[OMPI users] requirement on ssh when run openmpi

[meng]

Hi all,
   what 's the requriement, especially on ssh, to run openmpi? I have two 
computers, say c1 and c2. Through ssh, c1 can access c2 without password, but 
c2 can't access c1. Under this environment, can I use openmpi to compute 
parallely? 
 Regards,
meng