Communication Controller with IP services for leased lines and wireless links Radio Activity S.r.l.

Transcription

1 Communication Controller with IP services for leased lines and wireless links Radio Activity S.r.l. Registration CCIAA Milano No P.I./C.F.: Head office and Operational headquarter: Via Ponte Nuovo Milano Italy Phone: Fax/Voicebox: info@radioactivity-tlc.it

2 Summary General Description...3 Reference Drawing...5 Time Measurement...6 Analogical Wireless Link through RA-450D/RA-160 TRX...7 Serial-to-Serial Connection...9 -to- Connection...10 Unfiltered LAN Extender...10 Filtered LAN Extender...10 Notes about the LAN Extender Modes...11 LAN Forwarder...11 PPP Forwarder...11 Notes about the LAN Forwader and PPP Forwader Modes...13 LAN V.24 asynchronous Connection...14 Serial-Connected Remote Target...14 Serial-Connected Control Centre...14 Valid Settings...16 Remote Monitoring and Surveillance...17 Coupling the to an RA-450D/RA-160 TRX...19 Technical Data...20 Embedded Analogic DCE Characteristics...20 Ports and Connectors...20 Environmental Parameters...20 Power Supplying...20 Mechanical Characteristics...20 Equipements...20 Page 2 of 20

3 GENERAL DESCRIPTION is a Communication Controller composed of an embedded analogical DCE and a high performances RISC processor, equipped with LINUX operating system, which manages the whole device and handles the HW/SW communication interfaces needed for serial and LAN ( 10BT/100TX) data ports. The embedded analogical DCE is designed to work on a standard 2/4 wire interface, with the availability of E&M signalling, using the V.34 standard; it is optimized to carry the data flow on a narrow band audio channel ( Hz), so it can be well coupled to carriers like analogical TRX, power line boosters, audio networks, and so on For wireless links we recommend to use TRXs of the RA-450D/RA-160 family, which have excellent radio electric characteristics, adapted to realize high-speed data point-to-point links. You should note that the RA-450D/RA-160 TRXs process the signal through DSP (Digital Signal Processing) devices, permitting lots of functions not performed by the traditional analogical TRXs. In particular, the link established by these TRXs, even with a 12.5 KHz channelling, guarantees a real Hz bandwidth with very low levels for group delay and distortion, and a high S/N level. The link between two will be a persistent point-to-point link. The typical application is the TCP/IP network extension toward remote networks or single network devices operating process control (electrical production, surging sites ). Available on the are: a V.24 asynchronous serial port reserved to the remote control system, allowing the monitoring and the surveillance of both the local and the remote Device, a V.24 asynchronous serial port for the data communication, a 10BT/100TX LAN port for the data communication. Page 3 of 20

4 The handles the communications between the serial ports, the LAN port and the embedded DCE. It has its own configurable IP Address, and carries the data on a 2/4 wire line using a full-duplex PPP protocol. The can transfer data on a point-to-point wireless link, realized with a couple of RA-450D/RA-160 TRXs, at a speed up to 26.4 Kbps, assuring a 19.2 Kbps net bandwidth and using the extra band for diagnostic signalling, error correction and network services. Using a RISC processor with an embedded LINUX operating system assures a great flexibility for configuration and use, permitting either homogenous LAN-to-LAN or V.24-to-V.24 and mixed LAN-to-V.24 connections: Device 1 data interface Device 2 data interface V.24 asynchronous serial port V.24 asynchronous serial port V.24 asynchronous serial port 10Base-T/100TX (TCP/IP) 10Base-T/100TX (TCP/IP) V.24 asynchronous serial port 10Base-T/100TX (TCP/IP) 10Base-T/100TX (TCP/IP) 10Base-T/100TX (RAW) 10Base-T/100TX (RAW) The power supplying is compliant with the greater part of the Telecom Companies Standards, at 19 65V, floating ground. Page 4 of 20

