Field Intelligent Multi-Service Optical Transmission Equipment MTP-622
50 ms switchover to E1 link upon fiber break; one device aggregates voice, data, E1, and Ethernet
Field Intelligent Multi-Service Optical Transmission Equipment MTP-622, applied in the product showcase field, for industry customers' communication/transmission/dispatch equipment (to be further detailed based on documentation)
The IDM MTP-622 Field Emergency Optical Transmission Equipment is a field multi-service optical transmission device developed by Beijing Ruiguang Jiyuan Digital Technology Co., Ltd., and a representative product that Raytrans offers for military emergency communications and government private network scenarios. The device multiplexes E1 signals, audio signals, telephone/magneto signals, and wire-speed 100M Ethernet signals into STM-4 (622Mbit/s) optical fiber channels and E1 link channels for unified transmission, and supports intelligent mutual backup of transmission channels between the STM-4 optical fiber link and the E1 link, i.e., intelligent E1 link mutual backup. The device is mainly aimed at military and armed police field communications, emergency command private networks, and unattended sites in the field. The unit is designed for rapid setup and mobile relocation in field operations, and can be deployed as central office or remote-end equipment, providing product showcase and operational support for military emergency communications vehicle solutions and government private network optical fiber communication solutions.
The conclusion first: the IDM MTP-622 Field Emergency Optical Transmission Equipment uses one 622Mbit/s primary optical fiber channel plus one E1 backup channel to guarantee connectivity in the event of a fiber break. When the optical cable is interrupted, 2M services are automatically switched over to the E1 link within 50ms in hot standby mode, keeping voice and critical data services on the field private network uninterrupted. The unit adopts a 19-inch 3U modular chassis and consists of an SDH optical transmission unit, an E1 link interface control unit, an EOS unit, a PCM unit, an SNMP unit, and a protection switching unit. The standard configuration provides 4 channels of 10/100M Ethernet, 16 E1 circuit interfaces, 20 channels of voice, 1 V.35 interface, 2 V.24 interfaces, and 1 E1 link interface, plus 4 expansion slots for various service boards, so a single device can complete multi-service aggregation for a field private network. As a professional SDH equipment manufacturer, Raytrans integrates mature SDH equipment and MSTP technology into this model.
Key Specifications at a Glance: Optical port rate 622Mbit/s (STM-4, 2 hot-swappable SFP) · Single-mode transmission distance 40km · 16 E1 circuit interfaces · 4 Fast Ethernet ports · 20 channels of 2-wire/4-wire voice · 50ms switchover in hot standby mode (intelligent optical/E1 mutual backup) · Operating temperature -25℃~55℃ · Dual hot standby AC/DC power supply · 19-inch 3U chassis · Circular/aviation connector interface
Figure 1 shows the front of the 19-inch 3U chassis and the circular/aviation connector service interface layout of the IDM MTP-622 Field Emergency Optical Transmission Equipment. All service interfaces use circular/aviation connectors, which are reliable to plug and free from loosening. Combined with the shockproof, waterproof, and moisture-proof chassis, the device is suitable for rapid setup and frequent relocation at field sites, and can be flexibly deployed in military emergency communications vehicle solutions and various emergency communications sites.
What Service Interfaces Does the Field Emergency Optical Transmission Equipment Support
The standard configuration of the IDM MTP-622 Field Emergency Optical Transmission Equipment covers four types of service interfaces: voice, low-speed data, E1, and Ethernet. The voice and data interfaces all use circular/aviation connectors, which are reliable to plug and free from loosening. The interface layout is organized for rapid setup in field operations. Combined with the shockproof, waterproof, moisture-proof, and electromagnetic compatibility chassis, it can withstand repeated relocation in field sites and vehicle-mounted scenarios, making it a commonly used field emergency optical transmission equipment in emergency communications and military emergency communications vehicle solutions.
