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Securing Munich Airport

Since Munich International Airport (Germany) opened in 1992, the massive increase in traffic has pushed it much sooner than expected to the limits of its capacity. Several years ago, Flughafen München started the project for a new terminal building.

In the summer of 1999, preliminary work began for Terminal 2. The new 260 000 m² terminal building will double the airport's capacity with room for 20-25 million additional passengers per year. Terminal 2 has been fully operational since summer 2003. Some other figures: construction cost 1,3 billion Euro, 114 gates, 77 aircraft park positions.

Customer requirements

Looking for a high-performance fibre-optic video transmission system, Munich Airport was particularly impressed by the OTN's system capacity, high reliability, flexible integration of other peripheral CCTV equipment and a simple-to-use 'video management system' (VMS) integration.

The initial tender favoured an ATM-based network however, and Gb Ethernet was also considered.

A visit to a reference customer (Metro of Bonn) convinced Munich Airport that the OTN performance would definitively meet its requirements.

OTN's proven track record, price/performance ratio and impressive reference list all contributed to Munich Airport's final choice for the OTN.

Network architecture

Today's growing interest for digital video systems with fibre-optic transmission and Ethernet transmission systems results automatically in a higher demand for system capacity. Mainly for this reason, the OTN family has been reinforced with a new member providing up to 2,5 Gbps system bandwidth: OTN-2500.

The distribution of operator workstations (keyboards, monitors) around the airport terminal and the large number of cameras favours a network-based approach, since all video signals are available anywhere and since network nodes can be placed closer to the cameras, thus reducing cabling.

The classical CCTV approach applies a network of matrices, interconnected by point-to-point optical or coax cabling and is by concept very focused on centralised control: one central control room with optionally local control rooms, which are limited in scope to their own local cameras.

But there is a tendency for multiple control centres: every airport authority requires its own CCTV control for different purposes: passenger security, parking lot surveillance, operations control, fire surveillance (enhanced with video surveillance)...

The Munich Airport Terminal 2 illustrates this with its 102 operator workstations spread around the premises.

In addition these control centres independently need access to any camera around, not just to their own fixed set of cameras. If an operator must be constrained, this must be done by software configuration, not by network architecture.

Also, a network-based approach allows for reliable video transmission and for the flexibility to expand or modify the CCTV application without interruption of service: add cameras, add or move control centres...

And finally, broadcast image quality and low latency (ie low video image transmission delay) are mandatory requirements for professional CCTV surveillance applications, in order to be able to adequately recognise people and incidents and to do fast video switching (eg in sequences) and accurate PTZ control. These strong points in traditional analog CCTV tend to be overlooked by the emerging IP-based CCTV systems.

In short, the OTN video switching service controlled by the OTN video solution (OVS) software can be seen as a large, reliable distributed CCTV matrix for broadcast quality video with low latency. It incorporates the best of both the traditional analog CCTV systems and the digital CCTV network-based systems.

The OTN-2500 network for Munich Airport Terminal 2 consists of 101 N215 nodes located at 15 different buildings.

Clear observation and accurate monitoring of Munich Airport Terminal 2 is obtained by connecting up to 506 fixed and 244 PTZ cameras, 176 monitors and 10 VCRs and 102 operator consoles to the OTN-2500.

Offering full video matrix switching capability, the OTN-2500 directed by the interactive video management (IVM NT) system - the Siemens Building Technologies (SBT) VMS - can be programmed to display the image from any camera on any monitor, either manually or via independent automatic switching sequences.

The IVM NT is the controlling 'heart' of the CCTV services. It allows for operation, visualisation, parameterisation and control of all video components, including cameras, video motion detectors and digital recorders. It has a server/client architecture and comes as a multi-user system.

Due to the size of the installation and the fact that it is vital for the airport terminal operations, the IVM NT server is configured as a redundant server.

The IVM NT allows for a mixture of CCTV keyboards and graphical operator workstations.

The IVM clients are connected through the OTN to the central IVM server.

Clients can be either PC-based workstation consoles with graphical user interface or PCs supporting multiple CCTV keyboard consoles.

The on-site receiver/drivers support operator control of pan, tilt, zoom, focus and iris (PTZ) and multiple presets; these PTZ signals are transmitted through the OTN. In addition remote parameterisation of the cameras from the central control room is supported.

