<story><title>Facebook agreed to censor posts after Vietnam slowed traffic – sources</title><url>https://www.reuters.com/article/us-vietnam-facebook-exclusive/exclusive-facebook-agreed-to-censor-posts-after-vietnam-slowed-traffic-sources-idUSKCN2232JX</url></story><parent_chain><item><author>londons_explore</author><text>Undersea cable &lt;i&gt;is&lt;/i&gt; pretty unreliable.  Most major cables expect to break every few years.&lt;p&gt;Usually breaks are caused by humans (ships pulling anchors, sabotage&amp;#x2F;spying).  Sometimes they&amp;#x27;re natural (caused by wildlife, ocean floor movement, flaws in the cable design).&lt;p&gt;Fixes usually take a few hours if they happen at the endpoints, or weeks if they happen somewhere under the ocean.&lt;p&gt;Interestingly, spying breaks always involve &lt;i&gt;three&lt;/i&gt; simultaneous breaks in the cable.  The cable is broken at two points, and then broken at a third point in the middle to put spy equipment.  They do this so the people operating the cable can&amp;#x27;t tell where the spy equipment was inserted, since otherwise you can tell where a cable is broken or being tampered with by sending light down the cable and seeing how long before light reflects off the broken bit and comes back to the end.&lt;p&gt;Using statistical methods, you can see how frequently you&amp;#x27;d expect a cable to break at different points along it&amp;#x27;s length simultaneously, and it happens a lot more than raw chance would suggest.</text></item><item><author>NhanH</author><text>Just tangentially related to the topic at hand, but I have a question to ask HN.
The main trans-Pacific cable connection between Vietnam and the US tends to be damaged several times a year (3&amp;lt;n&amp;lt;10 is my guess), which severely slow downs any connection to the outside of Vietnam during the time it is under maintenance. This always happens suspiciously during major political holiday (Independence day and the likes), so Vietnamese has just assumed that is a blatant censorship attempt. The wiki page has an outage section you can read: &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Asia-America_Gateway&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Asia-America_Gateway&lt;/a&gt; , it doesn&amp;#x27;t list anything beyond 2018, but the situation is the same.&lt;p&gt;So my question is, how likely it is that the cable system are just really shitty? Or is the assumption of bald-faced censorship correct?</text></item></parent_chain><comment><author>bogomipz</author><text>&amp;gt;&amp;quot;Undersea cable is pretty unreliable.&amp;quot;&lt;p&gt;This is not true. Submarine cable installations generally have a lifespan of 20-25 years although that&amp;#x27;s even being extended now to 30 years with advances in WDM gear. Also in water deeper than 1500 meters the cables are typically laid on the ocean floor. This is done because it is beyond the limit of trawl fishing anchors.&lt;p&gt;&amp;gt;&amp;quot;Interestingly, spying breaks always involve three simultaneous breaks in the cable. The cable is broken at two points, and then broken at a third point in the middle to put spy equipment.&amp;quot;&lt;p&gt;Yeah this is not true at all. Where did you get this from? Fiber cables can be tapped by simply adding a bend radius to the cable which allows it to leak. [1], Further you can shoot a light down both ends of a fiber and easily discern that there is more than one break in the cable.&lt;p&gt;[1] &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.thefoa.org&amp;#x2F;tech&amp;#x2F;ref&amp;#x2F;appln&amp;#x2F;tap-fiber.html&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.thefoa.org&amp;#x2F;tech&amp;#x2F;ref&amp;#x2F;appln&amp;#x2F;tap-fiber.html&lt;/a&gt;</text></comment>
<story><title>Facebook agreed to censor posts after Vietnam slowed traffic – sources</title><url>https://www.reuters.com/article/us-vietnam-facebook-exclusive/exclusive-facebook-agreed-to-censor-posts-after-vietnam-slowed-traffic-sources-idUSKCN2232JX</url></story><parent_chain><item><author>londons_explore</author><text>Undersea cable &lt;i&gt;is&lt;/i&gt; pretty unreliable.  Most major cables expect to break every few years.&lt;p&gt;Usually breaks are caused by humans (ships pulling anchors, sabotage&amp;#x2F;spying).  Sometimes they&amp;#x27;re natural (caused by wildlife, ocean floor movement, flaws in the cable design).&lt;p&gt;Fixes usually take a few hours if they happen at the endpoints, or weeks if they happen somewhere under the ocean.&lt;p&gt;Interestingly, spying breaks always involve &lt;i&gt;three&lt;/i&gt; simultaneous breaks in the cable.  The cable is broken at two points, and then broken at a third point in the middle to put spy equipment.  They do this so the people operating the cable can&amp;#x27;t tell where the spy equipment was inserted, since otherwise you can tell where a cable is broken or being tampered with by sending light down the cable and seeing how long before light reflects off the broken bit and comes back to the end.&lt;p&gt;Using statistical methods, you can see how frequently you&amp;#x27;d expect a cable to break at different points along it&amp;#x27;s length simultaneously, and it happens a lot more than raw chance would suggest.</text></item><item><author>NhanH</author><text>Just tangentially related to the topic at hand, but I have a question to ask HN.
The main trans-Pacific cable connection between Vietnam and the US tends to be damaged several times a year (3&amp;lt;n&amp;lt;10 is my guess), which severely slow downs any connection to the outside of Vietnam during the time it is under maintenance. This always happens suspiciously during major political holiday (Independence day and the likes), so Vietnamese has just assumed that is a blatant censorship attempt. The wiki page has an outage section you can read: &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Asia-America_Gateway&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Asia-America_Gateway&lt;/a&gt; , it doesn&amp;#x27;t list anything beyond 2018, but the situation is the same.&lt;p&gt;So my question is, how likely it is that the cable system are just really shitty? Or is the assumption of bald-faced censorship correct?</text></item></parent_chain><comment><author>oldsklgdfth</author><text>I was under the impression that underwater cables were fairly reliable, but it seems they require frequent repair.&lt;p&gt;Per wikipedia:
&amp;gt; Still, cable breaks are by no means a thing of the past, with more than 50 repairs a year in the Atlantic alone,[48] and significant breaks in 2006, 2008, and 2009.</text></comment>