Tag Archives: SIP

Federation stops working after enabling a HostingProvider with “EnabledSharedAddressSpace” turned on

This could be, for example, Lync- or Exchange Online / Office365. Recently, federation broke when implementing “voicemail in the cloud” with Microsoft’s Exchange Online. Microsoft Exchange was configured in Hybrid mode, all successful and operational – users could be moved back and forth and use either Exchange on-premise or Exchange online. Unified Messaging was already enabled

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Show correct Caller ID on blind call transfers to external

As mentioned in one of my previous blog posts, one of the advantages on using an SBC is to be able to connect any “Direct SIP Trunk” to Lync; Microsoft certified or uncertified – as long as its compatible with the SBC’s settings. This time, I had to connect an uncertified SIP Trunk to Lync.

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Issue: One way audio after “call on hold”

Recently, we’ve discovered an issue with “call on hold” functionality in combination with a Cisco CUBE as cpe for Direct SIP-Trunking with Lync 2013. In this situation, we enabled Music on Hold (which is disabled by default), while also respecting all settings and configuration provided by the ITSP for the SIP Trunk. The situation is

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Configure ringing time in Office Communicator 2007 R2

Some of my Enterprise Voice customers complained about the short notice that they had to answer an incoming call. They thought the OC stopped ringing after 3-4 rings, and the call was disconnected. After a short troubleshooting session with wireshark, it was easy to see that OCS terminated the call;

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