On the voice side, it provides 20 channels of 2-wire/4-wire voice interfaces (4 channels of 4-wire and 16 channels of 2-wire) at a rate of 64Kbit/s, configurable as hotline, magneto, subscriber, or trunk mode. The included 5-in-1 2-wire audio card provides 16 channels of 2-wire audio per card, and each 2-wire audio channel can be configured as FXO/FXS/hotline/magneto/2100 magneto mode, so magneto telephones and 2100Hz magneto telephones can be directly connected to the field wired communications network. On the data and transmission side, it provides 16 E1 circuit interfaces (75Ω unbalanced, rate 2.048Mbps, compliant with ITU-T G.703, HDB3 line coding, framing/unframing configurable, time slots configurable), 4 channels of 10M/100M adaptive Ethernet interfaces (RJ45, compliant with IEEE802.3, half/full-duplex), 1 V.35 interface (N×64Kbit/s, N≤30, supporting DCE and DTE modes), and 2 RS232/RS485 interfaces (asynchronous rate ≤19.2Kbit/s adaptive, synchronous rate 64K).
On the transmission side, it is equipped with 2 optical fiber line interfaces at 622Mbit/s. The optical interface is a hot-swappable SFP module, single-mode (multi-mode optional), with a wavelength of 1310nm or 1550nm, compliant with ITU-T G.957. There is also 1 E1 link interface (rate 2.048Mbps, compliant with ITU-T G.703) dedicated as the mutual backup channel for the optical fiber link. In addition, it provides 1 order wire interface for field service communication, 1 pair of synchronous clock interfaces (1 external input clock interface and 1 output synchronous clock interface) for maintaining clock synchronization with the upper-level transmission network, and 1 management interface that implements SNMP communication in accordance with IEEE802.3.
Intelligent E1 Link Mutual Backup Principle: How Long Does It Take for Services to Recover After an Optical Cable Interruption
Intelligent E1 link mutual backup is the core protection mechanism of the IDM MTP-622 Field Emergency Optical Transmission Equipment. When the optical fiber channel is normal, all services are transmitted over the 622Mbit/s optical fiber, and Ethernet services are configured with 2M bandwidth granularity, providing N×2M high-bandwidth Ethernet transmission. When the optical fiber channel fails, the protection switching unit automatically switches services to the E1 link channel, transmitting services at the specified 64K and N×64K. Ethernet services are then configured with 64K bandwidth granularity, providing N×64K low-bandwidth Ethernet service transmission. After the optical fiber channel recovers, all services automatically switch back to optical fiber transmission, with no manual intervention required throughout the process.
How long it takes for services to recover after an optical cable interruption depends on the link establishment mode of the E1 backup link: in hot standby mode, the switchover time is ≤50ms; in dial-up mode, establishing the E1 link takes ≤15s; in integrated network management mode, establishing the E1 link takes ≤50s. Hot standby mode is suitable for scenarios where the E1 link is pre-established and maintained, and the switchover is completed automatically inside the device by the protection switching unit, making it a common practice for fiber break protection on field private networks. Dial-up and integrated network management modes are used in scenarios where the E1 link needs to be established temporarily, establishing the backup channel first and then switching services.
| Link Establishment Mode | Time for 2M Services to Switch Over to the E1 Link | Applicable Conditions |
|---|---|---|
| Hot standby mode | ≤50ms | The E1 link is pre-established and maintained; the switchover is completed automatically inside the device |
| Dial-up mode | ≤15s | The E1 link needs to be established temporarily by dial-up |
| Integrated network management mode | ≤50s | The E1 link is established through integrated network management |
In terms of bit error characteristics, the optical fiber link complies with ITU-T G.826, which can be used to evaluate the transmission quality of the optical fiber channel. Switchover status and link alarms can be viewed remotely through SNMP network management, based on which duty personnel can monitor link conditions and determine whether personnel need to be dispatched. For unattended sites in the field, link self-healing and network management alarms are fundamental capabilities for ensuring mission continuity.
Figure 2 is a networking topology diagram of central office and remote-end Field Emergency Optical Transmission Equipment with intelligent mutual backup transmission over STM-4 optical fiber and E1 links, showing the automatic switchover relationship between the primary optical fiber channel and the E1 backup channel.
