User Agent

This is a self-identification string that a software application sends to a web server

GET / HTTP/1.1
Host: example.com
Headers:
	User-Agent: ztfp-client/1.0     <<<<<<<
	Authorization: Bearer valid:alice
	Accept-Encoding: gzip
      

Types of UA

UA String Description
ztfp-client/1.0 UA belongs to the IBM z/TPF (Transaction Processing Facility) system
z/TPF is a high-performance operating system used primarily by industries that handle massive volumes of transactions in real-time, such as airlines (for reservations) and large financial institutions.
When you see ztfp-client/1.0, it indicates that an application running on an IBM mainframe is making an automated HTTP request to a web service.
Mozilla/5.0 (Windows NT 10.0; Win64; x64)
AppleWebKit/537.36 (KHTML, like Gecko)
Chrome/123.0.0.0 Safari/537.36
Chrome (Windows)
curl/7.68.0 cURL command line tool