Technical information

Secure Socket Protocol Theory of Operation
2-96 AT+i Commands Reference Manual May 31, 2008
Creating a Certificate Authority
The certificate generated using the following steps can be used in deployed systems, in which you
are the trusted authority. Users of these certificates can be confident of your identity. For
example, W24 devices communicating with servers that are setup and configured by the device
vendor can secure their communications using certificates signed by the vendor-created
Certificate Authority.
In order to store the files to be generated, create a new directory named testCA.
Open a command will (on Windows, enter cmd in the Start > Run dialog box), change the
command shell's working directory to testCA and follow these instructions:
Creating the CA Environment
The creation of a CA produces several files that must be preserved throughout the lifecycle of the
CA. You can sign an unlimited number of certificates using a single CA. These files are written to
each time you sign a certificate.
1. Under the testCA directory create sub-directories certs and private.
2. Create a new file named serial. In this file enter the numerals '01' and save the file.
3. Create an empty file named index.txt.
Creating the Test CA Configuration File
Whereas you can enter all configuration information in a command line, creating a configuration
file makes these steps easier to reproduce and allows you to save the options used to create a CA.
1. Create a new file named CAcnf.ca using a text editor of your choice.
2. Add the following basic CA configuration information:
[ ca ]
default_ca = CA_default
[ CA_default ]
dir = /testCA
certificate = $dir/cacert.pem
database = $dir/index.txt
new_certs_dir = $dir/certs
private_key = $dir/private/caprivkey.pem
serial = $dir/serial
default_crl_days = 7
default_days = 365
default_md = md5
policy = CA_default_policy