PIISUSER for certificate uthentication

http://scn.sap.com/community/pi-and-soa-middleware/blog/2013/09/20/sender-soap-adapter-https-with-client-authentication

HI frends

I am following this blog. I don't see PIISUSER in my PO system. Instead I can see PIIS<SID> user. Is that user same as PIISUSER?

Also I don't see the parameter ume.logon.allow_cert when I go to NWA-->Configuration-->Authentication and Single SignOn

I need the Certificates tab next to the user

Am working in SAP PI single stack 7.3 service pack 8

Harish