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Comment Re:O Hai. Has this been posted? (Score 1) 190

That seems a very sophisticated, enlightened, multi-layered approach. It can be very difficult to implement so broadly if your mail services are in the hands of another corporate group. MS Exchange managers, for example, can become quite concerned and upset if you want to implement greylisting and SPF blacklists before it even reaches their mail servers, but that's where it's most effective.

Merging the SpamAssassin checks into larger but more efficient regexp statements is a useful technique that I'd encourage you to publish, especially if you publish the tools to build those new rules and move aside the old ones.

Comment Re:O Hai. Has this been posted? (Score 1) 190

Thank you for posting that checklist, that's a vital document for any spam planning.

SpamAssassin, executed through procmail on the mail client's email, is indeed resource intensive and does not scale well for an organization. Other people have mentioned other upstream filtering techniques, such as grey listing and DNS blacklists, but those are limited because of the large numbers of zombied Windows clients around the world, which have their resources rented as botnets to send spam from legitimate environments around the world, partly to evade these filters.

My experience is that spam requires management, not silver bullets. Layers of defense such as supporting SPF, which filters very early and cheaply based on DNS records, helps eliminate most forged and and other large domain phishing. More powerful, more expensive filters such as SpamAssassin can be applied on the vastly reduced volume of email that gets past the earlier filters. Unfortunately, if you're processing with a local "procmail" by pulling the email from the mail server to your local machine, it's already too late to activate DNS blacklists or SPF, so the increasing burden on SpamAssassin is predictable.

I'm afraid I don't have a great solution for the original poster except tp push the filtering upstream, to the mail server itself, to reduce the load with those lightweight filters such as SPF or blacklists.

Comment Re:Useless academic is useless. (Score 1) 462

I did make a typo about the watts/square meter, thank you for the correction. And the risk of focusing a solar sail power beam too strongly, or misdirecting it, _is_ a problem. But it's a similar problem to any abundant energy source. That's a problem of scale, and control, not one of whether the basic technology has ever existed like fusion power. Given the failure to demonstrate even technical feasibility of deriving power from tritium, there's simply no _point_ to investing money in it as a potential power source.

Tritium has research and even medical uses, so potentially mining it from any reasonable source is worth examining. But for power generation, it's clearly pointless..

Comment Re:Useless academic is useless. (Score 2) 462

Since fusion on a stellar scale is already producing approximately 120 watts/square meter to any spot near earth orbit, any outer space program capable of mining the moon is far more capable of erecting solar sails that can use part of the solar wind and light pressure to maintain geosynchronous orbits, even for locations not in the "24-hourorbit" geosynchronous orbit used currently for inexpensive satellite communications and patented by Arthur C. Clarke.

There is simply _no point_ to tritium based fusion powerplants, even with cold fusion, given the expense and rarity of tritium. And certainly there is no point to fusion powerplants when solar power from solar sails is so much less expensive and so much more manageable, with already existing technologies. It's merely an engineering and finance and political problem, not an unsolved scientific one that would have many of the same social problems.Weaponizing fusion is as easy as weaponizing solar sails: the difficulty is _not_ weaponizing fusion power, reguilating it to prevent a catastrophic chain reaction.

Comment Re: Government vs terrorists (Score 2) 395

> There is no need to be terrified of a government where there is democracy and a public that is well informed of its activities.

So you feel that Manning's and Snowden's behavior fostered a well justified fear of the US government, because of the illegal activities they exposed? Especially behavior that was illegal both in US law and was vioaltions of UN treaties which the US signed?

Comment Re:The Power of a Midrange Desktop PC (Score 1) 211

No, I'm afraid that the changing chipsets on many desktop environments make this infeasible. "Suspend" functions, BIOS update tools, multi-monitor setups, and high end graphics still usually run better on Windows (or on MacOS) directly on the hardware. And the virtualization of Windows specific tools like MS Outlook or the VMware management tools or many CAD tools or many higher graphics games is seriously hampered by virtualization.

