ST87M01 - DTLS persistent Socket during PSM?

[GeoP]

Hi all, 
for minimum wake time I want to use UDP with DTLS.

However, I wonder if it is OK to keep the Socket open for a longer time (not closing it ever)? Even during PSM?

Opening the DTLS-Sockets costs 2 seconds (handshake) and energy, for a Raw-Socket it is almost zero

DTLS: Init->Wait->Use
[000000]> AT#SOCKETCREATE=5,0,UDP,0,60,60,9,0,0
[000116]< #SOCKETCREATE: 0
[000118]< OK
[000000]> AT#DTLSCONNECT=5,0,xxx.xxx.xxx.xxx,pppp
[002011]< #TLS: 3,0x00A8,2048,0
[002012]< OK
[000000]> AT#IPSENDUDP=5,0,xxx.xxx.xxx.xxx,pppp…


Raw
[000011]< #SOCKETCREATE: 0
[000012]< OK
[000000]> AT#IPSENDUDP=5,0,xxx.xxx.xxx.xxx,pppp…

Thanks for any helpful infos,
Jo