A metropolitan area network without compromise

Poznań. On the one hand, one of the oldest cities in Poland. On the other hand – a modern metropolis inhabited by more than half a million of people and a true industrial, commerce, logistics and tourism hub in west-central Poland. It is not by coincidence that the capital of the Greater Poland region has topped the national rankings in the categories of education, healthcare, quality of living, and public security. The latter can be credited to the work of the Crisis Management and Security Department (CMSD) within the City Hall.

“We plan, organize and coordinate actions in regards to crisis management, non-military defense, flood response strategies, as well as fire and civil defense”, says Michał Lemański, Deputy Director of Security at the CMSD. “Our job is to prevent extraordinary threats to the life and health of residents and the environment. We take care of the public order and safety, as well as maintaining, administrating and modernizing the technical security systems”.

Working in the Crisis Management and Security Department is no picnic, as it means a whole lot of responsibility. Especially when you’re provisioning a number of public institutions, as well as both local and federal government agencies – from the City Roads Authority and City Transportation Office to Provincial Police Headquarters in Poznań, National Fire Service, Main Inspectorate Of Road Transport or the CMSD’s equivalent operating at the voivodeship level.

Being an operator of a multi-service metropolitan network, spanning more than 300 kilometers of optical fiber, CMSD supports the functioning of some the key public services, such as traffic light controllers, surveillance cameras, traffic modelling sensors or the Intelligent Transportation Systems (ITS), including variable message signs (VMS) for drivers and passenger information systems at the public transportation stops. CMSD’s resources are also utilized by the Poznań Electronic Agglomeration Card (PEKA), Poznań’s smart city card.

As one can easily guess, the top priority for organizations such as the Crisis Management and Security Department in Poznań is the stability and reliability of their network. The fact that the last modernization of the CMSD’s networking infrastructure took place in 2010 was slowly taking its toll – the first symptoms of obsolescence began to pose an actual threat to the operational continuity of the provided services.

“In the past few years, we had to deal with a couple of failures of the aggregation layer devices, as well as single modules of the backbone devices, mainly power supplies on the switches. Every network disruption can potentially compromise the safety of the city and its residents, therefore it was a clear sign for us: it’s time to act”, explains Anna Frankowska, Technical Security Systems Manager at CMSD. “However, we faced a difficult challenge. On the one hand, the backbone devices were no longer supported by the vendor due to the end of their production cycle. On the other hand – the access layer devices, connected in the star topology, were completely non resilient to the failure of the backbone nodes”.

The importance and scale of the challenge meant that there was no room for compromise and cutting corners for the Crisis Management and Security Department in Poznań. That is why Integrale IT, an Extreme Networks Diamond Partner, was brought on board.

“When designing the new network for the City Hall in Poznań, our priority was to maximize the reliability of the proposed solution. We wanted to completely eliminate and break free from the single points of failure while ensuring the continuity of the provided services”, says Łukasz Pękal, Technical Director at Integrale IT. “Thanks to the use of dense wavelength-division multiplexing (DWDM) technology, which multiplexes a number of optical carrier signals onto a single optical fiber, every single access node has gained links to two backbone nodes. It was fundamental to base the new network on Extreme Fabric Connect, the flagship solution from Extreme Networks”.

“The solution allows network professionals to build a fully resilient, multi-service network”, adds Piotr Szołkowski, Pre-Sales Support Engineer CEE at Extreme Networks. “What it means in practice is that the potential failure of single fiber connections does not impact the availability of services, as the latter are automatically rerouted through the shortest-path to other devices in the fabric network”.

The story of CMSD’s network modernization is not merely about hardware refresh. Maintaining the continuity of services during the migration phase was a particularly difficult task, especially given the size and complexity of the environment – after all, we’re talking about more than a hundred nodes spread across the entire city of Poznań. As everybody knows, a scheduled downtime can be considered a paradox by its sheer definition – we have covered that topic in more detail in this blog entry. However, for Integrale IT, there is no mission impossible.

”We worked under some heavy time constraints to minimize the downtime as much as it was physically possible. For example, in order to deploy 36 services, we needed to complete 160 cable crossing across the entire city”, recalls Piotr Krótki, Senior Network/Security Engineer at Integrale IT. “The migration process itself was very well planned and prepared, and that’s why we managed to limit the service unavailability window to an absolute minimum”.

They say every rose has its thorns. More often than not, the reliability of a network can be increased at the cost of growing complexity of configurations and adding new services. For metropolitan area networks like the one in Poznań, the closed-circuit television plays a critical role in ensuring public safety. Usually, the system requires multiple operators to able to access single cameras which, in case of the previous networking infrastructure, was simply not possible.

”Limitations of multicast routing in the network backbone proved to be a huge disadvantage of the previous solution. Given the rapidly-growing number of security cameras, it really started to impact the functioning of the city’s Closed Circuit Television Surveillance System”, recalls Anna Frankowska.

The Extreme Fabric Connect solution used by the Crisis Management and Security Department in Poznań supports the functioning of intelligent monitoring systems. Elimination of complex protocols enabled scalable IP multicast deployment of up to 1156 cameras. Provisioning is required on only the ports attached to cameras and monitoring stations/and receivers – with no need to provision any core switches in between.

This not only reduces the risk of an outage due to human error during change but also allows the video surveillance network to be deployed faster and easier than ever before – with the ability to add, move and change cameras on the fly. Once the end points are provisioned, the network determines the shortest path from the sources (the cameras) to the destinations (monitoring stations) with optimized network path delivery, thus improving video delivery performance over traditional networked-based solution.

“By eliminating traditional PIM layered protocol stacks and replacing them with a simplified ISIS routing / IGMP snooping combination, the used solution is simple to implement and operate, less error prone and fast to converge, should adverse network conditions occur”, explains Piotr Szołkowski. “Thanks to Extreme Fabric Connect solution, the Crisis Management and Security Department in Poznań can enjoy an optimum blend of network reliability, efficiency and ease of use”.

Today, the city of Poznań can be considered a brand of its own. That’s evidenced, among other things, by its inclusion in the list of Globalization and World Cities think tank which is categorizing world cities into "Alpha", "Beta" and "Gamma" tiers, based upon their international connectedness. The boundary conditions that need to be met by the candidate cities, include a well-developed transport infrastructure, as well as an elaborate telecommunications network. The latest investment of the City Hall in Poznań is a major step forward in both aspects.

“It was a really big challenge for all of us, both in terms of technical issues and logistics. That being said, together with the Integrale IT team, we have done an amazing work, following the plan to the letter and within a set timeframe. I can wholeheartedly say that today we are the owners of a modern, automated and even more reliable network which enables us to provision services for our customers on an even higher level of quality”, says Jarosław Androsiuk, ICT Maintenance and Administration Specialist at CMSD.

The support service of the management of the new network infrastructure is an added value for the Crisis Management and Security Department.

“Both the service and administration is being handled with the guaranteed support from the Integrale IT team. We can count on their support twenty-four hours a day”, Jarosław Androsiuk sums up.

The Integrale IT team consists of experts with many years of experience. The mission of the company is to deliver comprehensive and innovative networking solutions to enable the digital transformation of companies and organizations. To that end, IT Integrale offers the following range of services:

Integrale IT has three offices in Poland: in Gdańsk, Warsaw and Cracow, coupled with a robust service partner network.