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Page 1: Railway Internet

Broadband on trains

Generic description

Page 2: Railway Internet

Solution description

Table of contents

1. INTRODUCTION................................................................................................................................3

2. THE ONBOARD ARCHITECTURE.................................................................................................4

2.1 THE MAIN SERVER – CG6400........................................................................................................42.1.1 Technical data - hardware........................................................................................................52.1.2 Functional description of onboard software.............................................................................6

2.2 ROOF TOP ANTENNA.....................................................................................................................102.3 THE SECONDARY RACK: WDS200...............................................................................................11

2.3.1 Technical data.........................................................................................................................122.3.2 Features...................................................................................................................................13

2.4 OPTIONAL: CERTIFICATION OF MAIN EQUIPMENT........................................................................142.5 ON TRAIN TV SCREENS................................................................................................................15

3. SERVICES PROPOSAL...................................................................................................................17

3.1 SUPPORT MODEL..........................................................................................................................17

4. Abbreviations........................................................................................................................................18

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Solution description

1. Introduction

Nokia Siemens Networks is the global market leader in railways solutions, covering a full range of railways solutions and applications such as GSM-R, Broadband on trains infotainment on trains and many more railway applications.

With the Broadband on trains solution Nokia Siemens Networks provides a complete end to end solution with services such as equipment delivery installation, maintenance, operations, marketing and end to end project management.

Our proven BBot (Broadband on trains) solution is based on a Modular System with Open Architecture and Standard Interfaces and Protocols to satisfy specific railway operator’s need for further extension of various additional services for passengers and/or train staff.

The technical solution comprises three building blocks on train infrastructure, a ground to train communication system and an on-land network operation centre. All on train infrastructure is designed to meet with international train regulations. Our proven solution provides a reliable, continuous service supported by all available backhaul solutions.

Figure 1: Generic BB on Trains architecture

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Solution description

2. The onboard architecture

2.1 The main server – CG6400The CG 6400 is the central broadband communication platform containing all main features and functions. The unit acts as a communication gateway between the onboard applications and the centralized on land equipment.

In order to maximize data bandwidth and improve the overall ground to train connectivity, multiple data backhauls are managed simultaneously via the mobile access router (MAR) located in the CG 6400. The CG6400 comes in a railway compliant standard configuration (3U, 19inch). The standard unit is future proof and can be easily expanded with additional applications and network cards. The CG 6400 unit can be easily connected with outside rooftop antennas supporting mobile networks working in a wide range of frequency bands.

Figure 2: CG6400 Standard configuration

Figure 3: CG6400 project specific design

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Solution description

2.1.1 Technical data - hardware

The CG6400 may consist following railway compliant hardware:

A AC/DC 110V power supply. It is assumed that for connection of the power (110Volt DC) connectors are delivered by the customer. For the main rack a Harting connector nr 09 06 215 2871 + H15 shell housing need to be provided.

A CPCI frame with one backplane. One 3 U Compact PCI Celeron M722 processor unit with 2GB RAM and 2GB CF

memory for running the MAR software Two 3U carrier boards each can carry two mini PCI-X modem modules. One mini-PCI-X WLAN (802.11a,b,g,draft-n) 3 mini-PCI-X 2G/3G/LTE modem modules, each supporting:

o GPRS: GPRS / EDGE Multi-slot Class 12 (4 slots Rx, 4 slots Tx) GPRS CS1-CS4; EDGE MCS1-MCS9

o EDGE: 850 / 900 / 1800 / 1900 MHz GPRS / EDGE Multislot Class 12 (4 slots Rx, 4 slots Tx) GPRS CS1-CS4; EDGE MCS1-MCS9

o HSUPA / HSDPA / UMTS: Multi-bands variants with RX diversity 850 / 1900 / 2100 MHz Power Class 3 (+24 dBm) HSUPA mode: 2 Mbps: category 5, (upgradeable to 5.76Mbps:

Category 6) HSDPA modes:

HSDPA 1.8: Categories 1-4, 11 and 12 HSDPA 3.6: Categories 5 and 6 HSDPA 7.2: Category 7 and 8

