Wolfsburg on the way to a smart city

Wolfsburg on the way to a smart city

For the new digital infrastructure, Stadtwerke Wolfsburg and its telecommunications subsidiary Wobcom built a high-availability data center in the heart of the city. Even the IT cabinets there are equipped with several sensors to meet the availability requirements. Central monitoring facilitates maintenance and resource management.

In cooperation with Volkswagen, the city of Wolfsburg has developed a digitization strategy. Wolfsburg wants to become a pioneer in electric mobility. It also plans to create new business areas in the IT sector. 
Stadtwerke Wolfsburg and its subsidiary Wobcom are playing a leading role in the construction of a broadband network and the creation of an open digital platform. Initiatives, offers and projects based on the networking of data from all areas of the city are to be developed on this platform. According to Dr. Frank Kästner, Chairman of the Wolfsburg Public Utility Company, all 80,000 households in the Wolfsburg city area are to be directly supplied with fiber optic by 2021. In addition, a nationwide WLAN is to be created. According to Dalibor Dreznjak, head of corporate development at Wolfsburg's public utilities, this should be available as a public WLAN, but it should also be able to be used for autonomous driving, for example.

The core of the new network

The core of the infrastructure is the Wobcom data center in the Nordkopf-Tower in the center of Wolfsburg. This is the Internet hub for the region with fast connections to other Internet nodes and various networks. The broadband expansion will also create numerous small edge data centers distributed throughout the city. They are needed for fast data processing in 5G mobile phone transmissions and especially for autonomous driving. In addition, the new central data center is connected to another data center of the municipal utilities in the city area.
Wobcom's high-availability data center is located in the Nordkopf-Tower close to Wolfsburg's main train station with a direct connection to the Internet node. 

The new data center serves as the core for the broadband network, hosts regional cloud solutions and offers hosting and colocation services for private individuals, companies and public authorities in the region. It extends over five floors in the core of the Nordkopf Tower. In fact, there are five independent data centers, which allow high redundancy and offer sufficient space for hosting customers.They went into operation in spring 2018 and are Tier 3 and the highest category D according to the Bitkom guidelines for reliable data centers.

Cabinet monitoring increases reliability

In order to achieve maximum system stability, Wobcom Enterprise architect Giovanni Coppa has designed each IT cabinet to be redundant and has the connected components monitored for power consumption via PDUs (Power Distribution Units). He chose Raritan's PX5000 Intelligent Rack PDUs because they provide additional sensor ports to which environmental sensors can be connected. As a result, each cabinet in the North Head Tower now contains two PDUs powered by different circuits. Each cabinet has two combined temperature/humidity sensors connected to them and a door lock with access control. The monitoring of the power consumption enables power-saving operation and a detailed analysis of the consumers in the computer center. This makes it possible to quickly see when which components are causing peak loads. This enables a better and more targeted distribution of hardware in the computer center. 

Current and voltage measurements can also be used to increase availability. In order to detect faults at an early stage, additional measuring points at the input and at the circuit breakers are therefore useful.


Monitoring of temperature and humidity

For active components, the specifications for temperature and humidity must be observed. Therefore the temperature should be measured directly at the server rack. The requirements for relative humidity in the data center are also high and are subject to narrow tolerances. Air that is too dry can lead to electrostatic charging, air that is too humid can lead to corrosion of the installed equipment. 

If possible, the humidity should be measured on the supply air before it passes through the cabinet. Wobcom works with hot and cold aisle enclosures and measures both front and back of the cabinet with combined temperature and humidity sensors. These measuring points can thus be used for climate management based on the recommendations of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). The PowerIQ software supports this evaluation of the climate data.
An administrator can remotely access each PDU connection from his workstation in the Operations Center, control it and read out the measured data. This is done via LAN with the PowerIQ monitoring solution from Sunbird Software. He can also enter upper and lower limit values as well as threshold values for temperature and humidity and define a role-based alarm if these values are exceeded or undercut. For Giovanni Coppa it was important "that the solution is modular throughout and can be easily expanded".

Support for maintenance and troubleshooting

The installed hardware can now be clearly documented and monitored in detail with the monitoring solution. This makes system maintenance easier: the operator can identify malfunctions better and at an early stage.
All devices including sensors are directly connected to the two Raritan PX5000 Intelligent Rack PDUs in the cabinet. Picture: Wobcom
Maintenance work can be carried out during operation. On site, the PDUs with their easy-to-read LCD displays provide a quick overview of the connected components and the associated measured values. Since all devices including the sensors are directly connected to the two PDUs, the cabling remains clear. This also makes maintenance work much easier.

Coppa explains: "The solution exactly meets our requirements and enables us to expand our data center operations to include facility management in an intuitive way. He finds it advantageous that the PDUs have so many sensors and modules and offer a variety of interfaces. The PowerIQ monitoring solution can also be expanded modularly to a comprehensive DCIM solution. "In this way, we can also use the PX5000 PDUs with the sensors outside of the data center and remain compatible throughout". In the medium term, it is planned to equip the other data center with this solution as well. Coppa also plans to install differential air pressure sensors in the cold aisles to monitor the air flow there. This would also ensure that the sensitive components actually receive sufficient cooling.