Only image sound is not enough meeting to require data solution Shenzhen Shard Software Technology Co., Ltd. www.szreach.com Ver. 1.1 22-May-03 1, Overview Today's society is the information society, who can transmit and get Information, whoever masters the opportunity in the fierce market competition. As a result, the conference television system is gone. The conference TV system transmits image, sounds, and data in real time, so that people in different regions have immersive feelings. In these three media, the sound has the highest priority, followed by data, and finally the image. The effect of the true conference can only be achieved by closely combining these three media. The conference TV system has gone over more than 10 years in China. From the earliest expensive H320 system to the current cheap H323 system, technology and cost performance have changed the earth. The earliest conference TV system is only a luxury of operators and government departments. In the present, SMEs are fully capable of withstanding and forming their own conference television systems. At present, most SMEs and government departments are actively preparing their own conference television systems, which can boldly predict that in the next few years, the development and popularization of conference television systems will fly, especially based on IP-based H323 conference television system. . On the other hand, users are constantly making new requirements in terms of the effects and specific applications of conference television. The previous conference is usually only an administrative meeting or a session, but it is required to have images and sounds, but now there is More training meetings and other meetings that require data sharing, the requirements for data are also higher and higher, especially distance education. At the same time, users also want to make full use of network resources, add more data services on existing network resources. Thus, adding data functions and data conferences in video conferencing will get more and more users' love. Since the conference television system is basically based on H320 / H323 international standards, the data conference must follow the relevant standards to interwork, T.120 protocol is the international standard of the data conference. At present, Netmeeting has become a standard for T120 data conferencing terminals. Almost all video conferencing manufacturers use NetMeeting as a terminal of the data conference, because Netmeeting itself is free, it is integrated in Windows, the user is very convenient. DSS (Data Share Server) Data Server is the first professional in accordance with T.120 standard data server products, which solves the problem of data sharing and collaboration in farewell users and manufacturers for a long time, and resolves hosting Netmeeting Various problems in the data conference. It is fully compliant with the standard of ITU-T T.120, which can be used alone or in combination with traditional conference television H.323 / H320 systems, and achieve the effect of the image. 2, T120 Technology Application T.120 Series Agreement Support point-to-point data conference, also supports multi-point data conference, with a series of very complex, flexible and effective features, even support non-standard application protocols . The T.120 protocol is independent of the specific network, using H.320 on the ISDN, using H.323 on the LAN and on the POTS, voice / data modem, using H.324 terminals can participate in the same T.120 conference. Different networks are only different from the protocol stack T.123, and the protocols above T.123 are independent of the network. Therefore, the protocol framework is almost suitable for all the current networks. The applications defined by standard T120 include: (1), application sharing and collaboration (T.128) (2), electronic whiteboard (T.126) (3), file transmission (T.127) (4), chat (T.121) (5), other custom applications (T.121) T120 technology have two solutions in conference television systems: 2.1, in-band mode, data and audio video stream shared bandwidth, The total bandwidth of the conference is the sum of audio, video and data.
When the terminal adds a data conference, its use of data bandwidth is specified by the MCU, such as 32kb / s, 64kb / s, 128kb / s, etc., no bandwidth of the audio video. If the meeting of 768kb / s can be specified, the audio bandwidth is 64kb / s (G.711 encoding), and the data band is set to 256kb / s, and the video bandwidth is 448kb / s. The bandwidth of the audio and video during the meeting is controlled by the MCU, and the data bandwidth is controlled by the T.120 server. During the MCU invitation terminal, the audio, video, and data channels are opened, and the audio and video channels are specified on the MP (multipoint processor) of the H323, specifying the data channel to the T.120 server. The conference process is: the advantage of the terminal H323MCU T.120 server band is: (1), attach T120 data functionality to the H320 / H323 conference, easy to control. (2) In the case of bandwidth, in the case of data congestion, the bandwidth of the data and the video can be dynamically adjusted to ensure normal audio. (3), the port of the acceptance of T120 can be exchanged via the ability to exchange the T120 (which is a 1503 port, which requires terminal support) to make the data more secure. (4), the data function can be synchronized with the image, the sound function can be synchronized. The disadvantage of the inner way is that: (1), there is a problem that the data server and the H323MCU fusion. (2) Once the H323 terminal is dropped, the T120 data function also disappears. (3) For some H323 terminals, it may not support the inner way. (4), T.120 Data Server If there is no bandwidth control, its data bursts will cause audio and video packet loss. 2.2, external manner is separated from the external manner, the data is separated from the audio video stream, and each occupied bandwidth. There is no relationship with terminals and MCUs. If the user wants to hold a data conference, a separate PC is required to perform data acceptance and delivery, all PCs for users who require data conferencing features are connected to a T.120 server. The currently common terminal software is Netmeeting software. Data occupies a separate bandwidth, not crowded with the bandwidth of the audio video. The establishment of the meeting is that the advantage of the terminal H323MCU T.120 server band is: (1), more users can participate in the data conference, not limited by the number of terminals. (2) Do not consider whether the H323 MCU and H323 terminals have a T120 function. (3) The data conference is separated from video conferencing, fault tolerance performance and stability. (4), it can be held separately. The disadvantage of the out-of-band is: (1), separation of images, sounds and data, can not be synchronized, inconvenient for operation and management. (2) If the bandwidth of the data is not limited, its burst data may cause the packet loss of the audio and video. (3) Two meetings must be held separately, and the operation is complex. 