By Zhu Hong
Since innovative copper technologies such as Vectoring and G.fast continuously evolve and legacy copper usage accelerates both network deployment and service provisioning, more and more carriers are deploying the copper-based fiber to the cabinet (FTTC) outdoor cabinet solution for ultra-broadband network.
Installation and maintenance requirements of outdoor cabinets
As innovative copper technologies such as Vectoring and G.fast mature and legacy copper accelerates network deployment and service provisioning, more and more carriers are applying the copper-based fiber to the cabinet (FTTC) solution. The installation and maintenance of outdoor cabinets differs significantly from the exchange-based operation model. Additionally, outdoor cabinets are subject to extreme temperatures, dusts, floods, and external damage. Sealed design and environment surveillance are required so that abnormalities will be detected and corrected, ensuring stable and reliable operation. The system should have smart automatic main distributing frame (AMDF) jumpers and be scalable so that no manual work is needed in service cutover. When the number of users increases and expansion is required, modular expansion can quickly boost the capacity of outdoor cabinets so there is no need to migrate or replace the entire cabinet or components.
Huawei's FTTC solution offers one-stop E2E products and solutions to simplify site deployment, including network devices, cabinets, power supplies, batteries, cable distributors, as well as remote surveillance management. Huawei's outdoor FTTC cabinet solution has seen large scale deployment by BT, eircom, and Telkom South Africa. The solution helped carriers reuse existing copper wire resources and deliver ultra-broadband coverage.
Design and environment testing
Many carriers place strict requirements on outdoor cabinets to ensure the products can survive harsh open environments. With powerful R&D teams and high-reliability design, Huawei can deliver highly resilient cabinets. For example, some outdoor cabinets have stainless shells in order to withstand hurricane winds and other external threats. No riveting points can be detected from outside, which means they cannot be drilled open. The cabinet can survive 80mph automobile impacts with barely a scratch. The shell components of the cabinet can be replaced onsite without service interruption. The cabinet is rated IP55 for water and dust protection. A variety of temperature, humidity, smoke, and entrance guard sensors are installed in the cabinet, allowing engineers to remotely monitor the cabinet interior. Batteries can also be charged or discharged remotely. In case of power failure, the cabinet system switches to the backup battery and issues an alarm to ensure operation stability.
Huawei ensures the robust character of cabinets through E2E environmental conditions testing. Huawei has a number of internationally certified environment testing labs that expose cabinets to hellish conditions including temperature extremes, dust, smoke, radiation, electromagnetism, noise, as well as earthquake and security simulations that test cabinets’ ability to withstand physical assault. Testing discovers any weaknesses in a system, which is then improved and optimized to ensure reliable operation of the cabinet and protection of the devices inside.
Cabinet innovation
As user demand for bandwidth increases, more and more users are shifting to FTTC ultra-broadband services. Increasingly, outdoor FTTC sites are being deployed and the number of device ports is increasing as well. Outdoor cabinets need to be flexible and scalable. Therefore, Huawei developed modular cabinets, which are designed to be expanded whenever needed by simply attaching additional device compartments, cable distribution compartments, or power and battery compartments. The cabinets also support the upgrade of the heat dissipation system and smooth cabinet expansion and upgrade through the flexible combination of modules.
Ultra-broadband deployment is reaching many remote and rural regions. There is a strong demand for cabinets of higher capacity and lower cost. Huawei designed two new cabinet types based on traditional main distribution frame (MDF) cabinets. One type is the "re-shell cabinet," By removing the shell of an MDF cabinet (the original MDF and cables remain) and adding new active devices into it, you have a re-shell cabinet. The main benefit of the re-shell cabinet is that customers can reuse the original MDF cabinet site, saving construction costs. However, re-shell cabinets require that the original MDF cabinets are of the same specifications and low capacity. Additionally, the original MDF and cables must be good enough to be reused. Britain is one place that Huawei's re-shell cabinets are seeing large scale deployment for rural broadband construction.
