Seokseong Jeon,
Your summary captures some of the differences between the USRP's. If
you haven't already, take a look at the link below for more details.
One thing to note is the USRP2 has been discontinued in favor of the
N200/N210 series.
http://www.ettus.com/faq
If you are interested i
There are various kind of USRP series, USRP1, USRP2, E100, B100, and N200.
At a glance I could find some differences between them.
1. USB connection and Ethernet connection which determines the data rate
between the USRP and a PC.
(and it also makes difference when addressing USRP in GNU Radio.)
