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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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Each device will also be required to register itself with a Subscription server to enable presence. Within . 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~~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~~rl~C~xxx@sipdomain.tld ' entry in from the default hint in the Admin Web interface into the Subscription URL field.
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