CPSNA 2011 is part of RTCSA 2011.
All attendees must register at RTCSA 2011.
The registration will give you access to both CPSNA 2011 and RTCSA 2011.
Hotel discounts are also available upon registration.
More information can be found here.
If you have any additional questions, please feel free to contact the RTCSA organization at rtcsa2011-organizers*at*googlegroups.com (replace *at* with @).