beautypg.com

Digital signatures – Nokia 5140 User Manual

Page 60

background image

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.

• User certificates are issued to users by a certifying authority. User certificates are required, for example, to create a digital

signature, and they associate the user with a specific private key in a security module.

To view user certificates, press

Menu

, and select

Services

Settings

Security settings

User certificates

Certificate

list

.

• Authority certificates are used by some services, such as banking services, to check the validity of other certificates.

Authority certificates can either be saved in the security module by the service provider, or they can be downloaded from
the network, if the service supports their use.

To view authority certificates, press

Menu

, and select

Services

Settings

Security settings

Authority certificates

Certificate list

.

Digital signatures

You can create digital signatures with your phone. The signature can be traced back to you by the private key in the security
module and the user certificate that was used to perform the signature. Using the digital signature is similar to signing your
name to a paper bill, contract, or other document.

To create a digital signature, select a link on a page, for example, the title of a book that you want to buy and its price. The
text to sign (including, for example, the amount and date) will be 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, then select

Sign

.

Note that the text may not fit on a single screen. Therefore, make sure to scroll through and read all of the text before
signing.

Select the user certificate that you want to use. Key in the signing PIN, and press

OK

. The digital signature icon disappears,

and the service may display a confirmation of your purchase.

S e r v i c e s

Copyright © 2004 Nokia. All Rights Reserved.

60