Anti-Spam Measures

Although I haven’t been active on this blog for a couple of months, the stream of spam comments and trackbacks hasn’t decreased at all. In fact, I think it has intensified in the last couple of weeks. I don’t have the exact numbers, but I estimate that there were around 300 spam messages in the last 2 months – an average of 5 per days.

I got tired of deleting the comments, or marking them as spam for akismet to handle them, so I decided to install a few extra wordpress plug-ins to do the job for me:

• Akismet. This plug-in is actually installed by default, but you need to activate it manually. When activated, it sends every message received at this blog to a central akismet server for analysis. Since the central server receives thousands of messages, it has the power to compare each message from this blog with thousands of other messages, and to pick up trends of comment spam in real time.
• Bad Behavior. The ultimate gateway filter. Bad Behavior analyzes incoming http requests for common patterns of behavior that are typical of automated bots and other malicious software.
• Challenge. This plug-in is responsible for the math challenge that you now face if you wish to leave a comment. Its purpose, like the captcha, is to verify that you really are a human being, and not an automated program.
• Simple Trackback Validation. Some spam messages arrive as trackbacks rather than as comments. This plug-in follows a simple logic: when a trackback is received, it retrieves the web page located at the URL used in the trackback and checks if the page contains a link to this blog; if there is no link, then it is a spam message.

I could have installed more plug-ins (there are lots to choose from), but I don’t think it would change much. You might have noticed that the plug-ins listed above are all complementing each other. Each plug-in handles a certain aspect of spam filtering that the others don’t, thus I hope that by combining them together I’ll have a spam-proof filter that is stronger than each of them alone.

I couldn’t find any more plug-ins to add that won’t replicate any functionality that I already have. For example, adding a captcha plug-in for submitting comments probably won’t do much, as it replicates the functionality already provided by Challenge.

However, one might claim that there is never “too much” when fighting spam (just like there is never enough security), but that is not true. Answering both a math question and facing a captcha (and whatever else will come next) is a nuisance that hinders usability. Therefore, as a general rule, one needs to think carefully how much benefit a new plug-in provides to the system before adding it.
Hopefully with these plug-ins spam would be history, or at least it would become a manageable problem.

Nature’s Capital II – The Moo Factor

A while back I posted my thoughts about the progress trap – a theme that runs through almost everything that we do today. Simply stated, as we make progress and improve the manageability of our lives in the large scale, we reach (or have reached) a point of diminishing returns, as we exhaust too many environmental resources along the way. By over exhausting those resources, we are living off nature’s capital, instead of living of nature’s interest.

(to see this visually, take the ecological footprint test).

I claimed that one reason for which I choose to avoid meat is because of its negative environmental impact. When describing this idea to friends and acquaintances here in Israel (but only when they ask me first), I often face a very harsh resistance and an expression of disbelief. A lot of people, some of which are highly supportive of green movements, don’t see the connection. Most of them simply aren’t aware of the facts, so I figured perhaps it is worth a while to elaborate on this issue a bit more, and what a better place for this than this blog?

(You see, in the real world, unlike in this blog, there is the issue of timing. Usually, people ask me about this topic exactly when they serve meat at the dinner table. It happened a few times when my dad and I were invited for a Friday night dinner. I then start twitching and turning uncomfortably in my chair as they are eating their turkey and I am supposed to lecture about environmentalism. Although pushing guilt-trips over others is a well-known Jewish trait, it’s not as fun as it sounds, especially not when you are a guest, and sometimes amongst the youngest at the table )

There was an article in Haaretz a couple of months ago exactly about this subject. I wish everyone would read it. Unfortunately, I couldn’t find an English version of it. The article’s bottom line: switching to a veggie diet helps the environment more than switching to a Toyota Prius.

Why is it that a meat-based diet is more harmful than a veggie-based diet? lets look at a source close to home – our friends at veg.ca. They write:

Farm animals naturally inefficient … Like us, animals are naturally inefficient because much of their food is converted into energy for movement, excreted as manure, or used for the growth of body parts not eaten by people. Very little can become direct edible weight gain. For example, cattle excrete 40 kilograms of manure for every kilogram of edible beef produced.

Combine the fact from the last sentence, together with the fact that meat production have increased almost fourfold in four decades, and we are in deep shit! … sorry, I couldn’t resist

In a previous comment, my friend Jorge wrote something similar:

Consumption of resources at the end of the food chain is less energy-efficient than consumption of resources at the beginning of it, since end-of-chain beings spend a good deal of energy just staying alive.

The energy spent by end-of-chain beings, i.e., livestock, can be categorized as follows:

• Use of land;
• Use of water;
• Use of energy, for example, the use of electricity for heating;
• Pollution, produced both by the animals themselves and by the operating cost incurred by the use of energy.

It worth examining to details each of those categories. I’ll try to do so in a later post. Meanwhile, here are a couple of additional references:

1. This is a futuristic article by Guy Dauncey. If you are into computer science, you might recognize a similarity in spirit to this article.
2. If you are a vegetarian, you are in good company