On Jan. 1, millions of Internet users around the world will find it difficult to connect to many websites because of expiring encryption technology.

Technology insiders are calling the changeover to the new encryption technology the "SHA-1 Sunset," CNBC reports.

In 2016, many devices with technology older than SHA-1 level encryption will not meet the security requirements of many websites. As many as 37 million people could be without access to most websites. 

The update is routine for most Internet users, but many people in developing countries with older devices will be majorly affected. Older mobile devices in these countries will have the most trouble. Users with devices that are older than five years or with old software will see error messages when trying to connect to many sites that are unencrypted.  

Sites that do not have these safety protocols will still be reachable, but such sites could also be vulnerable to attacks and identify theft.

Secure websites will automatically change to the "https" prefix on most computers, but those with older technology do not get that benefit. Older operating systems and web browsers, like Microsoft Windows XP and older versions of Internet Explorer, will not be able to give encrypted versions of websites.

Old cellphones, which may have been used by Americans years ago, often find their way into developing countries, where residents do not have adequate access to the Internet. These devices will also experience difficulties starting on Jan. 1.

Companies will start offering incentives to get people to upgrade to newer cellphones and technology, but in many of these countries, people lack the necessary funds to upgrade to new technology.

The new SHA-2 level encryption will be needed to access most sites in 2016. Security experts say encryption is very important, after many websites and retailers have seen their websites hacked in the last two years.