Distributed alarm inputs and outputs (I/O) are used to automatically activate any camera or group of cameras (salvo) to be displayed. For this purpose, lowcost PLCs are used as digital I/O modules, and they are connected to the IVM NT servers via the OTN network.

IVM NT offers a choice of alarm handling scenarios for handling multiple simultaneous alarms: alarm queuing and acknowledgement by GUI operators, alarm monitor dispatching (if the first alarm monitor is occupied, then automatically select the next one...).

An additional project requirement was to be able to select and control cameras from the existing Terminal 1 installation: the existing older Siemens SBT matrices are maintained in Terminal 1 (over 1000 cameras), but a number of video trunks interconnect them to the Terminal 2 OTN network and IVM NT will be extended to incorporate camera selection and control to these matrices.

Implementation details

Video

Video VID4-IN-X interface cards are provided to connect the cameras, video VID4-OUT-X interface cards to connect the monitors and digital recorders to the OTN. M-JPEG compression is used by these cards, which offers broadcast resolution (PAL 704 x 576 as applied in this project; 704 x 480 in case NTSC would apply), realtime images (50 fields/sec for PAL, 60 fields/sec for NTSC) and very low latency (ca. 80 ms).

IVM NT Client/Server configuration, PTZ control, distributed alarm I/O

All three applications require Ethernet LAN connectivity. Therefore, Fast Ethernet ET-100 interface cards are provided to set up one physical Ethernet across the OTN network.

PTZ control is usually implemented on OTN with a full duplex RS422 bus: the video management system is the bus master and in every camera location an RS422 slave port is dropped off to a daisy chain of camera PTZ receiver/drivers. However, in this project the redundant IVM NT server configuration required two masters, which is not feasible with RS422; therefore the Ethernet service is used and in the camera nodes an Ethernet COM port server supports the daisy chain of TTY (20 mA current loop) telemetry which Siemens applies for its PTZ receiver/drivers.

In addition to PTZ control, the fixed cameras have a telemetry interface to allow the central CCTV administrator to remotely set or modify the camera parameters.

The CCTV keyboards are attached to an IVM NT client PC, which is then interconnected through the Fast Ethernet service to the central IVM NT server pair. This client PC supports keyboard emulation. Other operators have an IVM NT client PC with a graphical user interface, which is equally connected to the central IVM NT server pair.

The distributed I/O units are Siemens Simatic S7 200 PLCs, which provide a point-to-point serial link to a management system.

Because of the large number of PLCs and because the management system is a redundant pair of server PCs, again the same Fast Ethernet service is used, which connects the remote client PCs to the IVM NT server PCs. On these PCs an Ethernet COM port server application runs to connect the PLC's point-to-point link.

OVS

The OTN OVS software runs on the same PC as the IVM NT server. Both are interconnected through an IP socket interface (ie a software API).

OVS provides video switching, PTZ control and screen titling (on-screen display). It converts the Simatrix host protocol from the IVM NT server to the SCU protocol for PTZ control towards the camera receivers; the latter includes remote camera parameterisation for both fixed and PTZable cameras.

The screen titling abilities have been expanded:

* Camera titles can still be pre-configured, but as an alternative they can also be sent by the IVM NT when making a video connection.

* IVM NT can also send alarm titles to any video output.

* The title format is enhanced: colour, background colour, flashing, ...

* Title position can be anywhere on the video screen, 25 characters per line and 14 lines.

* Time and date can be displayed in any position as well and in different formats; OVS periodically updates time and date on all video cards.

* Automatically a Video Loss title can be displayed upon loss of video signal sync at a video input.

So in short, OVS presents OTN as a Simatrix to the IVM NT, talking the same protocol.

IVM NT/OVS redundancy

IVM NT is equipped in a redundant configuration: two server PCs with IVM server software and with OVS, interconnected with a dedicated Ethernet link. It is automatically decided between both server PCs which one is active and which is hot standby; this depends on the software components being operational and if the OVS has access to the OTN master video card and to the OTN internal OVSCom control channel. The system database is permanently replicated between both servers through this dedicated Ethernet link.

Project planning

Siemens was awarded the contract in September 2001. The functional approval test was performed with success in February 2002.

The complete installation has been in service since the start of Terminal 2 operations in mid-2003.

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