Main Functions of the IDM MTP-622
The functions of the IDM MTP-622 Field Emergency Optical Transmission Equipment are designed around channel mutual backup, multi-service access, telephone switching, network management and monitoring, and military-standard environmental adaptability. The main function items are listed in the table below.
| Function | Description |
|---|---|
| Chassis and expansion | Adopts a standard 19-inch 3U chassis structure with a modular design; service access slots are universal; in addition to the standard configuration, 4 expansion slots are provided to accommodate various required services according to user configuration requirements |
| Intelligent mutual backup between E1 link and SDH optical link | Supports intelligent mutual backup between the E1 link and the SDH optical link; when the optical cable fails, services are automatically switched over to the E1 link, and automatically switched back after the optical fiber recovers |
| Unified multi-service access | Supports STM-4 optical interfaces, E1 services, FXS/FXO services, magneto services, V.24 services, V.35 services, and Ethernet services, and provides an E1 link interface as a backup transmission channel |
| 5-in-1 2-wire audio card | Provides 16 channels of 2-wire audio per card; each 2-wire audio channel can be configured as FXO/FXS/hotline/magneto/2100 magneto mode |
| Local telephone switching | Supports local telephone switching and provides 1~2 E1 digital trunk interfaces, supporting SS7, PRI, and No.1 signaling |
| SNMP network management and northbound interface | Supports the SNMP network management protocol and remote device service configuration; supports the northbound interface (NBI), provides alarm information upload, and is capable of accessing the military-wide optical fiber communication transmission network management system |
| Power supply and optical port redundancy | Supports dual hot standby power supplies; supports optical port replaceability, with optical ports using hot-swappable SFP modules |
| EMC electromagnetic compatibility | The EMC design complies with the relevant provisions for Army ground equipment in GJB151A-1997 "Electromagnetic Emission and Susceptibility Requirements for Military Equipment and Subsystems"; electromagnetic emission and susceptibility tests comply with the relevant provisions of GJB152A-1997 |
| Environmental adaptability | Vibration, shock, and drop requirements meet the relevant provisions of GJB367A-2001 "General Specification for Military Communication Equipment", with good waterproof and moisture-proof design |
| Interface form | All interfaces use circular/aviation connectors, which are reliable to plug, suitable for rapid setup and mobile use in field operations |
IDM MTP-622 Technical Specifications
Line and Service Interface Parameters
| Item | Parameter/Specification | Description/Applicable Conditions |
|---|---|---|
| Optical fiber line interface | 2, rate 622Mbit/s, compliant with ITU-T G.957 | Optical interface is hot-swappable SFP, single-mode (multi-mode optional), wavelength 1310nm or 1550nm |
| Optical interface technical parameters | Transmit optical power -15~-8dBm, receiver sensitivity better than -32dBm | Standard single-mode transmission distance 40km; long-distance optical modules can be optionally installed for longer transmission |
| E1 link interface | 1, rate 2.048Mbps, compliant with ITU-T G.703 | Used as the mutual backup transmission channel for the optical fiber link to implement intelligent E1 link mutual backup |
| E1 circuit interface | 16 (75Ω unbalanced), rate 2.048Mbps, compliant with ITU-T G.703 | Line coding HDB3, framing/unframing configurable, time slots configurable, used for 2M service access |
| Ethernet interface | 4 RJ45, 10M/100M adaptive, compliant with IEEE802.3 | Half/full-duplex, wire-speed 100M Ethernet signal transmission |
| V.35 interface | 1, rate N×64Kbit/s (N≤30), compliant with ITU-T V.35 | Supports DCE and DTE modes |
| RS232/RS485 interface | 2, asynchronous rate ≤19.2Kbit/s adaptive, synchronous rate 64K | Compliant with RS232/RS485 interface standards |
| 2-wire/4-wire voice interface | 20 channels (4 channels of 4-wire, 16 channels of 2-wire), rate 64Kbit/s | Modes: hotline, magneto, subscriber, trunk |
| Order wire interface | 1 | Used for field service communication |
| Synchronous clock interface | 1 pair, 1 external input clock interface and 1 output synchronous clock interface | Used for clock synchronization with the upper-level transmission network |
| Management interface | Interface characteristics comply with the relevant provisions of IEEE802.3, communication protocol SNMP | The network management system provides a northbound interface (NBI) and is capable of accessing the military-wide optical fiber communication transmission network management system |
Power Supply and Unit Parameters
| Item | Parameter/Specification | Description/Applicable Conditions |
|---|---|---|
| Power supply mode | AC 220V (187V |
AC and DC power supply, supporting dual hot standby power supplies |
| Operating temperature | -25℃～55℃ | Operating ambient temperature; storage temperature -40℃～75℃ |
| Relative humidity | ≤95%, non-condensing | Together with the wide-temperature specification, determines field adaptability |
| Optical cable link switchover time | 2M service switched to E1 link: hot standby mode ≤50ms, dial-up mode ≤15s, integrated network management mode ≤50s | Service automatically switches back to the optical fiber after the optical fiber channel recovers |
| Bit error characteristics | Optical fiber link complies with the relevant provisions of ITU-T G.826 | Used to evaluate optical fiber channel transmission quality |
| Unit dimensions | Height ≤3U | Can be installed in a 19-inch standard cabinet |
Typical Application Scenarios
Military and Armed Police Field Communications, Emergency Command Private Network
Military and armed police field communications and emergency command private networks usually deploy field emergency optical transmission equipment in paired configurations at the central office and remote end, with the transmission line consisting of STM-4 optical fiber and E1 links forming mutual backup transmission channels. The central office equipment can access the telephone switching network through FXO analog trunk or E1 digital trunk (supporting SS7, PRI and No.1 signaling), access the IP network through a Fast Ethernet interface, and simultaneously provide V.35, V.24, hotline phone, ordinary telephone, E1 and 4-wire audio service access; the remote equipment is deployed at field training bases or installed on field communication vehicles, providing access to the same types of services. This architecture is exactly a typical military emergency communications vehicle solution, and also an important product showcase form in the emergency communications system.
