 333

The climate change police are getting more and more shrill over time. This decreases rather than increases their power to convince. But it was all futile anyway because you are asking people to reduce their standard of living by choice to accomplish a community goal. Even people who see the danger are loath to do that...thinking Al Gore and his planes and houses. It's the Whole Earth Catalog thing all over. "living guilt-free with our appropriate technology like Indians in the woods...free at last!". Only a tiny percentage of people will ever share in that goal meaningfully.

Nothing is going to change politically even when the oceans start encroaching cities, because the argument then will be that it is too late to fix the problem at that point. So, why bother with the stupid political activity, when we all know it's a nonstarter? Aren't there more constructive uses for their time? Instead of futile political activity, how about carbon sequestration-related work? Fund startups to do that... Plant trees. Do *something* to combat the problem you see rather than all of this wasted political activity...dare I say hot air? Solve the problem and stop trying to force others to change to 'solve' it.

But they won't, because it's not really about climate change. It's about social control and mandating lifestyles. People who apparently really don't like personal success very much because they choose goals that are unachievable.

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