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authentic, or trusted certificates for increased security to be available. Certificates have a
restricted lifetime. If "Expired certificate" or "Certificate not valid yet" is shown even if the
certificate should be valid, check that the current date and time in your device are correct.
Before changing any certificate settings, you must make sure that you really trust the owner
of the certificate and that the certificate really belongs to the listed owner.
There are three kinds of certificates: server certificates, authority certificates, and
user certificates. You may receive these certificates from your service provider.
Authority certificates and user certificates may also be saved in the security
module by the service provider.
To view the list of the authority or user certificates downloaded into your phone,
select Menu> Settings > Security > Authority certificates or User certificates.
is displayed during a connection, if the data transmission between the
phone and the content server is encrypted.
The security icon does not indicate that the data transmission between the gateway and the
content server (or place where the requested resource is stored) is secure. The service
provider secures the data transmission between the gateway and the content server.
Digital signature
You can make digital signatures with your phone if your SIM card has a security
module. Using the digital signature can be the same as signing your name to a
paper bill, contract, or other document.
To make a digital signature, select a link on a page, for example, the title of the
book you want to buy and its price. The text to sign, which may include the
amount and date, is shown.
Check that the header text is Read and that the digital signature icon is
shown.
If the digital signature icon does not appear, there is a security breach, and you
should not enter any personal data such as your signing PIN.
To sign the text, read all of the text first, and select Sign.
The text may not fit within a single screen. Therefore, make sure to scroll through
and read all of the text before signing.
Select the user certificate you want to use. Enter the signing PIN. The digital
signature icon disappears, and the service may display a confirmation of your
purchase.