Some interesting links on this topic whilst researching for a current customer project for Managed RMX Lync integration and Federation
Polycom RMX Layouts in Lync
Page 30 /is where is starts to get relevant and some techie stuff from pages 35
Taken from the Polycom guide…
Federation is a trust relationship between two or more SIP domains that permits users in separate organizations to communicate in real-time across network boundaries as federated partners.
Federated users are users from another enterprise (registered to a different Office Communications Server on a different network) that are able to make and receive calls to endpoints and video infrastructure
…I companyB wants to connect to calls managed by a DMA system or RMX system on companyA, companyB must add the companyA domains to its list of allowed SIP domains in the Office Communications Server edge server.
Likewise if companyA wants to connect to calls managed by a DMA system or RMX system on companyB, companyB’s SIP domains must be on the allowed SIP domain list of companyA’s edge server…
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