5 REFERENCE DRAWING The typical function is to perform a full-duplex point-to-point data transfer through an analogical audio transport network, as shown below: Serial Control Port TCP/IP / V24 Data Network Control Centre Asynchronous V.24 serial Local Device Transport network TCP/IP / V24 Data Network Remote Target Asynchronous V.24 serial Remote Device Serial Control Port The data interfaces can be an 10BT/100TX port or a V.24 asynchronous serial port. The control port is a V.24 asynchronous serial port, and can be connected through the usual diagnostic channels transport network. Through the control port the user can carry out the complete configuration of the Device and perform remote monitoring and surveillance, on both the local and the remote Devices. All the data transport configurations specified in the next sections are available on the. Page 5 of 20

6 TIME MEASUREMENT To perform the time measurement, this configuration has been built up: LAN Switch Local TCP/IP network Device A LAN Switch TCP/IP Host IP Address /24 (irrelevant) TCP/IP Target IP Address /24 Device B 4 Wire + E&M (crossed) IP Address /24 cross-cable IP Address /24 (irrelevant) The measurement has been made using the PING command, which sends an ICMP packet called ECHO_REQUEST, waits for an ICMP packet called ECHO_REPLY as its answer, and computes then the time spent between the dispatch of the ECHO_REQUEST and the arrival of an uncorrupted ECHO_REPLY (that is, containing the same data sent); the measure obtained is the round-trip of the system in real working conditions, with a low network traffic. Different tests have been made using different PINGs toward the target at different connection speeds and different packet sizes; for every test the connection speed between the devices has been verified. The latency and round-trip times got are shown in the following table: Packet size (data+header) [byte] Connection speed [Kbps] Minimum round-trip time [ms] Mean round-trip time [ms] Maximum round-trip time [ms] 32+82= = = = = = = = Latency [ms] Page 6 of 20

7 ANALOGICAL WIRELESS LINK THROUGH RA-450D/RA-160 TRX A full-duplex persistent narrow-band point-to-point wireless link can be used as a transport network: this can be easily built with a couple of RA-450D or RA-160 TRX, which is the best for a data flow transport. RA-450D RA-160 RA-450D RA-160 The use of a RA-450/RA-160 TRX as carrier allows excellent performances about the reliability of the link, as shown in the following table (this field report is for RA-450D): Link type Availability degree Yearly downtime [hours] 450 MHz point-to-point wireless link performed by RA-450D 99.99% <1.0 h Digital Leased Line (E1) link 99.96% 3.5 h Satellite link 99.60% 35.0 h Moreover, the analogical data flow on a standard 2/4 wire + E&M interface can easily be carried on an existent audio transport network, in the case of a long distance between the TRX and the. The next figure shows a possible extended version of the Reference Drawing (example is for RA-450D, but is applicable for a couple of RA-160 also). TCP/IP / V24 Data Network Control Centre Asynchronous V.24 serial Device A RA-450D RA-450D E&M MUXF E1 TCP/IP / V24 Data Network Remote Target Asynchronous V.24 serial Device B E&M MUXF E1 Transport network DN2 DN2 Page 7 of 20

8 A couple of can be connected directly through the RA-450D/RA-160 audio channel and/or through an audio transport network with 2/4 wires + E&M phone channel, w/ or w/o using E&M signalling. The RA-450D/RA-160 TRXs permits strong data links on a distance of tens of Kilometres because of both its sensivity ( dbm / -90 dbm) and its available RF power (up to +43 dbm). Next you can see some typical performances of a couple of through a RA-450D wireless link: RX field [dbm] Device A speed [Kbps] Device B speed [Kbps] Devices A - B S/N ratio [db] Page 8 of 20

9 SERIAL-TO-SERIAL CONNECTION This is the basic operating mode: it realizes a transparent serial data transfer. Device A Asynchronous V.24 serial Transport network Device B Asynchronous V.24 serial The LAN is not involved; therefore no IP Addresses or other LAN parameters are required. The serial ports can be configured with: Speed (between 600 bps and Kbps) Character length (7 o 8 bit) Parity (none, even, odd) Flow control (Hw - RTS/CTS - or none) All the data transmitted over the data serial port are transparently transferred to the data serial port of the other Device. The amount of communication delay is mainly due to the transport network. Both the Devices must be configured as Serial Forwarder. Page 9 of 20

