Tishreen University Journal for Research and Scientific Studies - Engineering Sciences Series Vol. (30) No. (2) 2008 2008 s VO ١٥٩
Tishreen University Journal for Research and Scientific Studies - Engineering Sciences Series Vol. (30) No. (2) 2008 Security of Computer Networks in Video Communications (Received 13 / 1 / 2008. Accepted 16/3/2008) ABSTRACT Dr. Tajaldeen jarkas * Dr. Adnan matermawi** Ramy Soultan*** This research studies video over internet protocols, which are becoming more common. More networks and legacy systems are being connected to public networks, allowing organizations to reduce costs and improve their offerings while allowing users to enjoy a variety of new and advanced services. The research also studies security as an important consideration when implementing VO because each element in the infrastructure is accessible on the network like any computer and can be attacked or used as a launching point for deeper internetwork and inside-the-organization attacks. I presented a vpn solution which traverses existing infrastructures and can realize connectivity without requiring firewalls and/or devices to be modified even for new protocols or revisions. Key Words : VO, Video over protocol,, Network Address Translator. * Professor, Department of Communication Engineering, Faculty of Mechanical and Electrical Engineering, Tishreen university, Lattakia, Syria. ** Assistant Professor, Department of Communication Engineering, Faculty of Mechanical and Electrical Engineering, Tishreen university, Lattakia, Syria. *** Postgraduate Student, Department of Communication Engineering, Faculty of Mechanical and Electrical Engineering, Tishreen university, Lattakia, Syria. ١٦٠
Tishreen University Journal. Eng. Sciences Series Full duplex VO VO s Syrian High Education Research Network Shern VO VO RTP Jitter RTP RTCP ١٦١
H225.0 RAS S RFC 3762 ENUM RFC 3219 TR DNS ITU-T [1] S ITU IETF S S S RFC 3261 [2] S S PSTN H320 S-I S-T S S S VO S S Instant messaging [3] LAN LAN ١٦٢
Tishreen University Journal. Eng. Sciences Series LAN T.120 Gateways Mcu GateKeepers GateKeeper Q931 H245 RAS RTP/RTCP ١٦٣
GateWays H242 H245 GateWay H221 H225 /H320 GateWay GateWays GateWay WAN LAN GateWay Q931 H245 GateWays /H320 ١٦٤
Tishreen University Journal. Eng. Sciences Series gatekeepers GatKeepers GateWays RAS RAS GateKeeper LAN LAN Email MCUs GateWays Zone Zone GateKeeper MCU MC MP GateKeeper [4] GateKeeper Multipoint Control Units(MCU) MCU MP H245 MC MC Multicast MC MP MC ١٦٥
Multicast Unicast MP MC MCU MCU H245 MCU H245 MP MCU Multicast MC [5] MP MC Multicast MC Multicast H245 RAS Q931 H245 RAS Q931 H245 ١٦٦
Tishreen University Journal. Eng. Sciences Series H245 H245 H245 ITU GateKeepers RAS Q931 GateKeeper RAS G711 64Kbps 56 G711 G728 16Kbps G722 - H261 H261 64 64 128 Kbps 100 Kbps H263 H263 H263 H261 H263 H261 H261 Hardware CIF, 4CIF, 16CIF ITU ITU ITU G723 H263 ITU Kbps H261 Kbps G728 H261 H263 QCIF H263 ١٦٧
ITU T.120 ITU T.120 [6] s Internet Firewalls [7] UDP TCP UDP TCP Virtual Slot TCP/UDP DNS 23 TCP Telnet 80 TCP HTTP 53 TCP UDP ١٦٨
Tishreen University Journal. Eng. Sciences Series TCP FTP HTTP TCP/ TCP [10] 16 Bit HTTP SMTP ١٦٩
[8] LAN s LAN [9] Nonroutable s Keep-alive ١٧٠
Tishreen University Journal. Eng. Sciences Series user1 user3 user2, user1 user3 user2 user1 user3 user2 user1 user2 OpenMCU.exe user3 ١٧١
user3 ١٧٢
Tishreen University Journal. Eng. Sciences Series Openphone.exe user1 user1 ١٧٣
Openphone.exe user2 user2 RAS Q931 GateKeeper UDP TCP TCP H.245 UDP RTP UDP RTP UDP RTCP ١٧٤
Tishreen University Journal. Eng. Sciences Series s FTP HTTP Routable s Routers ١٧٥
s Routing LAN LAN s Routable s Routable SSL- OSI SSL- SSL/TLS Static Key PlainText 10.8.0.2 PKI 10.8.0.1 s Static Key Static Key - - - - ١٧٦
Tishreen University Journal. Eng. Sciences Series UDP openvpn --genkey --secret static.key Local Area Connection n UDP TUN TUN - Windows Ping 10.8.0.2 Ping 10.8.0.1 Endpoint SSL- Client 185.110.120.1 10.8.0.2 UDP ١٧٧
10.8.0.1 185.110.120.2 RTP 10.8.0.1 MCU ١٧٨
Tishreen University Journal. Eng. Sciences Series MCU Server SSL- Server 185.110.120.2 10.8.0.1 Connected to:1 UDP 10.8.0.1 185.110.120.2 ١٧٩
185.110.120.2 VO VO VO Gateways DOS S ITU H.245 H.225 H.245 H.225 ١٨٠
Tishreen University Journal. Eng. Sciences Series VO 380Kbps [1] O'Reilly Media; 1 edition (June 30, 2005) ISBN: 0596008686 Switching to Vo"Paperback: 477 pages [2] Cisco Press (February 23, 2004) ISBN: 1587200929 "Taking Charge of Your Vo Project" Paperback: 312 pages [3] O'Reilly Media; 1 edition (December 1, 2005) ISBN: 0596101333 "Vo Hacks : Tips & Tools for Internet Telephony" Paperback: 306 pages [4] John Wiley & Sons, Inc. (April 2001) Format: Adobe Reader " Telephony with : Architectures for Unified Networks and Integrated Services" File Size: 7348 KB [5] VON Publishing LLC (October 2005) ISBN: 0974813001 "S Beyond Vo: The Next Step in the Communications Revolution" Paperback: 334 pages [6] Cisco Press; 1st edition (September 25, 2002) ISBN: 1587050145 "Voice- Enabling the Data Network:, MGCP, S, QoS, SLAs, and Security" : Hardcover: 224 pages [7] O'Reilly Media; 2nd edition (January 15, 2000) ISBN: 1565928717 "Building Internet Firewalls (2nd Edition)" Paperback: 869 pages [8] Addison-Wesley Professional; 1st edition (2003) ISBN: 0672322498 "RTP: Audio and Video for the Internet" Hardcover: 432 pages [9] Addison-Wesley Professional; 1st edition (October 13, 2000) ISBN: 0201615983 Paperback: 499 pages "SSL and TLS: Designing and Building Secure Systems" [10] ftp://ftp.isi.edu/in-notes/iana/assignments/port-numbers ١٨١
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