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	<title>Calcifer &#187; networks</title>
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		<title>The impact of social networking on society</title>
		<link>http://blog.calcifer.com.ar/2006/09/the-impact-of-social-networking-on-society/</link>
		<comments>http://blog.calcifer.com.ar/2006/09/the-impact-of-social-networking-on-society/#comments</comments>
		<pubDate>Thu, 21 Sep 2006 20:08:10 +0000</pubDate>
		<dc:creator>lvidarte</dc:creator>
				<category><![CDATA[None]]></category>
		<category><![CDATA[networks]]></category>

		<guid isPermaLink="false">http://blog.calcifer.com.ar/2006/09/21/the-impact-of-social-networking-on-society/</guid>
		<description><![CDATA[From New Scientist Print EditionBy Sherry TurkleVía Slashdot
Is social networking changing the way people relate to each other?
For some people, things move from &#8220;I have a feeling, I want to call a friend&#8221; to &#8220;I want to feel something, I need to make a call&#8221;. In either case, what is not being cultivated is the [...]]]></description>
			<content:encoded><![CDATA[<p class="from">From <a href="http://www.newscientisttech.com/article/mg19125691.600" title="" class="linkexternal">New Scientist Print Edition</a><br />By Sherry Turkle<br />Vía <a href="http://yro.slashdot.org/article.pl?sid=06/09/20/1325238&#038;from=rss" title="" class="linkexternal">Slashdot</a></p>
<h3>Is social networking changing the way people relate to each other?</h3>
<p>For some people, things move from &#8220;I have a feeling, I want to call a friend&#8221; to &#8220;I want to feel something, I need to make a call&#8221;. In either case, what is not being cultivated is the ability to be alone and to manage and contain one&#8217;s emotions. When technology brings us to the point where we&#8217;re used to sharing our thoughts and feelings instantaneously, it can lead to a new dependence, sometimes to the extent that we need others in order to feel our feelings in the first place.</p>
<p>Our new intimacies with our machines create a world where it makes sense to speak of a new state of the self. When someone says &#8220;I am on my cell&#8221;, &#8220;online&#8221;, &#8220;on instant messaging&#8221; or &#8220;on the web&#8221;, these phrases suggest a new placement of the subject, a subject wired into social existence through technology, a tethered self. I think of tethering as the way we connect to always-on communication devices and to the people and things we reach through them.</p>
<h3>How is it affecting families?</h3>
<p>Let me take a simple example. Tethered adolescents are given a cellphone by their parents. In return, they are expected to answer their parents&#8217; calls. On the one hand, this arrangement gives the adolescent new freedoms. On the other, the adolescent does not have the experience of being alone, of having only him or herself to count on: there is always a parent on speed dial. This provides comfort in a dangerous world, yet there is a price to pay in the development of autonomy. There used to be a moment in the life of an urban child, usually between the ages of 12 and 14, when there was a first time to navigate the city alone. It was a rite of passage that communicated, &#8220;You are on your own and responsible.&#8221; Tethering via a cellphone buffers this moment; tethered children think differently about themselves. They are not quite alone.</p>
<p><span id="more-50"></span></p>
<h3>Does it worry you?</h3>
<p>Our society tends toward a breathless techno-enthusiasm: &#8220;We are more connected; we are global; we are more informed.&#8221; But just as not all information put on the web is true, not all aspects of the new sociality should be celebrated. We communicate with quick instant messages, &#8220;check-in&#8221; cell calls and emoticon graphics. All of these are meant to quickly communicate a state. They are not meant to open a dialogue about complexity of feeling. Although the culture that grows up around the cellphone is a &#8220;talk culture&#8221;, it is not necessarily a culture that contributes to self-reflection. Self-reflection depends on having an emotion, experiencing it, taking one&#8217;s time to think it through and understand it, but only sometimes electing to share it.<br />
Is this a bad thing?</p>
<p>The self that grows up with multitasking and rapid response measures success by calls made, emails answered, messages responded to. In this buzz of activity, there may be losses that we are not ready to sustain. We insist that our world is increasingly complex, yet we have created a communications culture that has decreased the time available for us to sit and think, uninterrupted. Teens growing up with always-on communication are primed to receive a quick message to which they are expected to give a rapid response. They may never know another way. Their experience raises a question for us all: are we leaving enough time to take one&#8217;s time?</p>
<h3>Are you talking about a permanent change?</h3>
