In-depth Analysis and Era Significance of FTTD All-Optical LAN

I. Main Technical Features

Based on the company’s invention patent “FTTD All-Optical Network Communication System” and a number of utility model patent products developed around this system, a network architecture is built that is based on traditional Ethernet technology, adopts an innovative low-cost structure and simplified construction mode, and completely subverts the deployment logic of traditional local area networks. Its core lies in realizing high-performance, low-energy-consumption, and low-maintenance network upgrades with an extremely simplified optical network architecture, and the technical feasibility has been verified in practical applications.

Notable FTTD Implementation Projects:

Wuyi County Construction Bureau (Oct 2016): Zero maintenance in the first two years post-handover; no network issues to date.
Wuyi County Tax Bureau (Sep 2019): Over five years of operation with maintenance costs under ¥10,000 (primary failures attributed to power supply issues).
Wuyi Vocational and Technical School (Aug 2021): Network maintenance costs under ¥10,000; minimal component replacements (e.g., optical modules).
Wuyi Shuxi & Baiyang Tax Offices (Oct 2023): Zero maintenance required since deployment.

1. Innovations in FTTD All-Optical Network Architecture

Equipment Room Core Layer: Network cabinet, Optical Distribution Frame (ODF), network firewall, router, and core all-optical switch.
Optical Cable Lines: Optical cables from the ODF to each floor or weak current room, together with indoor drop cables, are fixed in the optical cable direct fusion box. Using an optical fiber fusion splicer for one-to-one direct fusion, a point-to-point direct connection between ODF ports and room optical ports is formed.
Terminal Equipment: 86-type optical-electrical outlet transceiver with one optical port and multiple electrical ports (Utility Model Patent: CN216959874U, a type of optical fiber transceiver, featuring 1 optical port and 2, 4, or 8 electrical ports, supporting plug-and-play Gigabit transmission with power consumption less than 3W, configured according to terminal application requirements; it has also obtained U.S. and EU design registration certificates, with international registration number: DM/2298077), installed on-site using optical fiber SC connector cold splicing technology.

The FTTD all-optical network is completed with the above three components. The architecture of the Ethernet LAN FTTD(R) fiber-to-the-desktop all-optical network communication system is simple, which simplifies equipment in the equipment room, reduces energy consumption, and lowers equipment room construction costs.

Moreover, only one or two cores of indoor optical fiber need to be laid in each office area or room, and work terminals can be connected through the optical outlet switch, eliminating the need for laying a large number of network cables.

Optical cables have small diameter and light weight, so there is no need to install large-size cable trays, reducing engineering construction costs. Replacing network cables with optical fibers overcomes the limitations of copper network cables in terms of distance and speed, reduces the usage of network cables, and saves a large amount of copper (the cost of optical fiber cables is already very low, even less than one-tenth of that of Category 6 or 7 network cables, with higher cost performance).

It also significantly reduces the workload of engineering wiring as well as material and labor costs. Meanwhile, replacing network cables with optical fibers eliminates the phenomenon of uneven quality and the use of shoddy products in the market for network cables.

2.System Advantages

Against the policy backdrop of “Double Reduction” and “cost reduction and efficiency improvement”, coupled with the applications of big data, intelligent AI, and high-definition videos, enterprises have put forward higher requirements for the efficiency, security, and cost control of office networks.

The 86-box-installed optical-electrical outlet transceiver with one optical port and multiple electrical ports launched by Zhejiang Jindong Communication solves the problem of the “last mile” in all-optical networks, blazing a unique and innovative path in the field of local area network construction.

The company’s design starting point is as follows: The completion of a building requires planning for its functional use over many years, while considering other various application needs to achieve equivalent performance. For example, in the design of intelligent building transmission lines, the advantages of optical cable lines such as high bandwidth, low latency, easy expansion, light weight, abundant resources, and easy management are taken into account, and at the same time, the avoidance of duplicate construction is considered.

Zhejiang Jindong Communication adopts an Ethernet architecture. The equipment room only needs all-optical port switches (such as 10G uplink + 1000M optical ports), which are directly connected to terminal optical outlet transceivers through end-to-end optical cables, eliminating the need for aggregation layer switches and patch panels, thus reducing the space occupied by the equipment room by 70%.

