Part 1
The Case for SIP
In This Part
ᮣ Defining SIP
ᮣ Connecting people anywhere, anytime, on any device
ᮣ Facilitating interoperability
ᮣ Streamlining communications with or without servers
ᮣ Preparing for the future of SIP
D
o you increasingly feel like your communication devices
are holding you hostage? Just as you finish checking
your multiple voice mailboxes you get an instant message
from someone that you just left a message for, saying, “I’m off
the phone now, can you call me back?” Or have you left a
greeting on your work voice mail saying, “If you’ve missed
me, you can call me on my cell phone, or better yet, send me
an e-mail if this is after hours.” You may be rapidly reaching
the conclusion that everyone has too many devices, too
many numbers, and too little time. Sometimes modern com-
munications technology seems to have forgotten the main
reason for using it: to communicate with another person
more conveniently.
People have more options available to them today for com-
municating with each other than ever, yet they often have a
harder time getting through. The selection of choices spans
a dizzying array of technologies and devices that can deliver
voice, e-mail, instant messages, and even video. Simply picking
up the phone still works, but now users have more choices
for deciding how to reach somebody — and, ironically, that is
the problem.
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