10 ETHERNET-TO-ETHERNET CONNECTION A couple of linked through a transport network can perform a direct connection between two LANs or two LAN segments. The following operating modes are possible. UNFILTERED LAN EXTENDER With this operating mode, both the s don t need a specific IP Address or a Subnet Mask. All the data packets on the port are transparently transferred to the port of the other Device in RAW mode. Because of the limited bandwidth of the analogical data channel (with respect to speed), interposing a device like a switch or a gateway or a router in the Control Centre prior to the is a better choice. The reference drawing is as follows: Device A TCP/IP Data Network Control Centre IP Address (PPP) /24 IP Address /24 IP Address /24 Connect to /24 Device B Transport network TCP/IP Data Network Remote Target 2/4 Wire + E&M IP Address (PPP) /24 The Remote Target is visible as it were a local device, so the Control Centre will make a direct connection to the Remote Target, to its IP Address; the IP Addresses of Control Centre Hosts and Remote Target must belong to the same Network Address. FILTERED LAN EXTENDER The reference drawing and the main settings are the same as for the above mode ( Unfiltered LAN Extender ); the only difference is that both the s can filter the Addresses, just like a network switch. Therefore, a data packet will be transferred only if the Address of the addressee is included in the MAC dynamic tables of the connected to the sender. Filtering the Addresses dramatically reduces the traffic on the data channel and increases the bandwidth available for the data. A little portion on the band is anyway required for network signalling. Page 10 of 20

11 NOTES ABOUT THE LAN EXTENDER MODES Since all network packets sent to the port of one Device will be transferred to the port of the other in RAW mode, setting values for IP Address, Subnet Mask or Gateway Address are not required, unless the Control Centre plans to perform the remote control of the Devices through LAN. Moreover, inside the is present and active a PPP stack over the analogical DCE, performing the logical link between two Devices: the IP Addresses of the PPP stack of both Devices must belong to the same Network Address and must not belong to any other Network Address in the whole system. LAN FORWARDER This operating mode optimizes the transfer speed over the data channel by sending only the packets to be routed and minimizing the network signalling. The reference drawing is as follow: Device A TCP/IP Data Network Control Centre IP Address /24 Listen on Port xxxx Virtual Path IP Address /24 IP Address /24 Listen on Port yyyy Connect to /24 Port xxxx Device B Transport network TCP/IP Data Network Remote Target 2/4 Wire + E&M IP Address /24 Connect to /24 Port yyyy The Control Centre initiates a TCP/IP connection on the Device A, acting as a network server and listening on the port xxxx (user definable). The Device B acts as a network client, and initiates a TCP/IP connection on the Remote Target on the port yyyy. Once the LAN connection is established, the network packets going from the Control Centre to the Device A on the port xxxx will be transferred by the Device B to the Remote Target on the port yyyy, so the Control Centre looks at the Device A as it were the Remote Target (the Device A is a virtual target). Similarly, the network packets going from the Remote Target to the Device B belonging to this logical connection, will be transparently transferred by the Device A to the Control Centre. PPP FORWARDER Applying the PPP (Point-to-Point Protocol) over the data serial port of an allows connecting the Device in a LAN fashion to the Remote Target (or to the Control Centre) equipped with a serial communication port. Page 11 of 20

12 This means that the physical data communication channel will be a V.24 asynchronous serial line with a point-to-point network protocol applied on it; therefore the logical link between two Devices interconnected in this way will act as a TCP/IP Data Network link. This operating mode is similar to the above one ( LAN Forwarder ), with one (acting as a server) connected to the Control Centre, and the other (acting as a client) connected to the Remote Target. A possible reference drawing for this mode could be the following: Device A TCP/IP Data Network Control Centre IP Address /24 Listen on Port xxxx IP Address /24 Connect to /24 Port xxxx Transport network Virtual Path IP Address /24 Listen on Port yyyy Asynchronous V.24 serial PPP IP Address /24 2/4 Wire + E&M Device B Remote Target PPP Port Connect to /24 Port yyyy The Control Centre initiates a TCP/IP connection on the Device A, acting as a network server and listening on the port xxxx (user definable). The Device B acts as a network client, and initiates a TCP/IP connection on the Remote Target on the port yyyy. Once the LAN connection is established, the network packets going from the Control Centre to the Device A on the port xxxx will be transferred by the Device B to the Remote Target on the port yyyy, so the Control Centre looks at the Device A as it were the Remote Target. Similarly, the network packets going from the Remote Target to the Device B belonging to this logical connection, will be transparently transferred by the Device A to the Control Centre. All above can be applied to similar reference drawings: PPP link on V.24 asynchronous serial port between the Control Centre and the Device A, and link between the Device B and the Remote Target; PPP link on V.24 asynchronous serial port between the Control Centre and the Device A, and PPP link on V.24 asynchronous serial port between the Device B and the Remote Target. The cable connecting the serial ports could be a normal DTE-DCE cable w/ or w/o flow control signals. Page 12 of 20

