Part III: How SIP Transforms User Communications
describes how SIP “addressing” works with the concept of
presence to make reaching users easier, regardless of which
device they’re using or where they are.
Part IV: How SIP Transforms Enterprise Communications
explains how SIP drives down the cost and complexity of
intra-enterprise and inter-enterprise communications by
permitting their consolidation with IP data communications.
This part delves into the details of basic SIP calls, including
proxy-mediated voice calls, presence-enabled calls, instant
messaging, and videoconferencing. Here we explain the con-
cept of trunking — that is, connecting enterprises’ IP-based
communications systems together over long distances. We
also discuss ENUM, the protocol that bridges the new SIP-
based URI system with the old TDM phone number system.
Part V: SIP Interoperability discusses the principles needed
to support an enterprise migration to SIP. No two enterprises
are alike, so it would be difficult to come up with a single
works-for-all recipe for migrating to SIP. Instead, this part
explains what vendors are doing to make multi-vendor inte-
gration with SIP as straightforward as possible.
Part VI: SIP and Server-Free Communications discusses
how small businesses and distributed offices can take advan-
tage of SIP features, even without dedicated servers.
Part VII: SIP and the Future of Intelligent Communications
looks into the future of SIP and how it will continue to evolve
and improve, embracing more communication technologies
and supporting more enhanced communications capabilities.
Part VIII: Top Ten Reasons for SIP-Enhanced
Communications offers a condensed list of the most impor-
tant reasons to put your communications on steroids. SIP will
make your communications more intelligent than anything
else available today. This intelligence pays off in more effec-
tive communications that result in happier customers and
more productive employees. If you’re still sitting on the fence
about SIP, start here.
Introduction
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