Huawei has also introduced the "top-box cabinet," which replaces the cap of an original MDF cabinet with an active device compartment. Active devices are placed in the compartment to support ultra-broadband networks. Top-box cabinets have strict requirements on the uniformity of the original MDF cabinets. The cap of the MDF cabinet should be removable so that hardware merger can be done. For example, eircom deployed top-box cabinets in its ultra-broadband construction in remote areas.
Many cabinets are installed on city streets, where they become part of the city scenery. Therefore, Huawei has developed special outdoor cabinets to which LCD screens can be attached for advertising. Carriers can remotely update or turn off the screens. Carriers can further use the outdoor cabinets to expand into new services. For example, they can transform the cabinets into automobile charging centers or Wi-Fi hotspots.
The advantage of outdoor FTTC sites
With legacy copper ultra-broadband construction in full swing, network devices are being moved from exchanges to outdoor FTTC sites. Sites are playing an increasingly important role in networks. They act as ultra-broadband acceleration centers, remote power supply and backhaul centers, as well as comprehensive management centers.
Broadband acceleration center: Copper wires in the outdoor FTTC sites are very close to users. Using VDSL2 and Vectoring, 50M to 100M access rates can be achieved. Since the sites reuse original MDF cabinets and cables, the ports are concentrated and the system capacity is large. Compared with other ultra-broadband construction models such as FTTH, fiber to the building (FTTB), or fiber to the door (FTTD), outdoor cabinets prove more economical and efficient, minimizing construction cost per user. As innovative copper access technologies continue to emerge, network speed can be further accelerated by replacing service cards while the site and cabinets remain unchanged. If there are multiple pairs of cables on the users' side, multi-pair bonding can also be used to improve the access rate.
Power supply center: An FTTC site has an AC power supply and batteries for backup. In addition to the cabinet itself, the power supply system can power Wi-Fi hotspots, remote FTTB and FTTD devices, and devices in LTE small-cell base stations. The site can provide various types of power supply through multiple pairs of telephone lines. FTTC sites also support E2E power supply management.
Backhaul center: In addition to power supply, FTTC sites can provide uplink backhaul for surrounding Wi-Fi hotspots, FTTB/FTTD devices, and LTE small-cell base stations. Optical fiber can be used to achieve uplink aggregation and multi-pair bonding of copper wires can be used to provide uplink interfaces to remote devices, which is very suitable for broadband coverage in remote rural areas.
Management center: FTTC sites achieve sound management of site devices, power supplies, batteries, cabinet temperature/humidity, and security. Remote battery charging/de-charging is also supported. FTTC sites also help to manage aggregation channels for surrounding Wi-Fi hotspots, FTTB/FTTD devices, and LTE small-cell base stations. Smart FTTC sites can also be integrated with automatic MDF (AMDF) to facilitate automatic management of service cutover, such as cross-connection of external ports and internal devices. Automatic jumper operation can be performed remotely, which eliminates operation errors and minimizes connection management errors as well as maintenance costs.
One-stop delivery
Building copper-based ultra-broadband networks will inevitably involve outdoor sites and devices. If integration is conducted at sites, conditions such as bad weather and challenging environments can complicate and delay delivery progress, compromising project quality. Huawei's one-stop delivery solution successfully integrates all cabinets, devices, power supplies, batteries and MDFs while they are still at headquarters.
The service functions of all ports are also tested to ensure successful integration. In this way, integrated equipment arrives on site ready for rapid and high-quality delivery. Going forward, the one-stop delivery solution will undoubtedly become a popular option for carriers utilizing legacy copper in their ultra-broadband deployments.
As a leader in the access network industry, Huawei’s broadband network devices have served over one-third of the world's population. Huawei's outdoor cabinets can be found in every extreme environment the earth has to offer, from rural frontiers to densely populated urban centers. Huawei is dedicated to helping carriers deploy networks that are faster and smarter.
