Network Vip

Design of the digitized cable TV video service network

Design of the digitized cable TV video service network
With the progress of science and technology, the digitization of the cable TV network becomes one of the goals that we pursue, realize and have
Can develop and utilize channel resources in an all-round way in digitization of the line TV network, advance the application of the digital TV in a more cost-effective manner
With development of information industry, promote the intersection of TV and improvement of quality and enrich people’s spirit, culture life.
The realization of the digital TV public address system at present, the key lies in the code of the digital video flowing and in the unidirectional HFC network
In real time broadcast. In terms of this, can divide the digital television broadcasting into 4 systems to realize: The weaving of digital TV
Replying the modulation system which uses the system, digital TV of the video service systems of one yard of systems, digital TV, digital TV.
Code system of the digital TV. The system is mainly the video signal digitization that will imitated, and transmit to and look at in real time
Server or arriving to reply using device directly frequently. The system adopts radio grade MPEG- And 2 the intersection of code and way accord with DVB ASI different
Serial interface of step Transmit the standard. Encoding the effective assurance that the system is the digital program of the high quality of high quality.
Video service system of the digital TV. Should originally include NVOD and VOD system, NVOD offers real-time circulation to broadcast
Digital television program,to order to live to serve when offering VOD.
Replying using the system of digital TV. Compound the digital video flowing of form program of many ways into the digital video flowing of many programs of single way,
And accord with DVB ASI and transmit the standard and adjust the digital radio of realizing many programs of the program bandwidth.
Modulation system of the digital TV. Make the transmission of the digital program flow and transmit in the existing various -channel, raise the letter
The utilization ratio of the avenue and ability to resist interference, the quality of the warranty purpose audio frequency and video, and it is possible to offer for many kinds of additional business.
A design and construction priciple
In order to obtain the advantage in the constantly changeable competition and offer the good service result, the operation of the system has Israel
Make several characteristics: It is simple and convenient, fast in operation to manage the central business; Shorten serving to introduce to the market according to the user’s needs
Time; To the constantly changeable environment, make the fast response; Through offer many kinds of effective service, make sure with all
Different. So design the respect in the system, will follow the following principles:
1 Advance: Regard advanced person’s ripe digital television broadcasting treatment technology as the means and carry on construction, support the sound to look at
Application of frequently, data, NVOD/ VOD.
2 Standardization and opening: It accords with international and domestic DVBC standard that the procotol is adopted. Adopt and comply with the country
The standard networks of border and country design, it is apt to link with according with the standard apparatus; Adopt international ripe technology,
The advance of the security system, facilitate exchange and sharing of the program, the security of guaranteeing to make the investment.
3 Dependability and usability: Select high and reliable international products and technology for use, fully consider that different in the systematic procedure
Adaptability to changes and fault-tolerant ability when often, ensure the safety of whole system and reliable.
4 Flexibility and compatibility: Select for use, accord with international trend and software engineering of international standard, so that
The interconnected system has strong, highly reliable transplanting nature, advantages such as the expansibility,etc., guarantee to adopt in the development in future rapidly and appear newly
Technology,it is simultaneous it is interconnected with means since it offer for different extant networks and apparatuses.
5 Practicability and economy: In the system sets up, not merely should consider various business have been required actually up till now,
Should also fully consider the demand that business kind increases in the future. Proceed from practicability, economy, focus on the immediate objective
And long-term development, select the advanced apparatus for use, carry on the best performance association, construct a performance in limited investment
The best practicability system.
6 Security and privacy: Security and privacy of the network can be guaranteed from the following respects:
Distinguish with the password of the property right limit;
Control of the file access authority;
Select there is network equipment which encrypts the function in the apparatus, by encrypting the data to the important data;
The networking right of the mouth is managed to breathe heavily to network equipment, circuit, communication with the software of network management;
Accomplish double copies, a pair of power protection as to affair device and network equipment Hou, eye of centre.
7 Expansibility and opening ability: The system should have good expansion nature and upgrading ability to design, select for use
Apparatus with good upgrading ability and expanding.
2 video service systems
The scheme forms
On the basis of the above-mentioned design principle, can require, its technological scheme forms and should be stored, managed on the basis of the user
Pay attention to, transmit the ability that the figure compresses program and data.
The service system of the video should be by the video service
The output / 3 parts of input of device, video server NVOD and VOD software, DVB-ASI make up.
The recording, broadcasting and managing of the whole program is controlled in unison by the central control cabinet.
1 Server of the video
According to the requirement that NVOD and VOD program flows, can select the server adapting to for use, and dispose corresponding CPU, inside
Deposit and magnetic disc array, by storing required program quantity.
The intersection of system and structural respect in hardware, should adopt, have enormous the intersection of I/ O and handling capacity for realize the intersection of video and clothes at first
The platform where the affair environment employed, and can plug into the enormous video hard disk display storehouse, make more than one hundred complicated users request at the same time
Necessary enormous I/ O ability can be realized at the video. The most crucial one is still that the remarkable system of the server is soft among them
One and file system. Remarkable the intersection of file and system can manage as much as 1TB and the intersection of hard disk and storehouse of the above, namely can and so as to 1TB
The capacity of hard disk had is regarded as a unified file system. When storing the video file, the intersection of server and system software
Will type a video file very. Small chip, every different hard disks distributed in whole hard disk array
On the track, thus can be in order to handle with confidence when dozens of people need to request a TV programme or film at the same time. If every
A video serves the video velocity of flow that users get and can not be guaranteed, that is to have no enough bandwidth to obtain the data, place
The video requested will stop. The assurance of speed refer to, at the network, the more important thing is in and I/ O under system not merely
On the bus. Substantially as adopting and serving for chatting on video and designing specially system software, their and remarkable hardware system of server
The structure combines together, this solution of offering intact video service for user.
2 Server software of the video
The server software of the video should adopt the software that the world-leading Video Server software provider offered, enable it
Support NVOD, support VOD to serve at the same time.
Some the intersection of server and software can serve, offer, have a elasticity, not easy very much for cable TV and high Web of bandwidth frequently now at present
In the video service system that is popularized, and expanded the definition of the video service, has offered it from storing, managing, to the high quality
The transmission functions of quantity, interactive or half an interactive video system, have increased the support to digital television standard DVB,
Can apply to cable TV, education, amuses, commerce and other information exchange occasions extensively.
It accords with MPEG that the server software of the video can be offered through HFC network- 2 standard high quality, real-time NVOD sum
VOD video transmission serve, the management of its integrated video content, scalable video spread and send in, high-performance net
Hold management and operation in place with a net, store to manage.
The server software of the video has the following characteristics: The content of the backbone database is managed – -Offer the system management worker
Have, thus video content of carrying on the high capacity conveniently, often changing is installed and managed; The video returns tools
Can offer the real-time MPEG-2 video to return.
3 DVB ASI inputs / exports
Adopt the interface of international standard DVB ASI, the supreme speed reaches 270Mb/ s, convey SPTS and can also convey MPTS
Flow.
In a word, it is a brand-new field that the digitized wired television serves the network frequently, no matter in theory, return
It is on the performance of the software and hardware still in constant development, show the design of the network in developing too, performance of the network
Will be strengthened with the function constantly too.