Polycom IP 320 Administrator's Manual page 158

Administrator's Guide for the SoundPoint IP / SoundStation IP / VVX Family
4 - 96
An X.509 digital certificate is a digitally signed statement. The X.509 standard
defines what information can go into a certificate. All X.509 certificates have
the following fields, in addition to the signature:
• Version. This identifies which version of the X.509 standard applies to this
certificate, which affects what information can be specified in it.
• Serial Number. The entity that created the certificate is responsible for
assigning it a serial number to distinguish it from other certificates it
issues.
• Signature Algorithm Identifier. This identifies the algorithm used by the
Certificate Authority (CA) to sign the certificate.
• Issuer Name. The X.500 name of the entity that signed the certificate. This
is normally a CA. Using this certificate implies trusting the entity that
signed this certificate.
• Validity Period. Each certificate is valid only for a limited amount of time.
This period is described by a start date and time and an end date and time,
and can be as short as a few seconds or almost as long as a century.
• Subject Name. The name of the entity whose public key the certificate
identifies. This name uses the X.500 standard, so it is intended to be unique
across the Internet.
• Subject Public Key Information. This is the public key of the entity being
named, together with an algorithm identifier which specifies which public
key cryptographic system this key belongs to and any associated key
parameters.
The following is an example of a Polycom device certificate (if opened with the
Microsoft Internet Explorer 7 or Firefox 3.5 browser on a computer running
Microsoft XP Service Pack 3):
The device certificate and associated private key are stored on the phone in its
non-volatile memory as part of the manufacturing process.