3. Data Sharing Server DSS Solution The DSS system consists of DSSSERVER and DSSManager. DSSServer is a server of 1U, DSSManager is a system's control management platform. DSSSERVER is the core part of the data conferencing system, which is responsible for the centralized processing and distribution of data, responsible for the scheduling and management of the meeting, making many users can easily join the data conference. It can be used in conjunction with different conference television systems to achieve graphic and meticulous. It is a data conference product built on a T.120 standard, supports both inner and outer ways. The in-band method can be compatible with the H323 / H320 / H324 device of any standard support T120 data channel, which is separate T120 DSS data server. DSSServer uses DSS system data sharing servers with the following advantages: L. Efficiency: Data conferencing, virtual office, remote teaching, single server equipment can achieve the maximum 32 meeting at the same time. l Interactive: electronic whiteboard, application sharing and collaboration, PowerPoint document demonstration, real-time question and answer, implementation interactivity. l Control: Support for the function of the Chairman of the traditional conference TV.
l Save costs: No need to travel long distance, saving the city or long-distance transportation fee, saving a difference. DSSManager Data Sharing Server DSS can be widely used in the following areas: L-Distance Education L Enterprise Daily Meeting L Government, Corporate Training L Securities Institutional Assembly and Road Down L provides online data conference between suppliers L E-commerce website online Sales Collaborative Development and Work 3.1, DSS and H323MCU combined with H323MCU provide secondary development API, which can easily fuse with the H.323 standard MCU, increase the data function of H323MCU. The H323MCU only needs to open the two-way data channel and point the data media channel address to the address of the DSS server, and the DSS data server will automatically complete the functions of the data conference. And the bandwidth of the data conference is strictly limited to the bandwidth specified by the channel. It solves the problems in the traditional inner way: (1), the meeting only needs to be held once, with audio and data and data. (2) To ensure that data and audio and video are fully synchronized. (3) You can match the H323MCU to implement QoS management function. Networking Mode: In-band-in-band network diagram 3.2, DSS's out-of-band way DSS can be run separately, convene a data conference, can be combined with the conference system, such as combined with the distance education system, providing data with control Meeting function. Since DSS provides Chair control and strict bandwidth control, it can be carried out simultaneously with other IP services. Networking mode: External Method Network Figure 4, DSS product function and performance standard and interoperability DSS system fully complies with ITU-T T.120 standards, can be interoperable with any product compliant with T.120 standards, can be NetMeeting's 2.1, 2.11, 3.0 and 3.01 versions are interoperable. Completely interoperate with the MeetingPoint of Vcon. Collaboration with Cuseeme is fully interoperable. Completely interoperate with iPower's data terminals. Compatible DSS systems with the MCU can meet the data functions in the conference television system with any MCU that meets the H.320 / H.323 standard. The MCU of the H320 requires a gateway (IP / ISDN) of T123. Stability DSS product is a server of 1U, using embedded design, fast start speed, stable system. Easy to configure the servers without serial port, etc., DSSManager can automatically search for servers and automatic configuration, and do not restart the server after configuration changes. Multi-Meeting Computer DSS system supports 32 sets of conferences simultaneously, and users can order the number of meetings as needed. Big users support a single DSS system to support 64 users simultaneously online. You can support more users at the same time through cascading, and users can order users as needed. Standard Data Features DSS System Support T120 System Standard Application Sharing and Collaboration, EDUC, Document Transfer and Chat. The Chair function can set up the chairman in the conference, only the Chairman has the power to perform data sharing, document transfer, whiteboard, chat, etc. Chaotic and disorder caused by multiplayers. Bandwidth Control DSS System Conference can specify bandwidth of the meeting, bandwidth between 64K ~ 1920K, when used at the same time as H323MCU, will not crush the bandwidth of audio and video, solve network packet loss problems due to TCP data burst. If you make a large amount of data with NetMeeting, the bandwidth bee value can reach more than 4M. Cascading DSS system supports cascading, up to 16 levels. Support slightly with conferencing mode users can join a meeting with other users instead of joining the meeting. Limit the application DSS server to limit the specific application of the meeting, for example, can specify a meeting that cannot transmit files and chat, even the Chairman does not have the function of being limited. Friendly user management simple and convenient user management, you can increase users, modify user information, delete users, etc. The network status of the user can be detected and displayed in real time in the conference.