In the equipment room, 1000M all-optical port switches are connected to optical cable ODF distribution frames. Optical cables and indoor drop cables are directly fused and connected in the weak current room through direct fusion splicing boxes. When connecting to indoor desktops, the self-developed and produced patented product – optical fiber 1000M outlet transceiver (1 optical port with multiple electrical ports) is used for FTTD networking.

This solution is highly flexible: if the network needs to be upgraded to 10G, only optical modules and outlet transceivers need to be replaced without adjusting the lines. For large-scale office environments, block-based FTTD aggregation is adopted, with 12-core backbone optical cables connecting to the core switches in the main equipment room. This network architecture has significant advantages: it is not only simple but also reduces equipment in the equipment room, with low optical cable costs, mature construction technology, and low entry barriers. Traditional network technicians can take up construction work after two days of training.

Moreover, Zhejiang Jindong Communication combines a 100% domestically produced system integration solution and cooperates with well-known domestic manufacturers to ensure product quality and technical support.

3.Comparison Between Ethernet and PON:

3. 1 Technical Rationality Analysis of FTTD All-Optical Ethernet Solution

Significant Cost Advantage: Currently, the cost of optical fibers and cables has dropped to a historical low. The FTTD solution adopts a point-to-point architecture, using single-mode optical cables to directly connect to the 弱电间 (weak current room) of each floor. Each office is equipped with 2 single-core tight-buffered optical cables leading to desktop terminals, reducing material costs by more than 40% compared with traditional copper cable solutions. Combined with cold splicing technology, the construction period is shortened by 40%, resulting in a significant comprehensive cost advantage.
Advanced Technical Architecture: The system adopts a three-level architecture of “core switching center – regional aggregation point – terminal node”. The backbone optical cable supports transmission via single-mode single-core optical modules, enabling gigabit bandwidth to reach the desktop directly. Through the collaborative deployment of domestically produced all-optical port aggregation switches and 86-type box transceivers, a pure optical transmission link is built, ensuring the stability and low-latency characteristics of data transmission.
Equal Emphasis on Security and Scalability: The design features physical isolation of internal and external networks through independent optical cables, combined with VLAN logical division, forming a dual security protection system. The system reserves 20% fiber redundancy capacity, supporting smooth upgrading to 10-gigabit networks in the future. Bandwidth doubling can be achieved simply by replacing terminal equipment, thus protecting existing investments.

