title: SipVicious(100) incoming calls in my Sip Application
body: <p>I build my Android Sip application using pjsua library. I am using BSNL Wings service provider for sip account. I am receiving a call from 100, randomly at my phone which have no response from the other side even when answered.</p>
  
  <p>I took the log, and came to know that these are sipvicious calls. How can I block such suspicious calls? Is this because of my apps poor security?</p>
  
  <p>Below is some piece of logs</p>
  
  <pre><code>10:56:45.807   pjsua_core.c  .RX 406 bytes Request msg INVITE/cseq=1 (rdata0x94078014) from UDP 185.53.88.90:5104:
  INVITE sip:100@25.66.144.5:5060 SIP/2.0
  Via: SIP/2.0/UDP 127.0.0.1:5104;branch=z9hG4bK-935159066;rport
  Content-Length: 0
  From: "sipvicious"&lt;sip:100@1.1.1.1&gt;;tag=3839363132643836313363340131333034323431323430
  Accept: application/sdp
  User-Agent: friendly-scanner
  To: "sipvicious"&lt;sip:100@1.1.1.1&gt;
  Contact: sip:100@127.0.0.1:5104
  CSeq: 1 INVITE
  Call-ID: 470941564413303467070167
  Max-Forwards: 70
  --end msg--
  SIP/2.0 100 Trying
  Via: SIP/2.0/UDP 127.0.0.1:5104;rport=5104;received=185.53.88.90;branch=z9hG4bK-935159066
  Call-ID: 470941564413303467070167
  From: "sipvicious" &lt;sip:100@1.1.1.1&gt;;tag=3839363132643836313363340131333034323431323430
  To: "sipvicious" &lt;sip:100@1.1.1.1&gt;
  CSeq: 1 INVITE
  Content-Length:  0
  --end msg--
  ======== Incoming call ======== 
  handleMessage: INCOMING_CALL
  10:56:45.830   pjsua_call.c !Answering call 0: code=180
  10:56:45.830   pjsua_core.c  ....TX 499 bytes Response msg 180/INVITE/cseq=1 (tdta0x93618064) to UDP 185.53.88.90:5104:
  SIP/2.0 180 Ringing
  Via: SIP/2.0/UDP 127.0.0.1:5104;rport=5104;received=185.53.88.90;branch=z9hG4bK-935159066
  Call-ID: 470941564413303467070167
  From: "sipvicious" &lt;sip:100@1.1.1.1&gt;;tag=3839363132643836313363340131333034323431323430
  To: "sipvicious" &lt;sip:100@1.1.1.1&gt;;tag=af653679-5911-4a3d-bbe6-a83c8d50b2d2
  CSeq: 1 INVITE
  Contact: &lt;sip:+919188991609@25.66.144.5:5060;ob&gt;
  Allow: PRACK, INVITE, ACK, BYE, CANCEL, UPDATE, INFO, SUBSCRIBE, NOTIFY, REFER, MESSAGE, OPTIONS
  ....
  ....
  ....
  SIP/2.0 200 OK
  Via: SIP/2.0/UDP 127.0.0.1:5104;rport=5104;received=185.53.88.90;branch=z9hG4bK-935159066
  Call-ID: 470941564413303467070167
  To: "sipvicious" &lt;sip:100@1.1.1.1&gt;;tag=af653679-5911-4a3d-bbe6-a83c8d50b2d2
  CSeq: 1 INVITE
  Allow: PRACK, INVITE, ACK, BYE, CANCEL, UPDATE, INFO, SUBSCRIBE, NOTIFY, REFER, MESSAGE, OPTIONS
  Contact: &lt;sip:+919188991609@25.66.144.5:5060;ob&gt;
  Supported: replaces, 100rel, timer, norefersub
  Content-Type: application/sdp
  Content-Length:   512
  v=0
  o=- 3779674023 3779674023 IN IP4 25.66.144.5
  s=pjmedia
  b=AS:84
  t=0 0
  a=X-nat:0
  m=audio 4000 RTP/AVP 98 97 99 104 3 0 8 9 96
  c=IN IP4 25.66.144.5
  b=TIAS:64000
  a=rtcp:4001 IN IP4 25.66.144.5
  a=sendrecv
  a=rtpmap:98 speex/16000
  a=rtpmap:97 speex/8000
  a=rtpmap:99 speex/32000
  a=rtpmap:104 iLBC/8000
  a=fmtp:104 mode=30
  a=rtpmap:3 GSM/8000
  a=rtpmap:0 PCMU/8000
  a=rtpmap:8 PCMA/8000
  a=rtpmap:9 G722/8000
  a=rtpmap:96 telephone-event/8000
  a=fmtp:96 0-16
  a=ssrc:1119297598 cname:6bbc3fa2607711b7
  --end msg--
  BYE sip:100@127.0.0.1:5104 SIP/2.0
  Via: SIP/2.0/UDP 25.66.144.5:5060;rport;branch=z9hG4bKPj149e8a65-dad5-4d32-a539-6b68b23a1e8f
  Max-Forwards: 70
  From: "sipvicious" &lt;sip:100@1.1.1.1&gt;;tag=af653679-5911-4a3d-bbe6-a83c8d50b2d2
  To: "sipvicious" &lt;sip:100@1.1.1.1&gt;;tag=3839363132643836313363340131333034323431323430
  Call-ID: 470941564413303467070167
  CSeq: 30149 BYE
  Content-Length:  0
  --end msg--
  </code></pre>