Cisco ONS 15400 Series

A. The answer to this depends on the software version used on the ONS 15454 or ONS 15327 equipment.

For ONS 15454 or ONS 15327 Software Release 3.3.x and Later

The answer is yes. ONS 15454 (and ONS 15327) Software Release 3.3 introduces functionality to allow Cisco Transport Controller sessions over NAT connections.

Note: The NAT feature is only supported when the Network Proxy Server option is enabled. Choose CTC Node View > Provisioning > Network > Enable Proxy in order to enable the Network Proxy Server.

For ONS 15454 or ONS 15327 Software Release Earlier Than 3.3 (Including 2.x.x, 3.1.x, and 3.2.x)

The answer is no. NAT causes an issue in which the terminating call control (TCC) attempts a callback through Common Object Request Broker (ORB) Architecture (CORBA). Since the inter-ORB references (the remote reference of objects) depend upon the IP address of the client, this fails and causes a connection loss approximately every 30 seconds. It causes nodes to appear and disappear in network view.

Detailed information about this scenario:

Symptom—If you run Cisco Transport Controller across a NAT, Cisco Transport Controller comes up but detects a connection loss and returns you to the network view. It continues to do so approximately every 30 seconds.

Conditions—This occurs whenever address translation occurs between the Cisco Transport Controller and TCC.

Exists in Field (yes/no)—Yes, if NAT occurs in the network firewall.

Workaround—A currently successful workaround involves the use of a terminal server with an appropriate version of Netscape or Microsoft Internet Explorer installed. The terminal server must be on the same side of the firewall (trusted or untrusted) as the ONS 15454 or ONS 15327. For this document, a Microsoft Windows 2000 server and Windows Terminal Services client are used.