This is a question I received in email. Posting it here for everyone to benefit.
Q: Juniper EX Switch does not send service-type, so how can ISE detect a MAB versus an 802.1X authentication.
A: Attaching a screen shot & a NAD profile for ISE 2.0+.
Note: As of the time of this posting, Juniper EX switches were not tested by the ISE QA team & therefore are not listed in the compatibility matrix here: Cisco Identity Services Engine Network Component Compatibility, Release 2.0 - Cisco