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You may also wish to visit the A-Series IP Phones for Asterisk Overview for additional information and links to related articles.
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OpenVPN is very extensive in terms of the configuration options and therefore is almost impossible for us to test each possible scenario as how you should setup this file is depended on your OpenVPN Server configuration. If you need assistance adding additional paramther parameter please contact your IT Network team as they should provide more information about what parameters are needed in your VPN implementation. if you are implementing a new OpenVPN, you can use the example below, we have confirmed that the following confiration configuration works with Digium A-Phones
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