1. 1 SIP-based VoIP Lab

2. 2 Step 1: Connect Your PC to The Network Get your laptop connected to the campus WLAN. –Run ipconfig to show your own IP address –Ping SIP.ipv6.club.tw (10.20.20.17) –Ping voipgw.ncnu.edu.tw (163.22.9.227)

3. 3 IP Addresses We Obtained 11 – 10.10.19.165 12 – 10.10.19.188 13 - 10.10.19.71 14 – 10.10.19.170 15 – 10.10.19.121 10 – 10.10.19.4 –Auto-Answer 16 – 10.10.19.47 17 – 10.10.19.199 18 – 10.10.19.164 19 – 10.10.19.94 20 – 10.10.19.85

4. 4 Step 2: Install Wireshark under Windows Install Wireshark 1.12.2. –It will automatically install WinPcap. Install WinPcap 4.1. –WinPcap is an architecture for packet capture and network analysis for the Win32 platforms. –It includes a kernel-level packet filter, a low-level dynamic link library (packet.dll), and a high-level and system-independent library (wpcap.dll, based on libpcap version 1.1.1)libpcap

5. 5 Where to Get Wireshark Official site: –http://www.wireshark.org/download.htmlhttp://www.wireshark.org/download.html

6. 6 Step 3: Install a SIP UA Windows Messenger 4.7 (4.7.2009) –Windows XP SP2 will remove the SIP support in Messengers Windows Messenger 5.1 CounterPath X-LiteX-Lite Linphone 3.7 for WindowsLinphone TECOM WiFi phone

7. 7 X-Lite INVITE/200 OK/ACK BYE/200 OK Hold/Retrieve RTP

8. 8 Step 4: REGISTER Configure the proxy server to be –sip.ipv6.club.tw (10.20.20.17) Start your Wireshark –Disable promiscuous mode –Capture Filter: udp port 5060 –Display the captured packets in real-time –OK Start X-Lite Sign-in and observe the packets you capture

9. HTTP-Digest on SIP 9

10. 10 Ex 1: –Everybody sign-in and sign-off to see the SIP messages. –Sign-in Expires: 3600 –Sign-off Expires: 0 Ex 2: –Two UAs sign in with the same username. 2 Bindings –One UA signs off 1 Binding –The other UA signs off 0 Bindings

11. 11 Now everybody restores to your original username. Keep Wireshark running.

12. 12 Test Your Microphone & Speaker

13. 13 Call Scenarios Practice using this tool to capture SIP signaling in the following call flows –REGISTER – 200 OK –INVITE – 200 OK – ACK –INVITE – CANCEL – 200 OK - ??? – ACK –INVITE – Decline (???) - ACK –BYE – 200 OK –Hold/Retrieve

14. 14 INVITE Pairing students into groups Let the student with lower username be the caller, and the other student be the callee. Make the call. Exchange the role, and make the call again. 1.Call instructor’s X-Lite –10@SIP.ipv6.club.tw 2.Call NCNU PBX –4161 (COM), 4131 (CSIE) –4161@voipgw.ncnu.edu.tw Compare the signaling flow of the above two cases

15. 15 Via On The receiver side, observe the Via header field of a request, and compare it with the Via header field which was generated by the sender. Also observe the difference of the Max- Forwards header field.

16. 16 SIP Forking B and C register with the same username. Ex 1: –A calls B, C. –B answers. –C receives a CANCEL request. Ex 2: –A calls B, C –Nobody answers. –A hangs up.

17. 17 Contact List Presence –SUBSCRIBE/NOTIFY –RFC 3265 Instant Message –MESSAGE –RFC 3428

18. SDP 18

19. 19 Next: Try to capture RTP packets Open a new Wireshark –The old one is still running to capture SIP signaling. Capturing Filter: udp You will obtain 50 packets in a second –Analyze – Decode As – RTP Can you choose a different codec?