HP 635n - JetDirect IPv6/IPsec Print Server How To Use Manual page 14

Figure 15 – Public Key Certificates
Here we can see that everyone's public key certificate is, well – um, public. The important thing to
note is that the certificate authority also has a public key certificate that identifies itself. This certificate
is signed with its own private key and is a "self-signed" certificate. There is no "higher" level of trust
then the top level certificate authority. Therefore, John and Jack must choose a particular certificate
authority that they both trust. In most cases, there is a hierarchy of certificate authorities at customer
sites. This forms what is known as a certificate chain and there is a top level CA or Root CA where
the ultimate trust resides.
Also, we should take care to point out that there is usually a difference between Internet trust using
certificates and Intranet trust using certificates. Internet trust will involve well-known certificate
authorities like Verisign and Entrust. However, Intranet models usually revolve around Microsoft's
certificate authority that comes with Windows 2003 server. Each company establishes their own
Public Key Infrastructure (PKI) that includes an entire policy around certificates.
Now that we have covered some basics around certificates, we can talk specifically about Jetdirect.
Jetdirect is an embedded system and as a result, has limited storage space for certificates. Jetdirect
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