Workshop ILC 150 GSM/GPRS Worldwide Communication in Automation Frank Walde

Agenda Abstract GSM / GPRS History Technology Topology GSM / GPRS in Automation General Application Notes Controller Configuration SMS GSM / GPRS Remote Access Machine to Machine IP Communication Workshop

History of GSM Technology 1982 The European Conference of Postal and Telecommunications startet the development of mobile phone system Groupe Spécial Mobile (GSM) 1990First GSM Testgrid started in Finland 1992Operation of 13 GSM Networks in 7 countries 2000Introducing of GPRS (General Packet Radio Service) for packet based Data Communication (IP, X.25) 2006Nearly Worldwide access to GSM Networks (213 countries / 147 networks) and approx. 2 billion User!!

GSM TechnologyBasics Standard for digital Voice- and Datacommunication Operation in 4 different Frequency band (Quadband) 850 / 1900 Mhz*America 900 / 1800 Mhz* Europe, Asia, Africa, Australia Channel Access via FDMA (Frequency division Multiple Access) and TDMA (Time division multiple Access) Cell Based Topology. Mobile Phones roam between different cells * Since HW05 Quad Band is supported by ILC150GSM

FDMA in GSM FDMA (Frequency division multiple access) e.g. 900 Mhz 124 Channels available 890 to 915 MHz: uplink (mobile to BTS) 935 to 960 MHz: downlink (BTS to mobile) …but by far not enough

TDMA in GSM TDMA (Time division multiple access) Each Frequency Channel divided into 8 Timeslots Both together leads us to… Communication Burst. More Types of Burst defined in the standard, but not important for the practical use.

FDMA and TDMA in GSM

Under Best Conditions there are 992 Mobile devices possible in each cell But, practically there are only 20 – 100 Frequency Channels useable (fading, noise, reflections) with 8 timeslots 160 – 800 devices possible Voice and SMS have a higher priority than Datatraffic

GSM Networks TopologyI BTS:Base Transceiver Station MS:Mobile station (Phone or Modem) BSC:Base Station Controller MSC:Mobile Switching Center

GSM Networks TopologyII HLR:Home Location Register (Central Register of all MS in the Provider Network) VLR:Visited Location Register (Temporary Local Register of all MS in the MSC Area, used for e.g. BTS Roaming) ASC:Authentification Center of the Service Provider

GSM Networks TopologyIII (Authentification) Connect to the Base Cell Station (Radio Cell) VLC Registration in the Network (MSC) GMSC HLR AUC MSC sends the Request to the HLR/AUC (Is the User permitted to use the Network and wich Services are allowed) In case the User is allowed to connect the HLC informations are copied to the VLC The User is registered completely and can communicate with the providers network. BUT, please keep in mind! If the User is not registered in the AUC to use GPRS, SMS, free Connection and so on it wont be possible. Also not with the ILC 150 GSM!

GSM Networks TopologyIV (Cell Structure) The Radiocells in a GSM Network are organized in a hexagon overlapping setup theoritical Setup realistic Setup

Summary GSM Technology Cell Based Communication Simultaneously use of 160 – 800 devices in each cell possible (more registered devices in the VLR/HLR possible) Voice and SMS have a higher priority than Datatraffic GSM direct dial up 9,6kBit/s = ~1kByte/s max. GPRS packet based IP Communication Downlink: 38,4kBit/s = ~ 4kByte/s max. Uplink: 19,2kBit/s =~ 2kByte/s max. The size of a Radiocell may vary depending of the environment and of the amount of users from ~100 m … ~35km

Questions ?

But for what does GSM, GPRS and SMS stand for and how can we use it ??