Equalization and Rx Diversity at the same time UMTS: 384 Kbps operation in downlink, 384 Kbps in uplink

o LTE 1800 GPS unit installed in the CG6400 unit, and connects to the MAR, which

distributes the information for further usage. o The GPS receiver connects to an active antenna on the rooftop of the

train. o LNA power supply: 5VDC / 50mA o The GPS modem tracks 20 satellites simultaneouslyo The GPS information is distributed in NMEA-0183 format. The following

info, among others, is available: GPS location Speed of the vehicle Height of the vehicle UTC time Number of satellites in view

Free and spare slots are covered by front panels, shielded with EMC gaskets

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Solution description

Dimensions 3U ( 135mm) x 19 inch; depth = 291 mm

Weight +- 15 kg

Operating system Linux

Power supply 9 … 154V DC (in 3 selected ranges)

Power consumption 35 watt on 9 … 154 VDC without options

Temperature ranges (operating)All cPCI boards are from -40 to +85°C at an

airflow of 10m³ / h

Relative humidityAll cPCI board are resin coated and support

up to 95% RH non-condensing

Figure 4: Technical specifications CG6400

2.1.2 Functional description of onboard software

Following software modules are integrated in the CG6400 unit.

2.1.2.1 The Mobile Access Router (MAR)The mobile access router software is responsible for setting up and maintaining the data connections between train and ground. To avoid connections to be lost when the backhaul link is switched (e.g. from a cellular link to a WiFi link), the mobile router encapsulates all data traffic into IP tunnels. These IP tunnels are terminated at the on-land tunnel server (TS), thus ensuring a seamless switchover from one backhaul technology to another.

MAR Features:

1) Routing algorithms: the way the MAR uses the backhaul networks

Priority switching: a link with a higher priority is always preferred over others, when available;

Link quality switching: if a link drops below a configurable quality level, a switchover to another link is made;

Location based routing: links are used or abandoned based upon GPS coordinates (location);

Link aggregation or bundling: two or more links are aggregated in one bit-pipe;

VLAN transparent routing: a VLAN on the train is transparently routed to a VLAN on the tunnel server;

QoS: priority routing based upon VLAN tag, protocol/port number; Any combination of the above, allowing for e.g. least cost routing.

2) Security

Local dynamic firewall, able to work with changing IP addresses on links; Probe packets between MAR and TS protected by ICV to prevent man-in-the-

middle attacks; Router software daemons run as a normal user and uses sudo when root

privileges are needed; Management traffic flows between MAR & TS in an IPsec protected tunnel.

3) Quality of Service (QoS)

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Solution description

There are 3 levels to be considered regarding QoS:

On the onboard network. This network is not part of the estimate, but is based upon Bombardier sourced equipment. The Broadband on Trains WLAN access points support Virtual Access Points (VAP). We assume that VLAN QoS management will be supported on the onboard Ethernet network, enabling each VAP to connect to a VLAN on the train backbone network. Each VLAN can be assigned to a priority level to support QoS management.

The mobile router can treat incoming packets according to several priority levels. A packet is assigned to a priority queue by the MAR according to the VLAN it is using, or the TCP/UDP port number, or according the TOS/DSCP byte.

The radio connections, on the other hand, have different characteristics: o For the WiFi connections in the railway stations and depots, bandwidth

can be reserved and QoS levels managed by the in-station network.o For a 3G public network provider, it is theoretically technically possible to

do this, but almost no mobile network operator (MNO) currently offers this. The solution is dependent on what the backhaul network providers can offer us to support E2E quality of service.

4) Fair bandwidth management

The purpose of fair bandwidth management is to divide the available bandwidth in a fair manner to all users or applications that want or need to make use of it. This is only needed when the total available bandwidth required is less than what is available.

5) Management & provisioning

SNMP stack and MIB for alarming and statistics; SMP: Smart Management Proxy interfaces with the management server on-land

using SNMP, has the ability to interface with non-SNMP enabled network elements onboard of the train, and remotely execute scripts on network elements. The SMP has a built-in file upload/download mechanism, which allows for firmware, software, content, etc to be transferred between train & ground. The SMP has the ability to make partial transfers of large files, and to resume after interrupted transfers. The amount of throughput that SMP can maximally use for these transfers is configurable, to allow a fair amount of throughput for other users or applications.

