<story><title>Shortening the Let&apos;s Encrypt chain of trust</title><url>https://letsencrypt.org/2023/07/10/cross-sign-expiration.html</url></story><parent_chain><item><author>londons_explore</author><text>I&amp;#x27;m disappointed that we can&amp;#x27;t come up with a way for encryption to work forever.&lt;p&gt;Like, if I find a knife from 150 years ago, it still cuts cheese.   Sure - it isn&amp;#x27;t the most modern tech, but it still does the job it was made for.   Even though cheese recipes have changed, they are still compatible with an old knife.&lt;p&gt;Yet a phone in 150 years will be 100% useless.   Not only useless because other things have moved on, or because the hardware has degraded, but &lt;i&gt;useless by design&lt;/i&gt; because root certificates expire.&lt;p&gt;We shouldn&amp;#x27;t be putting anything into consumer electronics with an expiry date.</text></item><item><author>profmonocle</author><text>Let&amp;#x27;s Encrypt is switching to a different root certificate (their own root certificate), which means that &lt;i&gt;extremely outdated&lt;/i&gt; devices will no longer be able to access servers using Let&amp;#x27;s Encrypt certificates.&lt;p&gt;The biggest concern is old Android devives. By &amp;quot;old&amp;quot;, I mean devices using a version of Android from the Obama administration. Android 7.1 is the oldest version that will work, and it was released on October 4th, 2016.&lt;p&gt;At this point, roughly 6.1% of Android devices are running a version of Android that will be impacted by this change. It&amp;#x27;s likely that most of these devices are in relatively low-income countries, so depending on your audience this may be much lower or much higher. (If your primary audience isn&amp;#x27;t in a developing country, it&amp;#x27;s likely much higher.)&lt;p&gt;This change will affect you at some point after February 8th, 2024. (Specifically, you&amp;#x27;ll be affected the first time your LE cert renews after that point. If you&amp;#x27;re using one of the common clients, it will be up to 60 days after that point.) If you want, you can configure your client to support legacy devices longer, but only up to June 6th, 2024. After then, if you truly need to support very, very old Android devices, you would need to switch from Let&amp;#x27;s Encrypt to a different (possibly paid) CA.&lt;p&gt;Only you know for sure if you need to support these very old devices. Most web sites don&amp;#x27;t.</text></item><item><author>hospitalJail</author><text>Can you explain?&lt;p&gt;I use it and forget Let&amp;#x27;s Encrypt is so critical to my website.</text></item><item><author>profmonocle</author><text>I remember when Let&amp;#x27;s Encrypt announced they were going to do this in summer of 2019. They listened to community feedback and postponed.&lt;p&gt;I really want to shout out the LE team for how they handled this. Back in 2019 I was one of the loud people urging to you to reconsider. You &lt;i&gt;massively&lt;/i&gt; overshot my wildest hopes on this issue - I never expected you to delay this switch for 4 1&amp;#x2F;2 years. That&amp;#x27;s incredible. Thank you for showing this level of care for the TLS ecosystem.</text></item></parent_chain><comment><author>tialaramex</author><text>A knife is an extremely simple tool and you&amp;#x27;re making a very modest requirement of it (that it should cut cheese). There&amp;#x27;s no way that a 2023 smartphone is equivalently simple, nor that &amp;quot;Just access arbitrary remote stuff over the Internet&amp;quot; is a similarly modest requirement.&lt;p&gt;Lets try something appreciably more complex and do an equivalently tricky task. Lets use an 1873 steam train to travel from London to Derby.&lt;p&gt;We run into more or less the same problem. Functionally, this can work, you&amp;#x27;ll have to buy the coal from somewhere and hire tankers to move the water where it&amp;#x27;s needed since there is no longer provision for that- but much harder you&amp;#x27;ll need to secure an extraordinary amount of special case paperwork to make this happen, because obviously your 1873 steam train isn&amp;#x27;t authorized to use this route, you will need to retro-fit safety equipment that an 1873 steam train was never designed to work with, and you will need to re-train people to operate it.&lt;p&gt;Don&amp;#x27;t worry though, you have preserved the important part - your 150 year old train &lt;i&gt;is&lt;/i&gt; still ludicrously unsafe compared to its modern equivalent like the phone. Relatively minor impacts will turn the passenger compartments into kindling, with passengers still inside, because they&amp;#x27;re basically just a wooden box resting on a simple metal platform, not a monocoque design and even after fitting mandatory safety equipment the train can&amp;#x27;t effectively stop anywhere close to fast as modern trains if things go wrong.</text></comment>