GSM (Global System for Mobile Communications) 0171 / / Point to point connection via direct dial-up Time based billing Transmission speed 9600 Bit/s Always one Timeslot

SMS (Short Message Service) 0171 / / SMS is always send to the Short Message Service Center and than forwarded to the addressed mobile Higher priority than Datatraffic (GPRS) but lower than GSM If the addressed mobile is not available the SMS will be stored in the HLR and send on the next login of the device Provider SMSC SMSC = Short Message Service Center Confirmation 0171 / 56789

GPRS (General Packet Radio Service) )))))) (((((( GPRS / Internet IP Static IP (APN) IP IP IP IP IP Dynamic IP address allocated by the provider No direct dial-up to the modems (for standard networks) Data volume based billing -> always online Transmission speed max Bit/s (theroetical / asynchron) Depending of the channel coding and number of channels Practical Performance Downlink: Bit/s Uplink: 19200Bit/s Max. 4 Slots up and Downlink, together max. 5 Slots Provider

Gateway GSM/GPRS in Automation Internet GSM is a so-called cellular network In every cell, a limited (20-100) number of transmission channels are available Each channel can be used by 8 devices simultaneously 160 – 800 devices possible

Gateway GSM/GPRS Normal Use Internet Theoretically obtainable data rates GSM (9,6kBit/s = ~1kByte/s max.) GPRS Downlink: 38,4kBit/s = ~ 4kByte/s max. Uplink: 19,2kBit/s =~ 2kByte/s max. Uplink Downlink Client - Mobile Browser - Web Server Mail Server

Gateway GSM/GPRS in Automation Internet Theoretically obtainable data rates GSM (9,6kBit/s = ~1kByte/s max.) GPRS Downlink: 38,4kBit/s = ~ 4kByte/s max. Uplink: 19,2kBit/s =~ 2kByte/s max. Server - WebServer (WebVisit) - PC WorX Client Uplink Downlink

Gateway GSM/GPRS in Automation Internet Lets assume: Open a WebVisit-Visu with standard browser (iExplore, Firefox, etc..) For displaying the first web page, a data volume of 256kBytes has to be transferred Via GSM with 1kByte /s it takes at best 256 seconds until a display is seen. Via GPRS with 2kByte/s (in Uplink) the loading takes at best 131 seconds. By using the MicroBrowser, only approx. 15kBytes have to be transferred per page. This leads to the following loading times: GSM with 1kByte/s -> 15 seconds GPRS with 2kByte/s -> 7,5 seconds Uplink Downlink

Provider Issues The ILC is connected in the GSM/GPRS Network and I can send Mails and SMS but the Remote Access is not working. What's wrong...? GSM / GPRS ?

Provider Issues Most network Providers do not allow access from the outside (via GPRS). --> Not common customer application Remote maintenance (via GPRS) and Machine to Machine communication is only possible with a special mobile phone contract and maybe additional services. This services (e.g. CDA with Vodafone) has to be bought where necessary and paid for in addition.

Vodafone CDA Server The Vodafone–Server assign the private IP address by identifier of the SIM card Closed private network via GPRS IP Internet VPN - Tunnel IP GPRS CDA Server 3.0 Router (((((( (((((( IP

Summary GSM/GPRS in Automation Easy Status information with SMS (Lifesign, Alarming …) IT Information Technology ( , IP- Communication) Easy distributed Machine to Machine Data Exchange Worldwide Remote Access and Monitoring (e.g. PC WorX, WebVisit) BUT: Performance of Analog Modems (9600 kBit/s of ~ 1995) Not today ADSL 16 MBit/s Speed

Important Application Notes The network is designed for mobile devices with uncrittical information traffic. No provider will guarentee a 100% availability. Sporadically downtimes of ~30 min could happen (and sometimes even more) A delaytime of 1-2s on a IP Frame over GPRS is normal. Because Voice has a higher priority than Datas the Provider buffers IP Packets in periodes of busy network. In this case the delaytime could be a few minutes. There could be events (e.g. uncomplete Logouts) wich could make a Modem Reset from the Application site neseccary. invalid IP (e.g ) Modem_Connect Valid gone for more than 10 min To prevent inactivity or time Logouts from the Provider we recommed a 24h reconnection to the GSM Network When the GPRS should be used the standard Gatewayadress of the LAN should not be used. Because then the Controller tries to answere incomming GPRS request over the LAN Gateway. WAN access via LAN and GPRS is not possible!

