HP 250m Print Server - Fast Ethernet, 250m Print Server for Fast Ethernet Asymmetric Cryptography

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Figure 16 - Asymmetric Cryptography

Here we can see the difference between asymmetric and symmetric cryptography. One key can be used for encryption and then the corresponding key can be used for decryption. It appears that asymmetric cryptography has solved the key distribution issue; however there are two new attributes usually associated with asymmetric cryptography

It is slow

It has a trust problem. How do I know that this is John’s public key and not someone pretending to be John?

To solve the first problem, asymmetric cryptography is usually used to securely distribute symmetric keys and sign hash codes. In short, what is actually being encrypted and decrypted is usually much smaller than actual messages. This has the nice benefit of solving the key distribution issue with symmetrical cryptography. So, in essence, symmetric keys are sent securely using asymmetric cryptography and the actual messages themselves are protected using symmetric cryptography. Cool! We get the flexibility of asymmetric cryptography and the speed of symmetric cryptography. Now we only have to solve the trust problem.

In order to solve the trust problem, five things will need to be discussed:

A certificate authority – a trusted third party that creates digital certificates from certificate requests

A certificate request – a public key associated with identity information that will serve as the basic building block for a digital certificate that the certificate authority will create and sign.

A digital certificate – a public key associated with identity information that is digitally signed by the certificate authority.

A digital signature – the hash of the digital certificate encrypted by the private key of the certificate authority.

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Contents Whitepaper IntroductionWhat is SSL/TLS? Http ApplicationHttps Decoded Application ChangesHttp Session More Info Https Session Lock Icon Certificate Details Digital Certificates IE6 Security AlertIE7 Certificate Error IE7 Certificate Error Public Key Infrastructure and Public Key Certificate Basics Certificate InformationSymmetric Cryptography Asymmetric Cryptography Digital Signature Digital Signature Verification Certificate Authority Public Key Certificates Self-Signed Certificate SSL/TLS Protocol Basics SSL/TLS Protocol StructuresClient Hello Server Hello Server Certificate Verification Keying Material Client Finished Using Https with HP Jetdirect Server FinishedCA Heirarchy Network Diagram Page Page Under the heading Jetdirect Certificate, press Configure… Page Page Page Page Page Page Page Page Page Page Page Save it Go to Tools and click Internet Options Click Certificates Click Import… Click Next Select the file Click Next Page Page Page Page Page Detailed Look at the SSL/TLS Connection Page Page Page Page Check for server certificate revocation is not selected Page Page SSL/TLS Server Settings HP Jetdirect as an SSL/TLS Client Page Page Page Page Select R2 and hit Export… Click Next Select DER. Click Next Save it Save it Click Finish Page Select the file. Click Finish Click OK Page Same message. What did we do wrong? Page Page We use the DNS name and try again Success Page SSL/TLS Client Understanding Certificate Chains CA HierarchyPage RootCA Incorrect HP Jetdirect CA Configuration Correct HP Jetdirect CA Configuration Walking the Chain SSL/TLS Client Certificates and Name Verification Subject SubjectAltName Page Page Page IPP over SSL/TLS Click Next Select a network printer… Page Page Print a test Yep we have our print data protected by SSL/TLS HP Jetdirect Certificate Guidelines Embedded Devices and Digital CertificatesWhich HP Jetdirect Products Support SSL/TLS? Summary