SPWF01Sxxx use modes

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If verification fails (either for signature verification error, time or domain mismatch), then the

client throws a warning message “ERROR: SSL/TLS unable to connect” and the connection

is closed. As such, to solve this connection error, users either need to turn off verification of

the server (i.e switch to anonymous mode; see Section 2.4.1), or load the correct CA

certificate.

Note:

The one-way authentication works with any cipher reported in Table 2, including all ECC

ciphers up to 521 key length, RSA-1024 and RSA-2048.

Note:

The maximum allowed size for files uploaded to module is approximately 1.3 KB.

After the client is configured as in Figure 6, the host can open a secure socket.

Figure 6. AT commands for one-way authentication

2.4.3

Mutual authentication

In mutual authentication mode, both parties (client and server) share their signed

certificates.

In order to verify server certificate, the client:

1.

verifies the digital signature

2.

checks that the date of the certificate is in range

3.

verifies the domain

Additionally, for client authentication, the client also:

4.

sends its certificate to the server. Be aware that, in order to verify the client certificate,

the server should have access to the issuing CA certificate (public or private).

To achieve this purpose, the following steps must be completed: