User's Manual

Table Of Contents
Secure Socket Protocol
AT+i Programmer‘s Manual Version 8.32 21-2
AT+iSTCP:secure.sslserver.com,1503
Open a TCP/IP socket to a
secure application.
I/000
iChip opens socket and returns
handle 0.
AT+iSSL:0
iChip is instructed to negotiate
an SSL3/TLS1 connection on
socket handle 0.
I/OK
SSL3/TLS1 handshake was
successful. SSL3/TLS1
connection established on socket
handle 0.
AT+iSSND%:0,323:<…323 bytes of plain text data>
Host sends 323 bytes of plain
text data via SSL3/TLS1 socket.
iChip encrypts data and sends
cipher text over the Internet. The
‗%‘ attribute indicates
immediate flush.
I/OK
iChip encrypted and sent data.
AT+iRP4
Request socket status
I/(1267,-200,-200,-200,-200,-200,-200,-200,
-200,-200)
Socket 0 has 1267 plain text
bytes buffered. The data was
originally sent encrypted by the
server. iChip decrypted the
cipher text in the background.
AT+iSRCV:0
Command to retrieve buffered
plain text.
I/1267:<…1267 bytes of plaintext data…>
iChip transmits buffered data to
host.
AT+iscls:0
Close socket handle 0
I/OK
SSL3/TLS1 socket is closed
I/DONE
iChip is offline
21.4 Secure FTP Session on iChip
iChip supports a secure FTP session using SSL3/TLS1 sockets for both the FTP
command and FTP data channels. The command used for opening a secure FTP session is
AT+iFOPS.
Secure FTP implementation in iChip is based on RFC 2228 (FTP security extensions) and
the IETF Internet draft ―Securing FTP with TLS‖ (draft-murray-auth-ftp-ssl-16.txt).