Construction of Voice Emergency Call Network for a Provincial Fire Brigade

1 Requirements Analysis
A provincial fire brigade plans to build a voice emergency call network covering provincial, municipal, and county levels. Currently, a certain city has 1 provincial brigade, 11 municipal fire detachments, and 257 fire squadrons.
Existing telecom E1 private networks are already in place between the provincial brigade and municipal detachments, as well as between municipal detachments and county squadrons. This project aims to deploy voice system equipment based on the existing E1 private networks to establish an emergency call system among departments at all levels. The main design requirements are as follows:

1. The provincial brigade provides 4 telephone lines, capable of making 4 simultaneous calls;
2. The provincial brigade provides 44 analog trunks, corresponding to the telephones of 11 municipal detachments;
3. Each municipal detachment requires at least 2 analog trunks to each squadron;
4. The entire province supports internal telephone switching, municipal detachments support local internal telephone switching, and each squadron also supports internal telephone switching;
5. Each squadron has 2 telephone lines aggregated at the provincial brigade via the transmission network and connected to the PSTN network;
6. The provincial brigade and detachment center equipment require dual E1 lines (primary and backup) for connection to the digital dispatch switch.

2 Solution Features
This solution is designed based on the SDH & PCM integrated system of Beijing Raytrans Digital Technology Co., Ltd. It mainly consists of the IDM MSAP-CP aggregation multi-service access platform, IDM series integrated service access equipment, and network management systems.
The solution features the following:

1. The entire system adopts TDM for voice access and transmission, offering high security and reliability, which is crucial for user units such as public security and fire departments with high system security requirements;
2. TDM-based voice access provides high real-time performance and low latency, enabling timely response to voice call requirements during major incidents for public security and fire units;
3. The MSAP-CP aggregation equipment provides a large-capacity cross-connect matrix supporting signaling processing, supporting digital trunk modes with No.7, No.1, PRI, and V5.2 signaling, as well as FXO analog trunk mode, and supports 4096*4096 non-blocking 64K timeslot cross-connection, enabling interconnection with local switching systems;
4. Additionally, the signaling gateway board of the MSAP-CP enables the division of independent number segments for each system;
5. Supports local internal telephone switching.

The overall network topology is shown in Figure 1 below.

Municipal Voice Access Design

For details, contact: 010-51668966