In NSA parlance, a "selector" primarily is a string that semi-uniquely identifies and addresses a persons intercepted data, such as
- an IP address,
- an email address,
- a phone number,
- a SIM card's MSIN
- a person's social security number,
- a national ID card number,
- a passport number,
- a social media handle etc.
(elsewhere also known as "accessor", "key", "handle" or "index")
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