Here are the configuration steps for a typical way to use the AudioCodes Stand-Alone Survivability (SAS) Feature with AudioCodes 65.0 firmware (available in sipXecs 4.2)80a firmware and later.

Introduction

The SAS feature can be useful for a branch office that has a local AudioCodes Gateway, but uses a remote sipXecs server. In "Normal" mode the AudioCodes Gateway transparently proxies the SIP messages between the phones and sipXecs server. It also sends periodic "keepalive" messages to the sipXecs server in order to confirm connectivity. If connectivity to the sipXecs server is lost then the AudioCodes Gateway goes into "Failover" mode allowing branch phones to make calls out the PSTN and to each other. Once connectivity is restored, the AudioCodes Gateway switches back to "Normal" mode.

The instructions below are based on the results of my testing with an AudioCodes Mediant 1000 PRI (6.00 firmware), an Avaya 1230, and an LG-Nortel 6810.

Configuration Steps

sipXconfig Phone Profiles

To have a phone use SAS, configure its Outbound Proxy values as follows:

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The profile of course also needs to be re-generated and sent to the phone.

sipXconfig Dial Plan

The Dial Plan must be constructed so that all digits dialed by the user are passed to the AudioCodes Gateway. i.e. None of your PSTN rules can have prefixes that are dropped before the call is sent to the gateway.

This means you cannot use the built-in "Local" or "Long Distance" rules, and you will need to construct "Custom" rules instead. The "Emergency" rule may be used, although you should test that it works in both Normal and Emergency mode.

sipXconfig AudioCodes Gateway Profile

Only three changes need to be made to the AudioCodes Gateway Profile to enable SAS:

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