Configuration via up-loadable configuration file; Configuration & diagnostics possible local via RS-232 port or remote via SSH

access over the network; This interface is used:

to diagnose the system

to configure the system

to update new packages

to install customized scripts

to test the system

to check the backhaul link status and quality

to view log files and save them if needed The local configuration and diagnostics interface main menu is shown below.

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Solution description

Figure 5: The Mobile Access Router management tool

2.1.2.2 The Performance Enhancement Proxy (PEP)In contrast to the classic TCP accelerators, commonly used on satellite connections and WAN connections in general, the PEP is specifically designed to work in conditions which are typical for a train to ground communication system, where the characteristics of the links change very dynamically. In particular bit errors resulting in packet loss, and considerable variations in throughput and packet delays (jitter) cannot be properly handled by the traditional WAN accelerators.

The main actions that the PEP performs for optimizing the communication links are the following:

TCP window spoofing for handling long packet delays Running robust TCP variant between PEP on MAR and tunnel server for:

o Handling packet loss / bit error on the linkso Handling fast changes in bandwidth / delay product when links switch or

links are bundled / unbundledo Both phenomena cause standard TCP to go frequently into slow-start

mode causing considerable under usage of the available bandwidth In line ZIP proxy In line JPEG2000 proxy Bit string cache with learning dictionary

Since the last 3 items require much RAM memory and local storage, we proposed an alternative HW platform for the Geode CPU.

2.1.2.3 Billing, Authentication and PortalThe access gateway onboard of the train acts as a DHCP server for the restricted access VLAN and provides controlled access to onboard content and the Internet.

Basically a very simple captive portal is part of the delivery, on which the passenger onboard of the train has to push the “I agree” button, before access is granted to the system. The basic portal is built on an industry-standard web server and written in widely known languages like PHP. This allows easy customization by designers who don’t need to be aware of all details of the onboard infrastructure.

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Solution description

Figure 6: Example one-click portal

When a more elaborate portal is required this can be considered together with the portal design.

On top of this portal a more extensive portal including more elaborate content could be created. This portal created could contain following functions:

A mix of free content, non-free content and Internet access. Access by a not-yet-logged-in user to non-free content and the Internet is intercepted and the user is presented a login screen.

For each user the status of his connection can be shown, with indication of date, time how long connected.

Another option is showing the current train location on a moving map. An interface with an authorization server via the industry-standard Radius

protocol, to get an access granted or denied decision. After login, the access gateway can start to send accounting records to the Radius (AAA) server, to allow detailed billing per user. It is possible to assign a class when a user logs in and then send this class along with the accounting records.

The combination of the onboard authentication software, the basic portal and the on land Proxy AAA in the central data centre allows a very easy connection/integration with the Radius AAA sever at the ISP location. In this way the ISP could offer the on train passengers exactly the same billing functions as supported on his own Radius AAA system. This could be pre-paid billing, subscriptions, payment by credit card and others. All info received on the train is forwarded one to one to the Radius AAA of the ISP. In case other information is needed additional configuration will be needed.

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Solution description

Figure 7: Extended portal example - Thalys

2.1.2.4 Fleet Network Manager – train clientOn board of the train all data is collected by the Smart Management Proxy. This SMP wraps a management interface around the onboard equipment that you want to monitor via SNMP or other connections interfaces. All data is sent to the FNM – Train Client that will store all data onboard of the train in the ‘data collector’. Before sending the collected data through to land all data is processed so bandwidth usage is minimized.

The onboard FNM – Train Client will also be contacted and activated when performing remote interventions like upgrades, content updates and others on the train. For example, scripts can be triggered via SNMP set commands. This way it is possible to build a set of procedures that can be triggered by the operational staff. Examples are a firmware updates, software resets, and others.

2.2 Roof top antennaPossible scenario:

One Sencity Excel bi-directional WiFi antenna for rooftop mounting and for 2G/3G and GPS.

