Chapter 46 Certificates
ZyWALL USG 300 User’s Guide
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2
Tim keeps the private key and makes the public key openly available. This means
that anyone who receives a message seeming to come from Tim can read it and
verify whether it is really from him or not.
3
Tim uses his private key to sign the message and sends it to Jenny.
4
Jenny receives the message and uses Tim’s public key to verify it. Jenny knows
that the message is from Tim, and that although other people may have been able
to read the message, no-one can have altered it (because they cannot re-sign the
message with Tim’s private key).
5
Additionally, Jenny uses her own private key to sign a message and Tim uses
Jenny’s public key to verify the message.
The ZyWALL uses certificates based on public-key cryptology to authenticate users
attempting to establish a connection, not to encrypt the data that you send after
establishing a connection. The method used to secure the data that you send
through an established connection depends on the type of connection. For
example, a VPN tunnel might use the triple DES encryption algorithm.
The certification authority uses its private key to sign certificates. Anyone can then
use the certification authority’s public key to verify the certificates.
A certification path is the hierarchy of certification authority certificates that
validate a certificate. The ZyWALL does not trust a certificate if any certificate on
its path has expired or been revoked.
Certification authorities maintain directory servers with databases of valid and
revoked certificates. A directory of certificates that have been revoked before the
scheduled expiration is called a CRL (Certificate Revocation List). The ZyWALL can
check a peer’s certificate against a directory server’s list of revoked certificates.
The framework of servers, software, procedures and policies that handles keys is
called PKI (public-key infrastructure).
Advantages of Certificates
Certificates offer the following benefits.
• The ZyWALL only has to store the certificates of the certification authorities that
you decide to trust, no matter how many devices you need to authenticate.
• Key distribution is simple and very secure since you can freely distribute public
keys and you never need to transmit private keys.
Self-signed Certificates
You can have the ZyWALL act as a certification authority and sign its own
certificates.
Summary of Contents for Unified Security Gateway ZyWALL 300
Page 2: ......
Page 30: ...Table of Contents ZyWALL USG 300 User s Guide 30 ...
Page 31: ...31 PART I User s Guide ...
Page 32: ...32 ...
Page 38: ...Chapter 1 Introducing the ZyWALL ZyWALL USG 300 User s Guide 38 ...
Page 46: ...Chapter 2 Features and Applications ZyWALL USG 300 User s Guide 46 ...
Page 64: ...Chapter 3 Web Configurator ZyWALL USG 300 User s Guide 64 ...
Page 74: ...Chapter 4 Installation Setup Wizard ZyWALL USG 300 User s Guide 74 ...
Page 116: ...Chapter 6 Configuration Basics ZyWALL USG 300 User s Guide 116 ...
Page 184: ...Chapter 7 Tutorials ZyWALL USG 300 User s Guide 184 ...
Page 221: ...221 PART II Technical Reference ...
Page 222: ...222 ...
Page 288: ...Chapter 11 Registration ZyWALL USG 300 User s Guide 288 ...
Page 378: ...Chapter 14 Trunks ZyWALL USG 300 User s Guide 378 ...
Page 394: ...Chapter 15 Policy and Static Routes ZyWALL USG 300 User s Guide 394 ...
Page 408: ...Chapter 16 Routing Protocols ZyWALL USG 300 User s Guide 408 ...
Page 428: ...Chapter 19 NAT ZyWALL USG 300 User s Guide 428 ...
Page 454: ...Chapter 23 Authentication Policy ZyWALL USG 300 User s Guide 454 ...
Page 472: ...Chapter 24 Firewall ZyWALL USG 300 User s Guide 472 ...
Page 534: ...Chapter 27 SSL User Screens ZyWALL USG 300 User s Guide 534 ...
Page 536: ...Chapter 28 SSL User Application Screens ZyWALL USG 300 User s Guide 536 ...
Page 544: ...Chapter 29 SSL User File Sharing ZyWALL USG 300 User s Guide 544 ...
Page 638: ...Chapter 35 ADP ZyWALL USG 300 User s Guide 638 Figure 448 Profiles Protocol Anomaly ...
Page 682: ...Chapter 37 Content Filter Reports ZyWALL USG 300 User s Guide 682 ...
Page 700: ...Chapter 38 Anti Spam ZyWALL USG 300 User s Guide 700 ...
Page 722: ...Chapter 39 Device HA ZyWALL USG 300 User s Guide 722 ...
Page 738: ...Chapter 40 User Group ZyWALL USG 300 User s Guide 738 ...
Page 744: ...Chapter 41 Addresses ZyWALL USG 300 User s Guide 744 ...
Page 756: ...Chapter 43 Schedules ZyWALL USG 300 User s Guide 756 ...
Page 772: ...Chapter 45 Authentication Method ZyWALL USG 300 User s Guide 772 ...
Page 794: ...Chapter 46 Certificates ZyWALL USG 300 User s Guide 794 ...
Page 806: ...Chapter 48 SSL Application ZyWALL USG 300 User s Guide 806 ...
Page 811: ...Chapter 49 Endpoint Security ZyWALL USG 300 User s Guide 811 ...
Page 866: ...Chapter 50 System ZyWALL USG 300 User s Guide 866 ...
Page 873: ...Chapter 51 Log and Report ZyWALL USG 300 User s Guide 873 ...
Page 886: ...Chapter 51 Log and Report ZyWALL USG 300 User s Guide 886 ...
Page 916: ...Chapter 54 Packet Flow Explore ZyWALL USG 300 User s Guide 916 ...
Page 918: ...Chapter 55 Reboot ZyWALL USG 300 User s Guide 918 ...
Page 920: ...Chapter 56 Shutdown ZyWALL USG 300 User s Guide 920 ...
Page 948: ...Chapter 58 Product Specifications ZyWALL USG 300 User s Guide 948 ...
Page 1014: ...Appendix A Log Descriptions ZyWALL USG 300 User s Guide 1014 ...
Page 1124: ...Appendix F Open Software Announcements ZyWALL USG 300 User s Guide 1124 ...