13 NOTES ABOUT THE LAN FORWADER AND PPP FORWADER MODES You should note that the Control Centre only will be able to initiate the TCP/IP connection, toward the Device A (and virtually toward the Remote Target). The Device B will initiate the TCP/IP connection toward the Remote Target after the Control Centre has established the connection toward the Device A. Similarly, when the connection is closed, the logic link just created will be terminated. The IP Addresses and the TCP Ports number are user definable and can be defined when the whole system is planned, but you should follow some rules: standard TCP ports number (e.g.: 23, 25, 80, 110, 111, 138, 139 ) must be avoided, the IP Addresses of the Control Centre and the Device A must belong to the same Network Address, the IP Addresses of the Device B and the Remote Target must belong to the same Network Address, the IP Addresses of the Control Centre and the Remote Target can belong to the same Network Address, because the two s logically decouples the two network segments, inside the is present and active a PPP stack over the analogical DCE, performing the logical link between two Devices: the IP Addresses of the PPP stack of both Devices must belong to the same Network Address and must not belong to any other Network Address in the whole system. Moreover, for the PPP Forwarder mode only: the IP Addresses of the PPP port and the port of the Device with the PPP stack configured and active, must not belong to the same Network address, the IP Addresses of the PPP port and the port of the Remote Target (or the Control Centre), if both are present, configured and active, must not belong to the same Network address. Page 13 of 20

14 LAN ETHERNET V.24 ASYNCHRONOUS CONNECTION Two s can operate as cross-connectors between LAN-connected and serial-connected Devices. The operating mode is quite similar to the described above LAN Forwarder mode. Two operating modes are available: serial-connected Remote Target or serial-connected Control Centre. SERIAL-CONNECTED REMOTE TARGET This is a common case. The Remote Target is equipped with a V.24 asynchronous serial port only, and must be connected to a TCP/IP Network. The reference drawing is as follow: TCP/IP Data Network Control Centre Device A IP Address /24 Listen on Port xxxx IP Address /24 Connect to /24 Port xxxx Transport network Asynchronous V.24 serial Device B 2/4 Wire + E&M The Control Centre opens a TCP/IP connection on the Device A, acting as a network server and listening on the port xxxx (user definable); the Device B is connected to the serial port of the Remote Target. Once the LAN connection is established, the network packets going from the Control Centre to the Device A on the port xxxx will be transferred to the Remote Target on the serial port, which answers to the Control Centre trough the serial port; so the Local Host look at the Device A as it were the Remote Target. The Device A will be set as LAN Forwarder ; the Device B will be set as Serial Forwarder. SERIAL-CONNECTED CONTROL CENTRE This is a very unusual case. The Control Centre is equipped with a V.24 asynchronous serial port, and must be connected to a Remote Target equipped with an port. The reference drawing is as follow: Page 14 of 20

15 Asynchronous V.24 serial Device A Transport network IP Address /24 Listen on Port yyyy Device B TCP/IP Data Network Remote Target 2/4 Wire + E&M IP Address /24 Connect to /24 Port yyyy The Device A will be set as Serial Forwarder ; the Device B will be set as LAN Forwarder. Page 15 of 20