One Sencity Excel bi-directional WiFi antenna for rooftop mounting for LTE. A basic coax cabling set for the connection between rooftop antenna and main

rack (standard length in offer 12m) A metal mounting plate

The 2 2G/3G modems are combined via an antenna combiner and connected to one antenna. Cabling between the antenna and the main rack is part of our proposal (12m). In case the length is different a price adjustment might be necessary. This will become clear after the site survey.

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Solution description

2.3 The secondary rack: WDS200Passengers or staff can connect their WiFi enabled device via the WiFi antennas to the access points in the coaches. Each coach is equipped with 1 WDS200. The WDS200 unit is a preconfigured unit containing a double access points and a power supply.

Figure 8: Schematic drawing on train network

The compact sizing of the unit allows an easy built-in into your train. The access points for passenger WiFi access use Wireless LAN standards 802.11b (11 Mbit/s) and 802.11g (54 Mbit/s) which ensures that the onboard service is compatible with various devices such as notebooks, PDA’s, mobile phones…Between the coaches the 802.11a (5GHz) standard is used as this is a more stable connection. This antenna is installed indoors at end of the coach in the middle of width of the coach. If required an external antenna is also available. It is possible to configure secure connections for staff access or applications.

Figure 9: WDS200 unit

2.3.1 Technical data

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Solution description

The WDS200 consists of following railway compliant units:

A AC/DC 110 V power supply unit. It is assumed that for connection of the power (110Volt DC) a power cable with connector is delivered by the customer. For each secondary rack a power cable with Wago connector Model 231-2110/037-000 needs to be available on the train.

A CPCI frame with one backplane. One double access point is used as a WDS bridge for the connections between

the coaches. The WDS bridges will be configured for using the 802.11a frequency band, as to avoid possible interferences with the 802.11b,g radio signals for the user’s WLAN access. All these WDS bridges in the coaches together form the wireless in-train backbone. The second part of the access point will be used for WLAN access for the passengers. The access points can be configured with up to 16 virtual access points (VAP), as to provide secure access for different applications, via one physical device. Every VAP can be separately configured with its own SSID, access security rules, and mapped to four QoS queues, each linked to a VLAN on the backbone network.

Two fast Ethernet connectors using D-coded M12 connectors for external devices, one is used to connect to WDS100

WLAN antennae support N-connectors.

In addition to WDS200 following WiFi antennas are part of our proposal:

2 Omni-directional 2.4 GHz WiFi antennas for passenger usage.

Standard is a 30 m cable to connect the WDS200 with the main rack. If during the site survey it seems that different cable lengths are required, prices might change slightly.

Both secondary rack configurations have following technical specifications:

DIMENSIONSFrom -25 to + 60°C ( +/- 0,5°C delta)

-45 to + 85°C ( system degradation possible )

WEIGHT12 Watt nominal (15Watt max )

Input voltage between 16,8 – 50 VDC

POWER SUPPLY65 x 200 x 360

POWER CONSUMPTIONN-type, M12 D-coded, Wago

TEMPERATURE RANGESSupport up to 95% RH non-condensing

CONNECTORSEach side contains two M5 stifts for unit fixation.

RELATIVE HUMIDITY+/- 2,9 Kg

RAILWAY APPROVALSEN50155

Figure 10: Technical specification WDS200

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Solution description

2.3.2 Features

The following features are integrated as a standard in the secondary units.

Provision of data transfer between coaches: theoretical throughput is 54Mb. Enable special access for train staff or train applications: the access points

used in the WDS200 can use multiple SSID/VLAN combinations per radio card, each with its own authentication and encryption method This

Secured user access: built in security that prevent passengers to connect to other users

Automatic Wireless reconfiguration: when adding or changing coaches from train sets the wireless train backbone automatic configures or reconfigures without the need of a human intervention.

Support of SNMP by all components

Designed and manufactured according to railway standards (EN50155, FCC class B, CE approval)

Optional: redundant configuration: It is possible two use two WDS200 to provide for redundancy on both the user access level as on the train backbone level. The redundancy can by provided by either the spanning tree protocol, or by using service sensors. This last method allows for using both legs simultaneously in the wireless train backbone, doubling the available bandwidth, while spanning three only allows the use of one leg at the time in the redundant configuration.

