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Comment Re:Win/Win (Score 1) 73

I support competent workers with a strong work ethic...which is precisely why I don't support unions. Having joined unions in two separate industries ( well, conscripted is more the right term as I didn't have a choice of the matter ), I saw just what "supporting each other" amounted to. The least competent, least ethical, workers were protected from any disciplinary action...ever, and as a result gained seniority. New folks would start and be full of energy and ideas, ready to work hard and make a difference, only to be stifled and discouraged by the more senior workers.

The best would leave, the rest would get beaten down and join the system.

Then, when there would be layoffs, the best staff was shown the door first while the wastes with seniority would be safe.

So no. No, I don't support unions.

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 Re:Language selection (Score 1) 312

One of the other reasons I recommended C# ( over java ) was that the development environment is more streamlined; it's easier to produce functional, non-trivial, code ( for beginners anyway ).

I get where the C recommendation came from, but there's more to the fundamentals than loops and decisions. Object orientation is fundamental too.

Comment Language selection (Score 1) 312

I don't know that I'd start with C. If you are a Windows user, I'd suggest C#. A) It starts you off right with object orientation, and B) It's probably one of the fastest paths to useful code, with a gui ( if that's important to you ).

There are thousands of tutorials out there to get you going too, so there's that. If you are completely green to programming, this won't be easy, but it'll be better that C.

Comment Re:Oh for goodness sake (Score 1) 303

You can get "dumb" LCD TVs, I got one about 2 years ago, 50 odd inch. Since the hi-fi is underneath it, it's straightforward to route the audio through something with better speakers. It turns on far quicker than my old (and much beloved at the time) Trinitron display, no tube to warm up - sub 1 second startup. The picture quality is so much better than the Trinitron it's like night and day.

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