PENS is based on the idea of sharing content and information. All PENS users located at the same site can in fact share the same infrastructure in a secure way, providing substantial economies of scale. PENS provides a secure and robust infrastructure for exchanging information between the users connected to it, since the pan-European network offers fully redundant connectivity.

It will enable its users to exchange critical and common aeronautical information in a seamless and integrated manner, providing a highly cost-effective common infrastructure for the deployment of emerging ATM applications. It will significantly reduce the costly fragmented network services implemented under the umbrella of the outdated X.25 protocol, still in widespread use by some ANSPs.

PENS will be one of the main enablers for the Collaborative Decision Making (CDM) concept that is being developed in the context of SESAR. It will meet both current needs for the information exchange between air service navigation providers (ANSPs) and ATM stakeholders, as well as those forseen by the SESAR Programme for the System-Wide Information Management (SWIM) initiative.

EUROCONTROL and the ANSPs are working together on the PENS project, improving it in order to turn it into one of the key elements in the future technical infrastructure of ATM in Europe. PENS mean significant cost savings and the optimisation for the ATM community in Europe.

The PENS project was initiated jointly by EUROCONTROL, certain ANSPs (Aena in Spain, NAVIAIR in Denmark and LFV in Sweden) and SITA on 28 October 2009. All EAD clients who decide to connect to EAD through PENS will be supported in their migration activities. Initial services started in mid-2010.

Since then, the number of PENS users has been increasing constantly and a high growth rate is expected in the future. Negotiations are planned in order to open up the PENS community to airlines, airports, the military, future aeronautical applications (RIMS, MCC, SATCOM), and other ANSPs which currently do not belong to PENS, as well as other ATM partners with similar communications needs.

Who is already a PENS user?

Since the signature of the contract on 28 October 2009 between EUROCONTROL and SITA for the provision of PENS, the following organisations have become PENS users:

• EUROCONTROL for CFMU and EAD services
• Aena, Spain
• NAVAIR, Denmark
• LFV, Sweden
• LPS, Slovakia
• Finavia, Finland
• Avinor, Norway
• NAV, Portugal
• Hungarocontrol, Hungary
• ENAV, Italy
• Croatia control
• Slovenia control
• NATS, United Kingdom
• DFS, Germany
• DSNA, France
• Skyguide, Switzerland
• Austrocontrol, Austria

Whilst IAA (Ireland) has stated its willingness to join by signing a Letter of Intent, BULATSA (Bulgaria) and ROMATSA (Romania) have signed the Common Procurement Agreement, which is the first step in the application process.

Other ANSPs have signed the Common Procurement Agreement, but have not yet started the finalisation of the accession process:

• BULATSA, Bulgaria
• ROMATSA, Romania
• PANSA, Poland

In addition, EUROCONTROL is about to include a dedicated infrastructure for the SESAR validation activities, thus further expanding the scope of PENS.

Benefits of joining PENS

According to EUROCONTROL and its Member States’ ANSPs feasibility studies, the establishment of a single pan-European network service would:

• provide more cost effective than fragmented network services;
• meet current and future communication needs;
• achieve flexibility and speed of deployment by providing a managed international IP (Internet Protocol) service environment;
• provide greater capability for integrated developments involving the whole ATM community by enabling a rapid and secure exchange of information;
• align with Single European Sky implementing rules and industry standard services by supporting IP-based networking.

PENS governance bodies:

• The PEN Service Steering Group (PSSG), represents the PENS users, and sets the policy, standards and review performance.
• The PENS User Group (PUG), consisting of members from the user community, provides technical, financial and administrative advice to the PSSG.
• The PENS Management Unit (PMU), implements the policy and standards set by the PSSG and manages the PEN Service.

The Network Service Provider (SITA)  provides an IP managed network and a helpdesk that is accessible to all PENS users.

Virtual private networks available on PENS

Several virtual private networks (VPNs) are available on PENS:

1. An ANSP VPN is composed of:

• Test VPN
• Operational VPN
• SESAR VPN

1. An EAD VPN
2. A CFMU VPN

All VPNs are independent for security reasons. See the illustrations below for technical details of each VPN.

A PENS node is basically a dual router interface (ANSP BB) to the “user LAN”. Each PENS user can then directly interface its own LAN. PENS supports both IPv4 and IPv6 protocols, unicast and multicast.

Quality of services provided by PENS

PENS can provide different quality of services, depending of the users requirements:

• IPVPNs with Gold Class of Service (three levels of priority)
• Dual stack IPv4 / IPv6
• IPv4 addresses are provided by PMU/SITA
• IPv6 addresses are provided by EUROCONTROL (based on the iPAX Task Force)
• Tight SLA with SITA for the service including:
   - 24/7 Dedicated PENS Service Desk
   - 99,99% availability
   - Certificate of physical diversity of the circuits
   - Quarterly audit of Single Points of Failures (layer 1/2/3)
   - Remote monitoring access for ANSPs
   - Monthly reporting.

Technical details of each VPN

How to become a PENS user?

There are several steps to follow in order to become a PENS user:

• An organisation interested in becoming a PENS user has to declare its intention and interest by signing the Common Procurement Agreement (CPA), which allows EUROCONTROL to act on behalf of each signatory in the selection of the national service provider, the negotiation and signature of the PENS contract and the subsequent management of the contractual relationship with the national service provider.
• The signature of the CPA does not mean the organisation becomes a PENS user. After the signature of the CPA, it has to submit its application to the PSSG.
• If it is accepted, the PSSG informs the PMU who has to negotiate an amendment to the PENS contract in order to expand the service to the candidate PENS user, who previously will have signed a letter of consent allowing EUROCONTROL to act on its behalf.
• Finally, the candidate officially becomes a PENS user.

Each PENS user has to pay a charge for the service required in accordance with the “Charging for the PENS” document.