XX Province Political and Legal Broadband Fiber Optic Information Communication Network

XX Province Political and Legal Broadband Fiber Optic Information Communication Network

1.                      Current situation

The third and fourth level communication networks of XX Provincial Public Security Bureau have undergone multiple upgrades and renovations. From renting DDN channels and E1 channels from county bureaus to police stations, they have been upgraded to PDH 100Mbps fiber optic communication networks. With the construction of the SkyNet project, more and more transmission bandwidth needs to be transmitted. Now, the transmission bandwidth of optical fibers has been upgraded to several line speeds of gigabit Ethernet. Due to the confidentiality requirements of the public security private network, several different functional Ethernet networks require physical isolation and achieve line speeds of 100M or 1000M.

Among the public security, procuratorial, judicial, and judicial organs in the political and legal system, only the Public Security Bureau has its own technical strength to establish its own communication system in the computer room. In other provinces, it relies on the basic strength of the Public Security Bureau to build a dedicated communication network for public security, procuratorial, judicial, and judicial systems, providing each system with its own physically isolated Ethernet system, while sharing the internal telephone system of the Ministry of Public Security in the political and legal system. At present, in addition to the public security system, other political and legal systems in XX Province generally use VPN private networks provided by operators to transmit network data. The business is relatively single, the confidentiality is weak, and it is not conducive to business expansion.

Building several systems together can not only save communication rooms, communication equipment, and reduce maintenance personnel, but also use the same core fiber optic cable to save fiber optic line rental costs. Generally, public security, procuratorial, and judicial departments are usually located in the same courtyard or not far apart at the township level. In 2010, Hebei Provincial Political and Legal Network organized a province wide bidding process to purchase equipment uniformly for each city's political and legal network. Provided internal telephone numbers of the Ministry of Public Security and local telephone numbers of the same bureau and political and legal system for judicial units in various townships, not only unifying their external image, but also facilitating centralized management. The system was built relatively early and generally uses a 155M SDH ring network system for transmission bandwidth. The reserved bandwidth for video transmission in the Skynet project is not very high, and the regions that will be tendered later will use a 622M SDH ring network system.

2.                      Suggested structure for the fourth level network

In this upgrade and renovation of the fourth level network, the central end is equipped with SDH ring network protection interface aggregation, and can access the public security telephone exchange network and the local telephone exchange network through No.1, No.7, PRI signaling. Adopt point to multipoint multi gigabit fiber optic access equipment for each township.

Due to the fact that video big data storage, processing, and processing servers can be placed in county bureaus, the technical strength of townships is weak, and the conditions of computer rooms are limited. Therefore, only county bureaus need multiple line speed gigabit networks for transmission to townships. County bureaus use 622M SDH rings to transmit processed video big data, as well as public security intranets, video conferences, etc. from county bureaus to city bureaus.

The upgraded fiber optic transmission system of XX Province's public security fourth level network adopts a transmission rate of 2.5G or 5G, providing 2 or 4 physically isolated Ethernet cables with a line speed of 1000M on the fiber optic cable, which can meet the high bandwidth requirements from county bureaus to townships. The large capacity bandwidth this time also provides sufficient channels for video transmission, including video conferencing, video surveillance, etc.

The use of 2.5G optical transmission has the characteristic of longer transmission distance compared to 5G optical transmission. Generally, the transmission distance of 5G and above is less than 10KM, and higher priced optical amplifiers are required for longer distances. And 2.5G can usually transmit 20KM, 40KM, 60KM, etc.

At present, each county is bidding separately, and the technical requirements are not unified. The telephone access method still uses the FXO and FXS distribution frame access methods, which have high costs, multiple fault points, and low telephone exchange efficiency. In the bidding process of Hebei Political and Legal Network, it is required to aggregate remote telephones and connect them to the public security telephone access system through China No.1 signaling, and to the local telephone operator's telephone network through China No.7 signaling and PRI signaling.

In addition, standard SDH technology can be directly connected to the operator's telephone exchange system.

In some important places, it is necessary to provide fiber optic loop protection function, that is, when there is one fiber short circuit on the fiber optic loop, all devices can still continue to communicate through the chain network. In some places, although ring networks are not applicable, it is required to provide dual optical port mutual backup on the fiber optic interface.

Providing high-definition video interfaces in fiber optic equipment is very convenient.

3.                      Public security checkpoint system

Nowadays, public security agencies in various regions have established convenient police booths, which should be connected to the internal information network and telephone of the public security. At the same time, in order to facilitate serving the people, Internet and local telephone services should also be provided. That is to say, it can provide 2 physically isolated Ethernet channels and at least 2 telephone access channels; Some require two networks: a road monitoring network and a public security internal office network. Usually, it is necessary to provide one two-way video channel to hold a simple video conference.

Our NTD421 is a data terminal with a fiber optic cable speed of 250M that can provide the aforementioned services. He can be used in pairs and can also connect to the higher-level network through GP_SPconv devices. GP_SPconv is a device that can be used independently or inserted into our company's G3CP integrated business platform. It also provides 2 telephone connections and 1 RS485 channel connection.

When the number of remote NTD421 is not large, access can also be achieved by inserting the GPuser disk on G3CP into the MP200 optical interface disk. 

In addition, our company's GTD441 is a 2.5G fiber optic line that can output two sets of line speed gigabit interfaces (each gigabit interface consists of one optical port and one electrical port, which can be switched), and the dual optical ports can be backed up to each other; It can also form a chain network or ring network, where two gigabit electrical ports and an optical port are on the same gigabit and can be exchanged with each other, and another gigabit channel is directly connected between the optical ports. GTD441 also provides 4-way telephone access and 1-way RS485 channel access.

GTD441 can be accessed by inserting the GP2000 optical interface disk into the GPuser disk on G3CP.