3.2 Multi-Dimensional Comparison Between FTTD and PON Networking

Comparison Dimensions	FTTD Solution	PON Network
Wiring Flexibility	Two indoor drop fiber cables are placed in each office, running to the telecom room. With internal and external networks in mind, these cables are directly connected to the distribution frame in the equipment room via fiber fusion splicing. The ports on the distribution frame and those in the office form a point-to-point direct connection, ensuring low optical loss in the link. Only a fiber optic splice closure needs to be installed in the telecom room, and the telecom room can even be dispensed with, taking up little space.	Two indoor drop fiber cables are placed in each office, running to the telecom room. For setting up internal and external networks, optical splitters are connected to the equipment room via fiber jumpers, leading to relatively high optical loss. The telecom room requires a network cabinet to house the Optical Distribution Frame (ODF), thus occupying a large space.
Wiring Flexibility	In the office, the one-fiber multi-electrical optical socket transceiver, specially designed for socket box installation, is easy to set up (can be completed in five minutes). The network is plug-and-play, supporting full Gigabit operation. Fiber optic cables can be reserved inside the box, and different specifications (1-fiber 2-electrical, 1-fiber 4-electrical, 1-fiber 8-electrical) can be flexibly selected for adaptation according to the number of devices. The socket transceiver can be installed in an 86-type box, with good cable concealment and high aesthetics.	The Optical Network Unit (ONU), commonly known as an “optical modem,” requires technical configuration for use and needs to take optical loss into account. Its connection requires pigtail jumpers, which are exposed outside the socket. It is relatively large in size and installed on the wall. When used with combined office desks, additional switches are often needed for expansion. ONUs require independent power supply, are relatively large in size, and have low aesthetics.
Bandwidth Performance	Modern office applications such as big data, AI intelligence, and high-definition video transmission require low-latency and high-speed networks to improve work efficiency. With the point-to-point connection method, switch ports are directly connected to one-fiber multi-electrical optical socket transceivers, which can ensure that each computer obtains stable and high-speed bandwidth. This guarantees the instant transmission of large files and the smooth operation of high-definition video conferences.	The point-to-multipoint architecture allows multiple terminals to share fiber bandwidth. When the number of computers increases or in scenarios with high usage rates, bandwidth insufficiency and network congestion are prone to occur, seriously affecting work efficiency. It is just like a water pipe connected to many hoses at the same time—when all are turned on, the water flow becomes very small.
Troubleshooting	The fault location of point-to-point connections is accurate and rapid. Technicians can quickly determine whether the fault lies in a specific tight-buffered fiber optic cable or in an optical outlet transceiver with one-fiber-to-multiple-electric ports. The scope of troubleshooting is small, which greatly shortens the time spent on fault diagnosis.	When multiple ONUs share a link and a fault occurs, it requires highly skilled technicians to troubleshoot the OLT, optical splitter, each ONU, and related links in sequence. Involving a large number of devices and links, the fault troubleshooting is relatively time-consuming and affects the normal operation of office services.
Network Upgrade	During an upgrade, it is only necessary to replace the higher-performance optical modules in the equipment room and the compatible one-fiber-to-multiple-electric optical outlet transceivers in the office to achieve bandwidth upgrade, without the need for re-wiring the network. This ensures strong business continuity.	In contrast, an upgrade requires reconfiguring the optical splitter, replacing OLT and ONU devices, and even re-planning the fiber optic links. The project is complex and costly, and the upgrade process has a significant impact on existing services.
Security	In the point-to-point connection mode, each office’s network is independent, avoiding being affected by network attacks or security vulnerabilities in other offices.	When multiple users share a link, once a security issue occurs at the optical splitter or a user end, it may threaten the network security of the entire area, making security protection more difficult.
Device Compatibility	Ethernet technology is already very mature. Different brands of all-optical switches, optical fibers and cables can be freely selected, all of which can be well adapted to the one-fiber-to-multiple-electric optical outlet transceivers and can also be perfectly integrated into the existing Ethernet equipment system.	ONU devices usually need to be used with OLT devices. After equipment selection, they rely on the compatibility between OLT and ONU of specific manufacturers, resulting in poor cross-brand interoperability.
Requirements for Technicians	The switch supports plug-and-play functionality and adopts conventional Ethernet technology, enabling technicians to get familiar with it quickly. Even ordinary technicians can rapidly master the installation, debugging, and maintenance of FTTD networks, and can learn to operate the one-fiber-to-multiple-electric optical outlet transceivers within half a day.	In contrast, the technology involved is relatively advanced, and there is a shortage of skilled technicians. Learning and mastering this technology requires more time and cost input, which is not conducive to the daily network operation and maintenance work.
Business Continuity Guarantee	In the point-to-point connection mode, a fault in one connection will not affect the normal operation of other information points, thus ensuring the continuity of office services.	However, if a fault occurs in the optical splitter or the backbone link, it may cause network outages for a large number of users, seriously affecting business continuity.
Capability to Support Real-Time Services	A stable point-to-point connection can ensure low-latency and packet-loss-free data transmission, meeting the needs of office services with extremely high real-time requirements.	Due to the bandwidth-sharing nature, in scenarios with high-concurrency real-time services, it is difficult to guarantee that each terminal can obtain low-latency and high-quality network services.
Autonomy in Network Planning	In the case of FTTD, offices can independently determine the scale and pace of FTTD network construction according to their own business development plans. They can flexibly configure one-fiber-to-multiple-electric optical outlet transceivers of different specifications based on the needs of different areas.	In contrast, the construction requires overall planning of ONU, optical splitter, OLT and other devices, and is limited by the manufacturer’s equipment, making it difficult to adjust the construction scale and pace. Moreover, equipment maintenance and replacement need to be bound to specific manufacturers.
Technical Training and Handover	The training content is relatively limited, mainly focusing on the use and maintenance of Ethernet all-optical equipment, and the handover process is relatively simple.	In contrast, the training content is more extensive, including PON technical principles, equipment configuration, fault troubleshooting, etc., with a longer training duration, and the handover process is relatively complicated.
Long-Term Cost-Effectiveness	The structured cabling system can remain in use for 30 years without the need for rewiring. Although the initial investment in equipment is relatively higher, its long-term cost-effectiveness is better than that of PON networks due to fewer faults, lower maintenance costs, and convenient upgrades. The one-fiber-to-multiple-electric optical outlet transceivers are of high quality, have a long service life, and come with worry-free after-sales services, resulting in extremely low maintenance costs.	In long-term use, however, high costs may be incurred due to frequent upgrades and transformations, fault troubleshooting and repairs, etc. The maintenance costs of ONUs and optical splitters account for a large proportion.
Initial Construction Cost	The local area network enables each network terminal to meet the gigabit transmission requirement for both upstream and downstream simultaneously. The acceptance standard is that the concurrent detection of multiple terminals meets the criteria. It is estimated that the cost is at least 30% lower than that of PON networking. If applied to 1,000 terminals, the cost will be 40% lower.	To meet the simultaneous gigabit concurrent transmission, 10G PON is required, and each PON connection cannot use an optical splitter with a splitting ratio higher than 1:8. Meanwhile, there is a risk of excessive loss in splitter connections. The expansion of OLT PON ports and the increased usage of splitters lead to higher costs. In addition, “optical modems” need to be used with small switches for expansion.