Powerful Conference Template Management DSS system has a powerful meeting template management function, you can create, modify, and delete conference templates, configure a template for meetings, and you can meet directly, easy to use. The meeting security DSS system provides two-level meeting security guarantee, which can set it to the meeting or reject the user's addition, but also set a conference password, the user join the correct password to join the meeting. The drop-off user automatically invites the DSS conference to support the transfer user automatic invitation, and the invitation time is within 2 seconds to ensure the normal operation of the meeting. In a network of network quality, TCP connections will be disconnected because of congestion, and the DSS will automatically invite users to join the meeting to ensure that all users are always online. Detailed Terminal Information Display DSSManager can display detailed user information, including the meeting number, user number, alias, IP address, terminal name, Email address, location, conference bandwidth, whether it is the chairman and meeting functions. The terminal can be raised and lower according to various information. Convenient and concise meeting operation meeting operation is very simple and practical, the user's operating interface is convenient, using the whole button operation mode. The detailed system running logs Report a variety of system running logs in real time, logs are three categories: correct information, alarm information, error message, different types of logs different icons. The system log can also be saved in the file. Detailed system query information can query the product information of the system server, including server versions, number of members, users, and configured users and conference templates. Powerful QoS features can detect various network abnormalities of the system in real time, such as end users power down, network failure, etc. Automatic flow control and retransmission of TCP. The highest bandwidth limit system dynamic adjustment bandwidth can be combined with the H323MCU to make bandwidth through the firewall DSS system can pass the firewall to invite and receive users to join the conference system to provide the secondary development API interface DSS system to provide API interface, allow users to make users It is easy to integrate DSS systems into your own products. DSSManager is based on the API. Easy Upgrade DSSManager contains an upgrade file package that can be easily upgraded using this upgrade file package, and the upgrade file can be downloaded from the company website. It can be upgraded remotely. Upgrade contains server software upgrades (free) and user number upgrades (pay). Detailed and convenient help document users can easily switch between meetings and help documents on the management interface, helping documents include user manuals, technique white paper, common problem solutions, and company website navigation. 5, the technical leader of the DSS data server (1), the capacity is huge, in line with China's national conditions. (2), fully compliant with the T.120 standard. (3) Support the cascade of the data server, up to 16, expand system capacity, and networking more flexible. (4) Support Chair function, and ensure the normal or order of the meeting. (5) The conference bandwidth control function, does not account for the bandwidth of video and audio in the conference, and ensure the effect of the meeting. (6), powerful, especially suitable for centralized meeting scheduling and management. (7), it can be used with any standard H323MCU, and an API interface is also provided. (8), completely develop, customization easier, and it is easy to meet the custom needs of users. 6, DSS reliability (1), system uses hardware solutions, running stable and reliable. (2), an embedded operating system is used, and the running speed is fast and will not be attacked by the virus. (3), using multi-level meeting security methods to ensure the safety of the meeting. (4) Call success rate: 99.9%. (5) The data server MTBF is 100,000 hours, 24x7 work. 7, three network interfaces of interface and electrical characteristics: LAN: LAN port, connecting internal local area network. WAN: wide area network port, outlined network. Debug: Debug Network Port for manufacturers debugging.
