There has been a lot of talk about STIR/SHAKEN in the news lately, but what is this strange system? The answer is actually less complicated then it seems. Essentially, STIR/SHAKEN is a system developed to help combat criminal robocalls and caller ID spoofing. Still confused? Let's start at the beginning. 

Currently, scammers can change the number they're using to call with to make it appear as if someone friendly is calling. This is called spoofing. This kind of scam is highly illegal and is used to steal information and money (for example, a caller may impersonate a tax agency representative in order to steal your tax refund). 

What STIR/SHAKEN does is validate phone calls as they travel through the phone networks, which allows phone companies and consumers to be sure the call they're receiving is from legitimately from the person making it. 

• The STIR part is the technology behind the idea. It stands for Secure Telephony Identity Revisited and is the central certificate authority. It essentially gives digital certificates to each phone service provider that allows them to verify if the call coming through their system is legitimate. 
• SHAKEN is the protocol that outlines how service providers can use the STIR technology. SHAKEN stands for Secure Handling of Asserted information using toKENs). These two components work together in tandem to help increase the security of our phone lines. 

When a call begins on a network, the service provider uses the STIR tech to create a SIP Identity Header. This includes information such as date, time and phone numbers involved. Most importantly, it includes an attestation level which is a level of confidence indicator. There are 3 levels of attestation based on the level of verification the company is able to achieve. 

• Full Attestation means the person making the call and their number are legitimate. 
  Partial Attestation means the person making the call is legitimate, but they can't verify if they're authorized to use that number. 
• Gateway Attestation means the service provider can verify where the call is coming from but can't verify the person making the call. 

Overall, STIR / SHAKEN helps everyone by making our phone lines a safer and more authentic form of communication.