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2.4 Optional: Certification of main equipmentWhen changes to the standard solution (CG6400, WDS200, ) are needed a re-certification might be needed. If certification testing will be performed; below is a description of a possible test scenario,.

Certification tests EMC:o Compliance test EN 55011

o Radiated emission: 30 - 1000MHz @ 3m, Class Ao Radiated emission: 230 - 300MHz @ 3m, 50dBμV/m.o Radiated emission: 151 - 157MHz @ 3m, 32dBμV/m.o Radiated emission: 457,40 - 458,45MHz @ 3m, 22dBμV/m.A30o Radiated emission: 467,40 - 468,45MHz @ 3m, 22dBμV/m.

o Compliance test EN 50121-3-2.o Conducted emission DC power ports: 0,15 - 30MHz.o Conducted emission I/O power ports: 0,15 - 30MHz.o EFT DC power ports: +/- 2kV.o Surges DC power ports: +/- 1,8kV.o Conducted RF DC power ports: 0,15 - 80MHz, 3Vrmso Variations / Interruptions DC power ports: see EN 50155.o EFT I/O ports: +/- 2kV.o Conducted RF I/O ports: 0,15 - 80MHz, 3Vrms.o Radiated RF enclosure ports: 80 - 1000MHz, 10Vrms.o ESD enclosure ports: +/- 6 / 8 kV

Certification Safety:o Compliance test EN / IEC 60950-1o Compliance test EN 50153

Klima, vibration test / EMC testingo Compliance test EN 50155:

o Cooling test: “Dry cold” according EN 60068-2-1o Heat test: “Dry heat” according EN 60068-2-1o Temperature measurement in housingo Air temperature above PCB’s o Over-heating, 10 min., start-up

o Compliance test EN 61373:o Functional vibration test.o Vibration endurance test, X, Y en Z as, 5h/as, total 15ho Vibration endurance test, X, Y en Z as, 1h/as, total 3ho Shock test.

A final certification plan needs to be discussed between the customer and Nokia Siemens Networks.

All certification must take place before the installation of any equipment on the train. If equipped is already installed before certification and problems occur Nokia Siemens Networks cannot be held responsible for necessary changes.

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Solution description

2.5 On train TV screensThis is a 18.5” or 21.5” LCD display with integrated media player hardware. This master display is connected to the network (WLAN, GPRS, 3G,…) and if applicable to the on-board vehicle computer of the bus to retrieve real time travel information. A security camera can be connected to this 18.5” or 21.5” Mobile Master with a composite video input. Optionally, an analogue PAL/SECAM tuner can be embedded in the Mobile Master display.

Panel size 18,5-19" 21,5"Resolution 1366x768 1920x1080Aspect ratio 16/9 16/9Colour depth 16,7 M16,7Brightness 300 cd/m² 300 cd/m²Contrast 800/1 1000/1Viewing angle vertical 170° horizontal 160° vertical 170° horizontal 160Response time 5ms 5msLamp life time 50.000 hours 50.000 hoursPanel type tv general

Embedded player specifications:

o Based on Intel 945 chipset and Atom processor @ 1,6Ghz o 1Gb RAM memory & 4GB on-board storage (industrial CF) o 1x Ethernet 10/100/1000 o 2x USB o 1x RS232 & 1xRS485

The display solution with embedded player is compliant with EN50155, T1:

o fully operational when environmental temperature (temperature in vehicle nearby equipment) ranges from 0 to 55°C

o short-term (max. 15 minutes) startup conditions with environmental temperatures up to 15°C higher

o Powering the equipment in case of negative environmental temperatures (-25 till -1°C) will not damage the electronics; the solution is equipped with an automatic fail safe mode for these specific conditions. The equipment will become fully operational when internal equipment temperature reaches 0°C.

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Solution description

Figure 11: 18,5 inch screen measurements

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3. Services proposalNokia Siemens Networks provides Care Services as described in this document consisting of Software and Hardware Services towards Siemens to ensure highest availability of the solution.