<story><title>Shortening the Let&apos;s Encrypt chain of trust</title><url>https://letsencrypt.org/2023/07/10/cross-sign-expiration.html</url></story><parent_chain><item><author>londons_explore</author><text>I&amp;#x27;m disappointed that we can&amp;#x27;t come up with a way for encryption to work forever.&lt;p&gt;Like, if I find a knife from 150 years ago, it still cuts cheese.   Sure - it isn&amp;#x27;t the most modern tech, but it still does the job it was made for.   Even though cheese recipes have changed, they are still compatible with an old knife.&lt;p&gt;Yet a phone in 150 years will be 100% useless.   Not only useless because other things have moved on, or because the hardware has degraded, but &lt;i&gt;useless by design&lt;/i&gt; because root certificates expire.&lt;p&gt;We shouldn&amp;#x27;t be putting anything into consumer electronics with an expiry date.</text></item><item><author>profmonocle</author><text>Let&amp;#x27;s Encrypt is switching to a different root certificate (their own root certificate), which means that &lt;i&gt;extremely outdated&lt;/i&gt; devices will no longer be able to access servers using Let&amp;#x27;s Encrypt certificates.&lt;p&gt;The biggest concern is old Android devives. By &amp;quot;old&amp;quot;, I mean devices using a version of Android from the Obama administration. Android 7.1 is the oldest version that will work, and it was released on October 4th, 2016.&lt;p&gt;At this point, roughly 6.1% of Android devices are running a version of Android that will be impacted by this change. It&amp;#x27;s likely that most of these devices are in relatively low-income countries, so depending on your audience this may be much lower or much higher. (If your primary audience isn&amp;#x27;t in a developing country, it&amp;#x27;s likely much higher.)&lt;p&gt;This change will affect you at some point after February 8th, 2024. (Specifically, you&amp;#x27;ll be affected the first time your LE cert renews after that point. If you&amp;#x27;re using one of the common clients, it will be up to 60 days after that point.) If you want, you can configure your client to support legacy devices longer, but only up to June 6th, 2024. After then, if you truly need to support very, very old Android devices, you would need to switch from Let&amp;#x27;s Encrypt to a different (possibly paid) CA.&lt;p&gt;Only you know for sure if you need to support these very old devices. Most web sites don&amp;#x27;t.</text></item><item><author>hospitalJail</author><text>Can you explain?&lt;p&gt;I use it and forget Let&amp;#x27;s Encrypt is so critical to my website.</text></item><item><author>profmonocle</author><text>I remember when Let&amp;#x27;s Encrypt announced they were going to do this in summer of 2019. They listened to community feedback and postponed.&lt;p&gt;I really want to shout out the LE team for how they handled this. Back in 2019 I was one of the loud people urging to you to reconsider. You &lt;i&gt;massively&lt;/i&gt; overshot my wildest hopes on this issue - I never expected you to delay this switch for 4 1&amp;#x2F;2 years. That&amp;#x27;s incredible. Thank you for showing this level of care for the TLS ecosystem.</text></item></parent_chain><comment><author>i_am_proteus</author><text>The encryption itself will work &amp;quot;forever.&amp;quot; (Realistically, very powerful computers could some day obviate contemporary encryption).&lt;p&gt;The tricky part about PKI and signed TLS certificates has little to do with the encryption and a lot to do with networks of trusted parties.  People die and are born, relationships evolve, and so these networks are inherently dynamic.&lt;p&gt;Certificate expiration is a feature by design, and it&amp;#x27;s included for a reason.</text></comment>