<p>It seems to be part of a larger trend in media culture for people not to know what they think until they get a sense of what everyone else thinks. But we learn about what everyone else thinks by reading highly polarised opinions that encourage choosing sides rather than thinking things through. You can give media culture a positive spin and say that people are more socially enmeshed, but it has a darker side: as a feeling emerges, people share the feeling to see if they have the feeling. And sometimes they don&#8217;t have the feeling until they check if other people have it too. This kind of behaviour used to be associated with early adolescents, with their need for validation. Now always-on technology is turning it into a norm.<br />
&#8220;A question for us all: are we leaving enough time to take one&#8217;s time?&#8221;</p>
<h3>Surely being socially enmeshed can also have a positive side?</h3>
<p>The challenge for this generation is to think of sociality as more than the cyber-intimacy of sharing gossip and photographs and profiles. This is a paradoxical time. We have more information but take less time to think it through in its complexity. We&#8217;re connecting globally but talking parochially.</p>
<h3>Are you saying that people are missing the broader picture?</h3>
<p>People are connecting one-on-one &#8211; they have their online social network or their cellphone with 250 people on speed dial &#8211; but do they feel part of a community? Do they feel responsibility to a set of shared political commitments? Do they feel a need to take responsibility for issues that would require that they act in concert rather than just connect? Recently, connectivity and statements of identity on places such as Facebook or MySpace have themselves become values. It is a concern when self-expression becomes more important than social action.</p>
<h3>What kind of responsibility are they ducking?</h3>
<p>Summer 2006 finds the world enmeshed in multiple wars and genocidal campaigns. It finds the world incapable of calling a halt to environmental destruction. Yet, with all of this, people seem above all to be fascinated by novel technologies. On college campuses there is less interest in asking questions about the state of the world than in refining one&#8217;s presence on Facebook or MySpace. Technology pundits may talk in glowing terms about new forms of social life, but the jury is out on whether virtual self-expression will translate into collective action.</p>
<h3>Explore the other features in New Scientist&#8217;s guide to the social networking revolution:</h3>
<p><a href="http://www.newscientisttech.com/article/mg19125691.500" title="" class="linkexternal">This is your space</a> – Discover how social networking evolved, how it works and how it is already revolutionising the way we live, socialise and work</p>
<p><a href="http://www.newscientisttech.com/article/mg19125691.700" title="" class="linkexternal">The end of privacy?</a> – You wouldn&#8217;t tell a stranger on the bus about your sexual habits, so why do people reveal this stuff on websites available to everyone? Will their openness return to haunt them?</p>
<p><a href="http://www.newscientisttech.com/article/mg19125691.800" title="" class="linkexternal">I saw the best minds of my generation destroyed by Google</a> – A short story by Bruce Sterling</p>
<p><a href="http://www.newscientisttech.com/article/mg19125691.900" title="" class="linkexternal">The internet could be so much better</a> – Social networking websites like MySpace or YouTube owe everything to the genius of Ted Nelson, who invented hypertext in the 1960s</p>
<p><a href="http://www.newscientisttech.com/article/mg19125692.000" title="" class="linkexternal">Give it a try</a> – Feeling left out of the social networking revolution? There are many ways you can get involved, so take a look</p>
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		<title>El ancho de banda de una camioneta</title>
		<link>http://blog.calcifer.com.ar/2006/09/el-ancho-de-banda-de-una-camioneta/</link>
		<comments>http://blog.calcifer.com.ar/2006/09/el-ancho-de-banda-de-una-camioneta/#comments</comments>
		<pubDate>Thu, 14 Sep 2006 17:30:39 +0000</pubDate>
		<dc:creator>lvidarte</dc:creator>
				<category><![CDATA[cites]]></category>
		<category><![CDATA[humor]]></category>
		<category><![CDATA[networks]]></category>

		<guid isPermaLink="false">http://blog.calcifer.com.ar/2006/09/14/el-ancho-de-banda-de-una-camioneta/</guid>
		<description><![CDATA[Extraído del libro &#8220;Redes de computadoras&#8221;, de Andrew S. Tenembaum:
Una de las formas más comunes para transportar datos de una computadora a otra es almacenarlos en cintas magnéticas o medios extraíbles (por ejemplo, DVD&#8217;s grabables), transportar físicamente la cinta o los discos a la máquina de destino y leer dichos datos ahí. Si bien este [...]]]></description>
			<content:encoded><![CDATA[<p class="from">Extraído del libro &#8220;Redes de computadoras&#8221;, de Andrew S. Tenembaum:</p>