Firmwarehistory FW 220 HW <=4: GPRS or SMS Not GPRS optimized Modem wont handle connection problems No hard Modem Reset possible BUG: Special Characters can block the SMS Engine FW 354 HW 5: SMS all characters allowed GPRS and SMS possible at the same time (CMUX) Modem tries to keep the connection alive (GSM/GPRS) GPRS Portfilter BUG: For some reasons the Modem blocks (error 0x14, 0x07) only power Reset can solve it. BUG: instable GPRS connection FW 358 HW 6: stable GPRS Handling Improved Modem handling of the ILC FW should prevent Modem crashes (Emergency exit) Application Modem Reset possible (Mode 255) Change of the Resetbutton, a blocking of the button during the shipment is not longer possible

Questions ?

Controller Configuration in PC WorX Open new project

Controller Configuration in PC WorX Assign IP address Attention : Do not define standard gateway Please leave field empty No simultaneous communication to third-party networks via GPRS and Ethernet since there is only one network card in the device!

Controller Configuration in PC WorX 1. Enter PIN 2. Set SMS service center 3. Enter permitted service numbers (These telephone numbers may dial in to PLC) 4. Define user name and login For remote programming via dial-up line (GSM): 5. Transfer the Settings into the ILC150 GSM

Controller Configuration in PC WorX 1. Enter GPRS user data 2. Select if GPRS shall be active already at the start. (If active, no other GPRS component is necessary; if not active, the GPRS component has to be used to switch on) 3. Activate port filter if need be (If port filter is active, no access via GPRS to the FTP area and with PC WORX is possible any longer) For remote programming via dial-up line (GPRS):

SMS Sending SMS to a Mobile Phone

GPRS

Sending an via GPRS (SMTP Client out of IT_Library) SMTP Server Internet Internet-Gateway Mobile radio network SMTP Client Open DNS Server recommed (e.g. OpenDNS.com)

SNTP GPRS / Internet IP SNTP Server IP SNTP Client

GSM Remote Access 0171 / (((((( 0160 / With PC Worx and WebVisit Remote Phonenumber must on the white List!

GPRS Remote Access (((((( GPRS IP IP IP IP IP IP CDA Server 3.0 With PC Worx and WebVisit Only possible with an open GPRS connection (external access allowed, no Port Filter)

Machine to Machine Communication (((((( GPRS IP IP IP IP IP CDA Server 3.0 )))))) IP Important : The timeouts must be configured, because the default values could be critical in a GPRS network (Default Send: 750ms / Receive 5000ms)

Failure Handling / GSM Modem_Connect not valid for more than 10 min. GPRS_Connect without Datatraffic or IP not valid (previous reconnect without success) Unable to send a SMS after several trials Mode int#255 activates a hard Modem Reset. The Modem performe a complete reboot and will establish a new connection to the GSM network

Failure Handling / GPRS GPRS_Connect without Datatraffic or IP not valid Enable = false; wait approx. 15 min Enable = true GPRS was working, but after a few reconnects the Connect gives FF03/4 Some Provider does not allow many reconnects in a short time (e.g. 2 times in 10min). In this case wait for the next try ~ 30min. Recommendations: Close the GPRS connection when no communicatuion is necessary (e.g. after sending an ). min. Time connected to GPRS ~10 min Delay Time for a reconnect to the network ~15 min / ~30min

Troubleshooting / FAQ

FAQ Mobile_Connect cant access the GSM Network Is the SIM Card correctly inserted and Pin correct? Check the Modem Parameter or the PC Worx Modem settings. The SMS_Send seems to be working, but the SMS is not received Ask your Provider for the SMS Servicecenter No. and check the Destination Adress. GPRS Connect Quits with Failure FF0X Make sure the GPRS Settings are correct (APN, User, PW) and saved into the ILC150 GSM/GPRS (perform after the download a Power Reset) GPRS was working, but after a few reconnects the Connect gives FF03/4 Some Provider does not allow many reconnects in a short time (e.g. 2 times in 10min). In this case wait for the next try ~ 30min.

FAQ II Remote Access is not working Standard mobile contract blocks all incomming Traffic! (ask your Provider) Local firewalls does not permit communication (frequent source of errors within Phoenix Contact) Instable GSM Connection (Weak Signal Strength, slow GPRS connection, Connection losses) Check antenna SMA connection Signal Quality sometimes poor in inhouse installations (if possible outside antenna installation) Reception quality and cell capacity have to be clarified before with the provider.

Thank you very much for your attention