Cisco Systems Edit TLS Proxy Instance Server Configuration

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Cisco ASA 5500 Series Configuration Guide using ASDM
Chapter53 Configuring the TLS Proxy for Encrypted Voice Inspection
CTL Provider
Edit TLS Proxy Instance – Server Configuration
Note This feature is not supported for the Adaptive Security Appliance version 8.1.2.
The TLS Proxy enables inspection of SSL encrypted VoIP signaling, namely Skinny and SIP, interacting
with Cisco Call Manager and to support the Cisco Unified Communications features on the ASA.
Use the Edit TLS Proxy – Server Configuration tab to edit the server proxy parameters for the original
TLS Server—the Cisco Unified Call Manager (CUCM) server, the Cisco Unified Presence Server
(CUPS), or the Cisco Unified Mobility Advantage (CUMA) server.
Step1 Open the Configuration > Firewall > Unified Communications > TLS Proxy pane.
Step2 To edit a TLS Proxy Instance, click Edit.
The Edit TLS Proxy Instance dialog box opens.
Step3 If necessary, click the Server Configuration tab.
Step4 Specify the server proxy certificate by doing one of the following:
•To add a new certificate, click Manage. The Manage Identify Certificates dialog box opens.
When the Phone Proxy is operating in a mixed-mode CUCM cluster, you must import the CUCM
certificate by clicking Add in the Manage Identify Certificates dialog box. See the “Configuring CA
Certificate Authentication” section on page 44-10.
•To select an existing certificate, select one from the drop-down list.
When you are configuring the TLS Proxy for the Phone Proxy, select the certificate that has a
filename beginning with _internal_PP_. When you create the CTL file for the Phone Proxy, the
ASA, creates an internal trustpoint used by the Phone Proxy to sign the TFTP files. The trustpoint
is named _internal_PP_ctl-instance_filename.
The server proxy certificate is used to specify the trustpoint to present during the TLS handshake. The
trustpoint can be self-signed or enrolled locally with the certificate service on the proxy. For example,
for the Phone Proxy, the server proxy certificate is used by the Phone Proxy during the handshake with
the IP phones.
Step5 To install the TLS server certificate in the ASA trust store, so that the ASA can authenticate the TLS
server during TLS handshake between the proxy and the TLS server, click Install TLS Server’s
Certificate.
The Manage CA Certificates dialog box opens. See the “Guidelines and Limitations” section on
page 44-9. Click Add to open the Install Certificate dialog box. See the “Configuring CA Certificate
Authentication” section on page44-10.
When you are configuring the TLS Proxy for the Phone Proxy, click Install TLS Server’s Certificate
and install the Cisco Unified Call Manager (CUCM) certificate so that the proxy can authenticate the IP
phones on behalf of the CUCM server.
Step6 To require the ASA to present a certificate and authenticate the TLS client during TLS handshake, check
the Enable client authentication during TLS Proxy handshake check box.
When adding a TLS Proxy Instance for Mobile Advantage (the CUMC client and CUMA server), disable
the check box when the client is incapable of sending a client certificate.
Step7 Click Apply to save the changes.