3.1 Support ModelFigure below illustrates on a high level the support model and his stakeholders. Details for all Maintenance Services provided by Nokia Siemens Networks are defined in following chapters.

Figure 12: overview Support Model

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1 © Nokia Siemens Networks

R 255 G 211 B 8

R 255 G 175 B 0

R 127G 16 B 162

R 163 G 166 B 173

R 104G 113 B 122

R 234 G 234 B 234

R 175 G 0 B 51

R 0 G 0 B 0

R 255 G 255 B 255

Supporting colors:

R 52 G 195 B 51

Primary colors:

NSN R&D• 8x5 GMT+2• SLA according L3

3rd party suppliers• Warranty only• Spare on-site

Service process

Alarm SurveillanceIntervention planning

First Line Maintenance (FLM)

Field Service On site

PerformanceMonitoring

Repair and replacement Service

ContentRelease & admin

Remote Maintenance*

On site request

Level 1 – 18/7

By NSN

Level 2 – 8/5

By NSN

Qualify case and define next steps:• Remote troubleshooting • prepare workaround• trigger onsite intervention by Field service (replacement, hard reset, …)• escalate to L3 and partners

Handle spare parts, test and if repairable follow process

NSN Ticket Tool 18/7Response times during office hours 8/5

OPTIONAL

*According to procedures in Fleet Network Manager (restart system, VPN test, …).

No on-site support by NSN is foreseen

NSN emergency service times 06:00 – 24:00 for critical faults

*According to procedures in Fleet Network Manager (restart system, VPN test, …).

No on-site support by NSN is foreseen

NSN emergency service times 06:00 – 24:00 for critical faults

Rem

ote

Telephone, Mail, SMS

Level 3 – 8/5

By NSN

Field Service On site

Passenger + Billing + portal Helpdesk

Emergency support for critical fault 18/7, by phone

Customer SpareStock On-site

To be defined

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Solution description

4. Abbreviations

AAA Authentication, Authorization, AccountingAC Alternating CurrentADSL Asynchronous Digital Subscriber LineAJT Average Journey TimeARPU Average revenue per userASP Application Service ProviderBER Bit Error RateBS Base StationBW Bandwidth (in the sense of data throughput)CAPEX Capital expenseDC Direct CurrentDHCP Dynamic Host Configuration ProtocolDNS Domain Name SystemEAP Extensible Authentication ProtocolFDD Frequency Division DuplexingFMM Fleet Management MonitorFTP File transfer protocolGMUD: Generalised multi user detectionHNS bandwidth management systemHW HardwareINC Integrated Network ControllerKPI Key performance indicatorsLAN Local Area NetworkLTE Long Term EvolutionM2Y Music to You / Media to YouMAC Media Access Control MAR Multilink Access RouterMbps Mega bits per secondMIB Management Information BaseMIMO Multiple Input Multiple OutputMLE Multilink Endpoint RouterMNO Mobile network operatorMS MicrosoftMVB Multifunctional Vehicle BusNOC Network Operations Centre NSP Network Service ProviderNTP Network Timing ProtocolOPEX Operational expenditurePDA Personal Digital AssistantPEP Performance Enhancement ProxyPerformance Enhancement Proxy (PEP)QoS Quality of ServiceRNC Radio Network ControllerRoF Radio over FibreRSS Really Simple Syndication (Web feed format)SLA Service level agreement

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SMP Smart Management ProxySMTP Simple Mail Transfer ProtocolSNMP Simple Network Management ProtocolSSID Service Set IdentifierTCS Train Communication SolutionTDD Time Division Duplexing TOC Train Operator CompanyTS Tunnel ServerVAP Virtual Access PointsVLAN Virtual Local Area NetworkVoD Video on DemandVoIP Voice over IPVPN Virtual Private NetworkVSAT Very Small Aperture TerminalWDS Wireless Distribution SystemWDS Wireless Distribution SystemWiFi WLAN standardWiMax Worldwide Interoperability for Microwave AccessWISP Wireless Internet Service ProviderWLAN Wireless LANWPA WiFi Protected AccessWPA-PSK WPA with pre-shared keys

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