In a converged network, voice becomes an IP application,
sharing the common network infrastructure and services.
Connecting SIP Enterprises
A common concern for companies contemplating the switch
to SIP is how quickly all these nifty advances are going to
come together in a truly comprehensive way. In particular:
how can isolated enterprises exchange directory information?
Sure, each step toward SIP is a step in the right direction,
but how do you get everyone marching in step? The SIP
world calls reaching that higher level of inter-connectedness
federating.
In recent years, businesses have enthusiatically adopted IP
for their intracompany communications. For example, today
more IP PBXs are sold than conventional TDM PBXs.
However, today, most of these IP communications tools stop
at the enterprise boundary. IP PBXs “fall back” to TDM and
revert to phone calls for communication outside of the enter-
prise. As a result, “islands” of IP communication are growing,
but they are not interconnected. As SIP has matured as a
standard, the interconnection of these islands over the
Internet has become a technical possibility.
The benefits of such interconnection are enormous. For
instance, you can
ߜ Extend enhanced services beyond the enterprise
boundary.
ߜ Make available additional modes of communication
including multimedia, presence, and IM.
ߜ Enjoy higher-quality connections.
ߜ Reduce costs by bypassing TDM network
interconnections.
If two enterprises both have SIP, they can interconnect and
enable SIP-to-SIP calling. Beyond calling, they can now interact
via multimedia sessions, presence, and instant messaging.
What are the obstacles to this interconnection? To enjoy the
full benefits of SIP, you need to overcome three main barriers:
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