tailieunhanh - VoIP Technologies Part 8

Tham khảo tài liệu 'voip technologies part 8', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 166 VoIP Technologies Message ACK SIP 1000@ 5060 has triggered the session between two clients. The role of SIP is completed successfully. He leaves his place for the following two steps namely coding and transmission of voice. The selected black frame shows the beginning of trade flow between the two RTP correspondents voice packets encoded in the standard G711 standard of the International Telecommunication Union ITU . - End of the call exchange SIP message BYE. The second application is to test the hierarchy of different communication protocols involved in a VOIP application. Figure 26 shows the order of the various protocols in a VOIP call session after analyzing the available statistics in the Ethereal program for each call made. Figure 26 shows that the first protocol involved in a communication VOIP is the SIP signalling protocol. The number of packets exchanged via SIP is eight. Thereafter the encapsulation IP UDP RTP to arrive at the Ethernet physical layer. The third application is to test the establishment of a call between two analogue phones via VoIP gateway. Figure 27 shows that communication is well established. Fig. 26. The hierarchy of protocols involved in the appeal Fig. 27. Call establishment Test of the proposed SOC gateway architecture In this section the following tests are done 1 Serial transfer test 2 Boot Uclinux under OR1ksim 3 Embedded network emulation and these applications are done using the software part of the opencores development platform. The application of the serial transfer test in the FPGA is done through the GDB. The communication protocol between the host and the architecture implemented on FPGA is done through the JTAG Proxy Server. An Opencores Opensource Based Embedded System-on-Chip Platform for Voice over Internet 167 Fig. 28. Results of the serial transfer test Fig. 29. Boot of Uclinux under ORlksim Fig. 30. FPGA board-PC Frame tansfer test result 168 VoIP Technologies Figure 28 summarize all .