<p>Una de las formas más comunes para transportar datos de una computadora a otra es almacenarlos en cintas magnéticas o medios extraíbles (por ejemplo, DVD&#8217;s grabables), transportar físicamente la cinta o los discos a la máquina de destino y leer dichos datos ahí. Si bien este método no es tan avanzado como utilizar un satélite de comunicaciones geosíncrono, con frecuencia es más rentable, especialmente para aplicaciones en las que un ancho de banda alto o el costo por bit transportado es un factor clave.</p>
<p>Un cálculo simple aclarará este punto. Una cinta <a href="http://en.wikipedia.org/wiki/Ultrium" class="linkwikipedia">Ultrium</a> estándar puede almacenar 200 gigabytes. Una caja de 60 x 60 x 60 cm puede contener aproximadamente 1000 de estas cintas, con una capacidad total de 200 terabytes, o 1600 terabits (1.6 petabis). Una caja de cintas puede enviarse a cualquier parte de los Estados Unidos en 24 horas por Federal Express y otras compañías. El ancho de banda efectivo en esta transmisión es de 1600 terabits/86400 seg o 19 Gbps. Si el destino está a sólo una hora por carretera, el ancho de banda se incrementa a casi 400 Gbps. Ninguna red de computadoras puede superar esto. La moraleja:</p>
<blockquote class="cite"><p>Nunca subestime el ancho de banda de una camioneta que va a toda velocidad por la carretera.</p></blockquote>
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		<item>
		<title>Web server desde una red interna usando SSH</title>
		<link>http://blog.calcifer.com.ar/2006/07/web-server-desde-una-red-interna-usando-ssh/</link>
		<comments>http://blog.calcifer.com.ar/2006/07/web-server-desde-una-red-interna-usando-ssh/#comments</comments>
		<pubDate>Thu, 20 Jul 2006 13:55:10 +0000</pubDate>
		<dc:creator>lvidarte</dc:creator>
				<category><![CDATA[None]]></category>
		<category><![CDATA[gnu/linux]]></category>
		<category><![CDATA[networks]]></category>
		<category><![CDATA[ssh]]></category>

		<guid isPermaLink="false">http://blog.calcifer.com.ar/2006/07/20/web-server-desde-una-red-interna-usando-ssh/</guid>
		<description><![CDATA[Supongamos que tenemos una máquina dentro de una red interna ejecutando un servidor web y queremos que dicho servidor pueda ser accedido desde el exterior. Supongamos también que tenemos una cuenta SSH en el gateway que nos da salida a Internet&#8230; aunque, lamentablemente, no somos su administrador.
La idea es abrir un puerto en el gateway [...]]]></description>
			<content:encoded><![CDATA[<p>Supongamos que tenemos una máquina dentro de una red interna ejecutando un servidor web y queremos que dicho servidor pueda ser accedido desde el exterior. Supongamos también que tenemos una cuenta SSH en el gateway que nos da salida a Internet&#8230; aunque, lamentablemente, no somos su administrador.</p>
<p>La idea es abrir un puerto en el gateway (por encima del 1023) y redireccionar todas las conexiones entrantes al puerto 80 de nuestra máquina interna, que es donde está escuchando nuestro servidor web. Para ello crearemos un túnel SSH entre el gateway y nuestra máquina:</p>
<div class="codecolorer-container text " style="overflow:auto;white-space:nowrap;width:435px"><div class="text codecolorer" style="font-family:Monaco,Lucida Console,monospace">ssh &nbsp;-g -L 10080:localhost:80 usuario@maq_interna -N</div></div>
<p>Este comando debemos ejecutarlo desde el gateway, ya que estamos usando la opción<code>-L</code>(local).</p>
<p>La opción -g (que equivale a &#8216;GatewayPorts yes&#8217; en<code>~/.ssh/config</code>o<code>/etc/ssh/ssh_config</code>) es muy importante, ya que sin ella el túnel sólo estaría disponible para conexiones desde localhost y nosotros queremos que cualquier persona en Internet pueda acceder a nuestro servidor web.</p>
<p>Para comprobar esto basta con ejecutar:</p>
<div class="codecolorer-container text " style="overflow:auto;white-space:nowrap;width:435px"><div class="text codecolorer" style="font-family:Monaco,Lucida Console,monospace">netstat -nlpt</div></div>
<p>Deberíamos ver una línea como la siguiente:</p>
<div class="codecolorer-container text " style="overflow:auto;white-space:nowrap;width:435px"><div class="text codecolorer" style="font-family:Monaco,Lucida Console,monospace">tcp6 &nbsp; &nbsp; &nbsp; 0 &nbsp; &nbsp; &nbsp;0 : : :10080 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; : : : * &nbsp; &nbsp; &nbsp;LISTEN &nbsp; &nbsp; 12414/ssh</div></div>
<p>Lo que nos  indica que el puerto 10080 está escuchando conexiones provenientes desde cualquier dirección y no sólo desde 127.0.0.1.</p>
<p>Por último, la opción<code>-N</code>le indica a SSH que luego de crear el túnel no nos devuelva el prompt del shell.</p>
<p>Listo. Sólo basta abrir un navegador e ingresar:</p>
<div class="codecolorer-container text " style="overflow:auto;white-space:nowrap;width:435px"><div class="text codecolorer" style="font-family:Monaco,Lucida Console,monospace">http://ip_gateway:10080</div></div>
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