This analysis is based on the practical application of the company’s founder in communication lines and network engineering for many years. The FTTD Ethernet local area network architecture has obtained an invention patent, and combined with multiple AI algorithms, it has been summarized through more than ten in-depth explorations and verifications.

The Ethernet all-optical solution is comprehensively superior to the PON solution in core dimensions such as technical feasibility, cost control, and ease of operation and maintenance, making it the optimal solution for enterprise-level all-optical local area network construction.

4.Scope of Application:

All fiber optic networks including Fiber to the Desk (FTTD), Fiber to the Room (FTTR), and Fiber to the Terminal (FTTT).

II. Invented and Manufactured Products:

(1) Invention Patent: CN117479059A – A Fiber-to-the-Desktop All-Optical Network Communication System.

It is an all-optical local area network based on Ethernet architecture, consisting of a core switching layer (or aggregation layer) + optical cable lines + one-fiber multi-electrical port socket transceivers.

(2) Utility Model Patent: CN216959874U – An Optical Fiber Socket Optoelectronic Transceiver, with U.S. and EU design registration certificates and an international registration number: DM/2298077.

The panel-type optical socket transceiver is designed for universal 86-type junction boxes. It is installed and fixed against the outer side of the universal 86-type socket back box, without occupying the space of the back box, which facilitates the back box to be used for reserving extra wires.

The panel-type optical socket switches are available in three models: 1-fiber-2-electric, 1-fiber-4-electric, and 1-fiber-8-electric, which can be flexibly configured according to the usage needs of different terminals, and are practical and aesthetically pleasing.The optical port adopts an SC interface, allowing on-site production of cold-spliced fiber plugs for plug-and-play use. It supports single-mode single-fiber transmission, saving fiber usage. The panel-type optical socket transceiver can be powered either by centralized power supply via the power line laid with photoelectric composite cables or by taking power from nearby sources.

It automatically adapts to 10Mbps, 100Mbps, and 1000Mbps environments, facilitating network upgrades.
The device is equipped with 1 built-in 1.25G/SC/1310nm optical port and 2 10/100/1000Mbps electrical ports;
supports full-duplex or half-duplex mode with auto-negotiation capability;
has a store-and-forward buffer to effectively improve the transmission efficiency of termination equipment;
features a built-in store-and-forward mechanism, supports multiple protocols including IEEE 802.3 and IEEE 802.1Q (VLAN);
has a switching capacity of 12G for 2-port and 4-port models, and 20G for 8-port models;
a MAC address table of 8K;
power consumption: ≤3W;
working power supply: DC 12V/1A;
operating temperature: -30℃~70℃;
MTBF: 100,000 hours;
external dimensions: 86mm94mm24mm.

Profile of Zhejiang Jindong Communication Technology Co., Ltd.

Solve the Last Bottleneck of LAN Fiber to the Desktop
——Optical Socket Switch

In-depth Analysis and Era Significance of FTTD All-Optical LAN Solution by Zhejiang Jindong Communication

I. Main Technical Features