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For every user the admin can pre-configure a list of speed dial keys. Selecting the check box next to the entry enables BLF presence functionality. sipXecs uses a centralized phone presence server (called Resource List Server) to offer presence information for the entire systemto phones that support RLS. This approach is much more scalable and versatile vis-a-vis a peer-to-peer approach where every phone would subscribe for presence directly with the other phone. Tests have shown that the peer-to-peer approach causes significant network traffic that can cause a LAN to break down with only several hundred phones connected. The centralized approach implemented by sipXecs, in contrary, scales very well.

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Every use can use his / her user configuration portal to configure speed dial and BLF presence functionality. The user can easily make changes at any time. The sipXecs system automatically updates the phone's configuration profile with the new speed dial and BLF information. The phone is then remotely restarted automatically to pick-up the new configuration information.

Configuring Device BLF settings

Each device will also be required to register itself with a Subscription server to enable presence. By default, this section should already be populated. To review settings within the Admin Web interface, edit the device's BLF properties.

For the Subscription URL field, a default value should be displayed next to the field. That value should be (Default: sip:~~rl~C~xxx@sipdomain.tld), where xxx is replaced with your extension, and sipdomain.tld is replaced with your SIP domain. Copy and paste the ~~rl~C~xxx@sipdomain.tld entry from the default hint in the Admin Web interface into the Subscription URL field.

The Subscription Server dropdown value should be 'Primary Registration Server' unless you have needs to insert a different value.

For Polycom phones, after changing this value you will need to Send the Profile and Restart the phone.