MOST of German Rail’s (DB) high-speed passengers will come into contact with DB’s new train IT platform ZIP via the revamped ICE portal. The train IT platform is the data hub that provides all ICE passengers with access to free entertainment and a wealth of information about their journey using their browser. An App also provides access to a wide choice of movies.
In addition to these passenger functions, ZIP integrates a separate server for train-specific functions such as providing diagnostic data for predictive train maintenance, and the transfer of status data and failure alerts. ZIP also controls seat reservation and passenger information displays as well as train announcements. Finally, it is used to manage the operation of the bistro, including the cash register, passenger orders and automatic replenishing of food and drink supplies.
Virtualisation makes it possible to consolidate multiple applications separately in a single system. It also enables the addition of new features without hardware and software modifications in order to expand the offer as necessary.
The replacement of the legacy hardware platform on which the passenger portal was previously provided gave DB the opportunity to address past difficulties and completely revamp the IT system on its ICE trains in order to make significant improvements and add new features.
The new platform had to consolidate the hitherto heterogeneous and highly-complex infrastructure for each ICE train into one system. It was also important that this consolidated solution could be integrated into DB’s fleet of 256 ICE trains. This required high performance density in a compact 19-inch system with a 4U form factor and fanless operation. In addition, the new system had to provide sufficient performance headroom to integrate future features without the need for system changes.
The system that is being installed has several terabytes of storage and sufficient computing power to stream video and audio data. At the same time, its flexible design enables it to accommodate additional applications without noticeable losses in performance or quality.
The new IT platform is designed so that only one system is required for all essential functions. DB’s IT platform is controlled by two CPUs, each responsible for dedicated tasks. The Business Service Platform (BSP) is in charge of enterprise applications while the Customer Service Platform (CSP) provides all the functions that passengers can use directly on their devices.
The CompactPCI Serial standard allows the integration of two high-performance CPUs in one system, which can communicate via the backplane. Since the standard also enables a modular configuration, there is no need for any complex, power-hungry cabling that would otherwise be required on the front end.
The individual platform functions of the CSP and BSP are virtualised, which extends the physical separation of the CPUs with additional partitioning on the software side. For example, the ICE portal runs on the same multi-core board as the Maxdome streaming portal, but on a different virtual machine.
This optimises the security and reliability of services; if one virtual system crashes, it does not affect the other. To achieve comparable high-availability with hardware alone would require a matching number of individual CPU boards, leading to unnecessarily high costs and a significant maintenance effort. Virtualisation means that the qualification of functions that are added later is limited to the software. For example, a firewall can be updated regularly without affecting the other virtualised applications.
Before the 19-inch server can be used on trains, it has to undergo thorough testing and requires certification by an independent laboratory according to Railway Standard EN 50155. The certification includes functional testing at extended ambient temperatures ranging from -40 to 85oC to ensure compliance with class Tx, as well as shock and vibration testing. The ZIP server must also meet all interference requirements to prevent interference with other devices on the train.
These challenges were solved by using a modular and maintenance-free 19-inch system based on the modular CompactPCI Serial standard. All cards used support the extended temperature range and are sealed against dust and moisture by a protective lacquer. In addition, all components are soldered.
The individual computing cards can be plugged in and out as required to form functional units that can be swapped at any time during operation. Wireless connections are established via WLAN, UMTS, GSM and GSM-R and combined with the latest Intel processor architecture, Ethernet switches and mass storage media.
I/O interfaces based on field-programmable gate arrays (FPGA) facilitate the adaptation of the system to meet the specific interface requirements of the individual ICE series such as CAN, RS422 or RS485. A dedicated interface card was specially developed for the UIC 568 audio interface used for train announcements.
The almost exclusive use of standard components guaranteed low development costs and meant that the project could be implemented quickly. Thanks to the modular design, the system can also be extended or modified at a later date, while the extreme ruggedness and standardisation of CompactPCI Serial makes upgrades possible.
Another advantage of the modular approach of CompactPCI Serial is the ability to use existing and pre-validated commercial off-the-shelf components to implement complex system designs in the shortest possible time and within a tight budget.
The CompactPCI Serial CPU cards used in the new IT platform are equipped with Intel Xeon D-1500 processors that offer high performance, hardware-based virtualisation functions and are available for at least seven years.
The CPU board provides fast, future-proof I/O interfaces such as 10GB Ethernet, USB 3.0 and PCI Express. A mobile radio connection such as LTE or GSM-R is available for the transmission of diagnostic and passenger data. Positioning is handled by a global navigation satellite system such as GPS, Galileo or Glonass and enables location-based services such as route information and regional advertising. In Europe, it is possible to combine the data from GPS and Glonass for even more accurate positioning.
The CSP can be equipped with up to four 2.5-inch SSDs and the BSP with up to two SSDs, each with a capacity of 1TB. A small display in the front panel shows the diagnostic status of the CPU and the installed modules, as well as maintenance instructions. In compliance with railway standards, it does not require fans and supports the prescribed temperature range despite having two multi-core processors. The system is protected against unauthorised external access by a sheet of Plexiglas secured with an electromechanical lock.