As a field-mobile STM-4 optical transmission equipment, when the optical fiber is normal, voice, E1 and data services are all transmitted over the 622Mbit/s optical fiber; when the optical cable is damaged or interrupted, services are automatically switched to the E1 link for fallback transmission within 50ms, and command contact is not interrupted during optical fiber emergency repair. The equipment supports SNMP network management and northbound interface (NBI), alarm information can be uploaded, and it has the capability to access the military-wide optical fiber communication transmission network management system, making it easy for superior network management to uniformly grasp the status of field nodes.
Industrial Private Networks Such as Electric Power, Oil and Gas, and Railway
Industrial private networks such as electric power, oil and gas, and railway have sites distributed along the line with large spacing between stations. E1 channels are often used between sites to carry protection and dispatching signals, and Fast Ethernet is used to carry IP data. Field sites generally lack equipment room conditions and dedicated duty. The field emergency optical transmission equipment IDM MTP-622 provides 16 E1 circuit interfaces (compliant with the ITU-T G.703 standard) and 4 10M/100M adaptive Ethernet interfaces, and can simultaneously carry inter-station 2M services and IP data. One device completes multi-service aggregation, reducing the number of devices in cabinets along the line.
The -25℃~55℃ operating temperature range, AC 220V and DC -48V/DC 24V AC/DC power supply modes, together with the chassis structure and circular/aviation connector interface that meet the vibration, shock and drop requirements of GJB367A-2001, are suitable for deployment in cabinets along the line, on vehicles and at temporary sites; when the optical cable is damaged during road construction or extreme weather, services are automatically switched to the E1 link, and voice and critical data remain continuous.
Civil Air Defense, Emergency Management and Border/Coastal Defense Unattended Sites
Civil air defense, emergency management and border/coastal defense unattended sites are usually located in remote areas and unattended for long periods, with concentrated requirements for power supply redundancy, environmental adaptability and on-site maintainability. The field emergency optical transmission equipment IDM MTP-622 supports dual hot standby power supplies, with two power feeds connected simultaneously; if either feed loses power, the other continues to supply, and services are uninterrupted; the optical port uses a hot-swappable SFP module, supporting optical port replaceability, so on-site replacement of the optical module can eliminate optical-side failures without returning to the factory.
The unit operating temperature is -25℃～55℃, storage temperature -40℃～75℃, relative humidity ≤95% non-condensing, the EMC design complies with the relevant provisions of GJB151A-1997 for army ground equipment, electromagnetic emission and susceptibility tests comply with the relevant provisions of GJB152A-1997, and it meets the vibration, shock and drop requirements of GJB367A-2001, with good waterproof and moisture-proof design. Sites can send telephone, E1 and Ethernet services back to the rear command node; when the optical cable is interrupted, services are automatically switched to the E1 link, and with SNMP network management the link status can be checked remotely, reducing the frequency of sending personnel to the site.
Figure 3 shows a schematic of the application scenario in which field communication vehicles and unattended sites in the field deploy the field emergency optical transmission equipment, demonstrating the mutual backup networking relationship between the central office equipment and the remote equipment via STM-4 optical fiber and E1 links.
