How do Juniper Networks compete with Cisco?

I would say Juniper, since both are widely used allover the world, I personally like the detailed log messages in juniper they make troubleshooting easy. 

Juniper JunOS software is reliable and unified for all paltforms. 

also hardrdware is powerfull, and reliable. 

i think Juniper Firewalls SRX is better than ASA.

I think cisco networks are widly used , 

Assalamu,Alleikum, . In fact Cisco is I would say worldwide, Although Juniper got some share of the deployment. among other such as HP. when considering standards and inter-operation its easy to go with Cisco.