The level of security depends on two distinct types of
solutions because there are two kinds of connections. In
a Point-to-Point (P2P) connection the communication is
among nodes of the same PAN and here it is possible to
use the CoAP ncryption and SAFER+ for Bluetooth. This
connection is used also to connect all the nodes of a PAN
to the router. In a Point-to-Internet (P2I) connection the
communication is between the router of the PAN and the
server and in this case it is possible to use the same security
modes but there is another possibility i.e. IPsec. The security
on the CoAP layer has 3 modes (Security section of IEFT
CoAP 11 [20]):