Linux, conversely, behavior much better in virtualization, so it should normally be used as the virtualizaiton client.

Comment Re:NSA (Score 2) 251

In order to monitor effectively, they need to make sure the is no alternative route, or technology, for the data which they cannot also effectively monitor. This was precisely why they tapped the fiber at the AT&T facilyt in "Room 641" in San Francisco. It's also why telecom companies are forbidden, by law, from using technologies that do not have law enforcement monitoring capacity built in.

So, in your diagram, that "router B" needs to be a core router which cannot evaded by alternative routing or load balancing, such as a security aware customer electing to use a slower, but more secure, router by manipulating their BGP tables. Such hand modification of BGP tables is quite commonplace, for economic and social reasons.

Comment Re:What is the point? (Score 3, Insightful) 79

Knowing where the engineers cluster, and why, can help plan industries or plan job hunting. The clustering also strongly affects engineer salaries and competitive skills, and where to plan conferences of engineering or computer science. And fine granularity can be very helpful for start-up companies, advancing to mid-size companies, who need a larger pool of qualified employees as they move to larger offices.

Conversely, knowing where the _managers_ like to work is important as well. I know competent engineers who literally can get nothing done because their managers call them in for 3 or 4 meetings on the same day, demanding status reports on the projects the engineers would be working on if they weren't in meetings. This is partly because they are in cramped offices where the managers can reach them too easily and keep trying to micromanage the engineers, asking "when will you have a fix for this" and recording it on Gant charts.

Comment Re:The Power of a Midrange Desktop PC (Score 1) 211

With the limited use of Linux for high end graphical tasks, such as gaming, CAD, or Microsoft's locked in tools such as Outlook, it usually makes more sense to run the Windows host as a Windows host directly and run up to half a dozen independent Linux virtual machines on the same host. The well defined virtual environment insulates the desktop or laptop owner from the difficulties of resolving driver issues with whatever chips were added at the last minute, especially if running legacy Linux environments with older kernels for testing or development.

My Macintosh using colleagues and I find leaving the host OS alone, and popping up Linux VM's as needed, to be extremely effective.

Comment Re:NSA (Score 4, Insightful) 251

Given that they did, in fact, cause poor connectivity for critical west coast trunk connections at AT&T with the "bent fiber optic" taps installed in Room 641A, it seems that interfering with a typical customer's bandwidth is not their highest priority. While there are ways in many environments to tap data surreptitiously and at full bandwidth, such setups are often quite expensive and instead done with less sophisticated, possibly slower devices and bandwidth throttled to allow full data capture.

I've certainly seen this in industry when monitoring a network problem, where we throttled the bandwidth so our monitors could keep up and analyze who was abusing our systems.

Comment Re:light, tunnel, oncoming train (Score 2) 248

Personally, I know many of them who will need that Social Security immediately. Some have moved fiscally up to management, and are in better shape fiscally, but many have been relegated down to "legacy support" or squeezed out of their companies to avoid retirement benefits, or have been working as contractors (which makes savings harder). Many of us were horribly battered financially by the dotcom bubble, and others by the housing market crisis where our savings and housing investments collapsed. Being out of work for a year, unplanned, while their "stock options" turned into so much wastepaper collapsed a lot of savings. It's been difficult for many of my older colleagues to keep their skills active and salaries in the middle class, especially if we lost businesses in the dotcom crash and had to start over. Others of us have invested heavily in families and communities, whether with direct finances or by doing careers that we loved, or have health issues that are eating their finances.

The combination of any or all of these has been fiscally devastating to many of my colleagues and predecessors. I've been very fortunate that my workplace values the experience and that the variety of systems we work with keeps my skills fresh. But many of my older technical colleagues have basically become unemployable, since they're "overqualified". And despite its illegality, age discrimination is still widespread, just as there is gender discrimination against hiring women who might become pregnant in IT.

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