Why Choose It for Unattended Sites in the Field: Three Differentiated Values
The three differentiated capabilities of the field emergency optical transmission equipment IDM MTP-622 are the 50ms intelligent mutual backup fiber break fallback, the multi-service aggregation of a single 3U device, and the maintenance-free design of wide temperature, dual power supplies and replaceable optical ports. The corresponding user value of each is shown in the table below.
| Differentiation Point | Value to Users |
|---|---|
| Automatic switchover to E1 link within 50ms of optical cable interruption | Field private network services are uninterrupted, and voice and critical data remain continuous during optical cable emergency repair |
| A single device integrates STM-4, 16 E1, 20 voice and 4 Ethernet multi-services | Private network integration uses half the chassis, with voice, magneto, E1, data and Ethernet multiplexed within the same device |
| Dual hot standby power supplies + replaceable optical ports, reliable operation at -25℃~55℃ unattended in the field | Maintenance-free design for field sites; if either power feed loses power, services are uninterrupted, and optical-side failures can be handled by replacing the optical module on site |
No service interruption on fiber break relies on the dual-channel mutual backup mechanism, rather than improving the reliability of a single link. When the primary optical fiber channel is interrupted, the protection switching unit automatically switches the 2M service to the E1 link; in hot standby mode the switchover time is ≤50ms, and both switchover and switchback are completed automatically by the device without on-site personnel intervention, making it particularly suitable for unattended mobile or remote sites such as field communication vehicles, border/coastal defense and civil air defense, and it is also the core transmission guarantee of the military emergency communications vehicle solution in emergency communications scenarios.
The significance of multi-service aggregation in a standalone unit lies in reducing chassis and wiring. The standard configuration of the unit provides 16 E1, 4 10/100M Ethernet and 20 voice channels (4 4-wire and 16 2-wire), plus 1 V.35, 2 V.24 and 4 expansion slots. V.35 and V.24 data, magneto and hotline phones, 2M services and IP data are multiplexed within the same 19-inch 3U device, so sites do not need to stack separate transmission equipment for each type of service, and wiring and the variety of spare parts are reduced accordingly. For government private network optical fiber communication solutions that need to integrate the multi-service transmission capabilities of SDH equipment, MSTP and others, this standalone unit aggregation form can significantly simplify the site product showcase and deployment structure.
Figure 4 shows the overall layout of the optical ports, E1, voice and data interface boards on the rear of the field emergency optical transmission equipment chassis, for on-site quick verification and wiring reference by interface.
Selection and Deployment Recommendations for Field Emergency Optical Transmission Equipment
During selection, it is recommended to check according to the following four steps to avoid mismatch between the configuration and the actual service volume and link conditions:
- Count service types and number of channels: first confirm how many E1 channels, how many telephone/magneto channels, how many Ethernet channels are needed, and whether V.35/V.24 data is required. The standard configuration is 4 10/100M Ethernet, 16 E1, 20 voice (4 4-wire and 16 2-wire), 1 V.35 and 2 V.24.
- Confirm expansion requirements: when the number of service channels exceeds the standard configuration, use the 4 expansion slots in the chassis to insert the required service boards; the slots are universal and can be accessed according to configuration requirements.
- Check transmission distance and backup channel: within 40km, use standard single-mode optical modules; when a longer distance is required, install long-distance optical modules; when fiber break fallback is required, prepare the E1 bearer channel at the same time, and clarify whether to use hot standby, dial-up or integrated network management mode to establish the E1 link, because the switchover times of these three modes are ≤50ms, ≤15s and ≤50s respectively.
- Check interface form and operating environment: confirm whether a circular/aviation connector interface, military-standard EMC and waterproof and moisture-proof design are required, and whether the site power supply mode is AC 220V or DC -48V/DC 24V, and whether dual hot standby power supplies and replaceable optical ports are required.
If you are unsure about the required number of service channels, transmission distance or whether the E1 backup link is sufficient, you can provide the manufacturer with the optical fiber length, line loss and service list, based on which the selection solution can be calculated. As a professional SDH equipment manufacturer, Raytrans can provide complete selection support from SDH equipment and MSTP to field emergency optical transmission equipment for military emergency communications vehicle solutions and government private network optical fiber communication solutions, and assist in calculating the configuration mode of E1 link intelligent mutual backup.
