SIP Silent Rejection Service
The second in a series of mini tutorials presented by...
SIPKnowledge, Inc. 
Motivation:
It is 10pm. Alice is just about getting ready to sleep. It has been two weeks now, since her breakup from Barry. He has been stalking and bothering her since then. Following her to work, calling her to the office all the time and worst of all, interrupting her nights sleep by repetitive annoying calls followed by immediate hang-ups...
The office and car stalking she can take... but the late night phone calls. This is way too much! In theory she can turn off the ringers of her 5 new cool SIP phones (Kitchen, Living room, bed room, wireless and soft phone on the PC), but then what if there is an important incoming call? What if her sick father needs urgent help? Ugh...!
If there was just some magical button that she could push and made ALL of her phones automatically and silently reject Barry’s calls (e.g. Provide him a busy indication without ringing) while enabling other incoming calls!
Feature:
Activation time
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Any of Alice's SIP phones will enable her via user friendly interface to block incoming calls from certain users (by using either the users names, telephone numbers or any other Identifier). Once the blocking request is input by Alice, the SIP phone silently contacts all other SIP phones of Alice (same SIP/TEL URI) and instruct them to block incoming calls from the particular users.
Calling time
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Incoming calls From Barry are returned silent busy indication from Alice’s SIP phone(s).
How this can be accomplished:
The following scheme illustrates how this can be accomplished.
SIPKnowledge, Inc. 
SIPKnowledge pursue research combined with actual product (and standard) work and provide its outcome in a shape of self paced eLearning courses, seminars (on-site training) and actual products. The courses and seminars offer information/self-training on SIP, IP telephony (VoIP) and 3G IMS. Products include:
- Consulting
- SIP/IMS training courses
1. SIP Illustrated - SIP eLearning course
2. 3G IMS Illustrated - 3G IMS eLearning course
- SIP developers aid tools
1. SIP RFC (3261) navigator and clarifier tool
http://www.sipcenter.com/goto/sipcenter-sipknowledge
SIPKnowledge Mini Tutorials Series
4. Remote Monitoring via SIP
3. SIP Call Redirection
2. SIP Silent Rejection Service
1. Personal/Selective Presence with SIP Presence and XML directives