ߜ Interoperability among IVRs.
ߜ Firewalls.
ߜ Conferencing bridges.
ߜ Instant messaging platforms.
In essence, these systems must rely on much more than stan-
dard SIP to make them work together.
Nevertheless, SIP offers new options for multi-vendor inte-
gration within an IP telephony environment based on open
standards. First, when needed, a specific user agent (a client
device such as a PDA phone) can be connected to the PBX
through SIP. Next, through federation services, you can support
basic connectivity between different vendors’ PBX systems
using SIP. Soon, SIP will enable enterprises to combine multi-
ple PBXs into a single system, which reduces complexity for
both users and administrators.
Part 5: SIP Interoperability
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