Instant Messaging
Instant messaging is the exchange of text messages between users in real time.
The text messages need not to be short and, as we will show, actually quite large
files can be transmitted using suitably designed IM applications. Instant mes-
saging using SIP is based on the MESSAGEmethod [9]. Table 2.5 shows the analo-
gies with SIP voice and video signaling and is also illustrated in Figure 2.1.
Presence and instant communication clients can have a rich graphic user
interface (GUI) for PC displays and also for display phones, palm computers,
mobile phones, and other devices.
It is probable that future communication interfaces will resemble an instant
messaging GUI rather than the present telephone keypad.
The Integration of Communications with Applications
The SIP Event Architecture using messages such as SUBSCRIBEand NOTIFY
is the basis for the integration of communications and applications. A money
transfer can, for example, trigger a communication between the interested par-
ties, or a call with an important customer can trigger, for example, a notifiction
to other employees to join the call or to prepare relevant data for the customer.
E-Commerce: Customer Relations Management
Traditional voice call centers for customer support are migrating to web-based
support centers where the focus is shifting from pure voice (800 numbers) to
e-mail support, text chat, and voice with click-to-connect service. Besides the
shift in functionality, the voice call center part also can be rearchitected from the
ground up. The following aspects are changed from conventional call centers:
■■ The user experience includes web-based choices, IM, and voice, instead
of navigating irritating interactive voice response systems (IVR).
■■ The call center PBX and automatic call distribution systems are replaced
by SIP-based voice and presence-based internal communications.
■■ Customer calls for support can be routed more effectively and at low
cost compared to 800-based PSTN routing.
■■ Call routing inside the contact center can be accomplished by having
the SIP proxy routing database use the following data and criteria:
■■ Caller ID to find the attached data for the customer
■■ The service or product that is supported
■■ The agent with most appropriate skill set
■■ Presence of agentsInternet Communications Enabled by SIP 23