About security certificates
For extra security, you may want to have the VCS communicate with other systems (such as LDAP servers,
neighbor VCSs, or clients such as SIP endpoints and web browsers) using TLS encryption.
For this to work successfully in a connection between a client and server:
n
The server must have a certificate installed that verifies its identity. This certificate must be signed by a
Certificate Authority (CA).
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The client must trust the CA that signed the certificate used by the server.
The VCS allows you to install appropriate files so that it can act as either a client or a server in connections
using TLS. The VCS can also authenticate client connections (typically from a web browser) over HTTPS.
You can also upload certificate revocation lists (CRLs) for the CAs used to verify LDAP server and HTTPS
client certificates.
The VCS can generate server certificate signing requests (CSRs). This removes the need to use an external
mechanism to generate and obtain certificate requests.
For secure communications (HTTPS and SIP/TLS) we recommend that you replace the VCS default
certificate with a certificate generated by a trusted certificate authority.
Note that in connections:
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to an endpoint, the VCS acts as the TLS server
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to an LDAP server , the VCS is a client
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between two VCS systems, either VCS may be the client with the other VCS being the TLS server
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via HTTPS, the web browser is the client and the VCS is the server
TLS can be difficult to configure. For example, when using it with an LDAP server we recommend that you
confirm that your system is working correctly before you attempt to secure the connection with TLS. You are
also recommended to use a third party LDAP browser to verify that your LDAP server is correctly configured
to use TLS.
Note:
be careful not to allow your CA certificates or CRLs to expire as this may cause certificates signed by
those CAs to be rejected.
Certificate and CRL files can only be managed via the web interface. They cannot be installed using the CLI.
See
Managing the trusted CA certificate list [p.285]
and
Managing the VCS's server certificate [p.286]
for
instructions about how to install certificates. For further information, see
Certificate Creation and Use with
VCS Deployment Guide
.
Managing the trusted CA certificate list
The
Trusted CA certificate
page (
Maintenance > Security certificates > Trusted CA certificate
) allows
you to manage the list of certificates for the Certificate Authorities (CAs) trusted by this VCS. Certificates
presented to the VCS must be signed by a trusted CA on this list and there must be a full chain of trust
(intermediate CAs) to the root CA.
n
To upload a new file of CA certificates,
Browse
to the required PEM file and click
Append CA
certificate
. This will append any new certificates to the existing list of CA certificates. Note that if you are
replacing existing certificates for a particular issuer and subject, you have to manually delete the previous
Cisco VCS Administrator Guide (X8.1.1)
Page 285 of 507
Maintenance
About security certificates