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Comment Protect you against SQL injection? Really? (Score 3, Insightful) 90

I would love to hear the explanation of how a general purpose language would protect you against attacks like that, clearly called out in the article.

You're doing the snowflake thing, blaming everyone else for the coders' incompetence and unsuitability for the job. Some dweeb wrote a tutorial and because it's not ready to be cut and pasted into production code, that's the tutorial writer's fault.

NB: Not everyone can code.

Comment Re:I blame Trump. (Score 5, Insightful) 1149

Well, that's one way of looking at it. Another way is that black people do a lot more murder on a per capita basis. As it turns out, the chances of getting killed by a white guy are less for a black person than the reverse. Which is indicative of the overall murder rate in the black community being several times (something like 5+ times) what it is amongst whites.

Some source data

Anyway paying undue attention to a single person amongst the 6k or so that are going to die this year is politically motivated, as usual.

Comment Re:I blame Trump. (Score 2, Insightful) 1149

I agree with you. People say a lot of stupid things when they are drunk. But let's not let any opportunity to blame Trump go to waste, right?

And Leftists wonder why they are getting tuned out.

500 white people are killed by blacks every year and 200 blacks are killed by whites every year. One group is 70% of the country, the other is 13% of the country. I notice the same people whining about this event aren't paying attention to those statistics. A couple people assuredly died in interracial murders since that story broke.

But this one drunken fight in Kansas - we have no idea what was actually said and what provoked this - is somehow more significant.

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

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