16 VALID SETTINGS All the operating modes can be integrated in two operating classes: the Forwarder class, including the following operating modes: Serial Forwarder LAN Forwarder PPP Forwarder the Extender, class, including the following operating modes: Unfiltered LAN Extender Filtered LAN Extender For a properly working system, the two linked s must be both set to operating modes belonging to the same operating class (e.g.: Device A LAN Forwarder, Device B Serial Forwarder; both the modes belong to the Forwarder class). Two linked s set to operating modes belonging to different operating classes (e.g.: Device A Filtered LAN Extender, Device B PPP Forwarder) cannot work at all. Page 16 of 20

17 REMOTE MONITORING AND SURVEILLANCE The is equipped with a V.24 asynchronous serial port intended for remote control, status monitoring and surveillance. The serial port can be configured with: Speed (between 600 bps and Kbps), Character length (7 o 8 bit), Parity (none, even, odd), Flow control (Hw - RTS/CTS - or none). Through this port the can be totally configured. The remote Device (the one at the other end of the link channel) is visible on the same connection. The service communications between the interconnected s use the extra band of the data flow. Through this port, controls on operating parameters and status and diagnostic tasks can be activated: General Settings and Operating Modes, Measurement and adjustment of transmitted audio levels, Check of received audio level and S/N ratio, Check of the analogical DCE connection speed, Local and Remote Data Loop, for checking the Service Quality (not yet implemented), Generating and Decoding MF tones on the audio line (not yet implemented). More s, grouped at the same level (local or remote) can be accessed as shown in the following reference drawing: Addr 254 Local V.24 asynchronous serial Control Port Addr 2 Remote s 10 wires FLAT cable Addr 1 V.24 asynchronous serial control port toward Remote Control System Page 17 of 20

18 The V.24 asynchronous serial control port is externally mirrored on a connector through which all the Devices can be connected by a BUS cable (10 wires flat cable). This mirror port is equipped with decoupling devices, which electrically isolate the port when the Device is off. Page 18 of 20

19 COUPLING THE TO AN RA-450D/RA-160 TRX The is designed to work on 2/4 wires + E&M leased lines, so the data flow can be well transported by point-topoint full-duplex analogical wireless links: therefore the coupled to an RA-450D/RA-160 TRX creates the best possible working condition for a wireless connection. This TRX has excellent characteristics to perform a point-to-point narrow-band high-speed wireless link: extremely low values for noise, distortion and group delay; very high RX sensivity, true Hz audio bandwidth, 12.5 or 25KHz channelling, analogical signal processed by a DSP device, which allows lots of functions not carried out by the traditional analogical TRXs. The coupling of an to an RA-450D/RA-160 can be done by connecting a 4-wire cable (a twisted pairs cable is the best) between the LINE connector of the and the Laux0 connector of the TRX; on this connector, if E&M signalling from the are not used, a jumper must be inserted on the M signal contacts, to force the transmission state on the TRX. At last, using the appropriate control software programs (MD1_Manager on s and RA_Manager on TRXs), the following settings must be done: audio TX level:...-10dbm audio RX sensivity:...-38dbm RA-450D/RA-160 audio input level on Line 1 :...-6dBm RA-450D/RA-160 audio output level on Line 1 :...-6dBm RA-450D/RA-160 modulation:...fm RA-450D/RA-160 RF Power:...to be adjusted to have a field strength between -55dBm and -75dBm on the receiver at the other end of the link Page 19 of 20

20 TECHNICAL DATA EMBEDDED ANALOGIC DCE CHARACTERISTICS Used audio bandwidth Hz Modulation V.34 Error correction ITU-T V.42 LAPM o MNP 2-4 Data transmission speed on a wireless link performed by a couple of RA-450D/RA-160 TRXs PORTS AND CONNECTORS Depending from radio electric characteristics of the link (typical values): 26.4 > -80dBm -90dBm -100dBm LAN Port Serial data Port Serial control Port BUS control Port 10BT/100TX on an RJ45 socket RS232 V.24 asynchronous bps on a DB9 female connector RS232 V.24 asynchronous bps on a DB9 female connector TTL on a dual-in-line 10 pins male connector ENVIRONMENTAL PARAMETERS Operating Temperature C Storage Temperature C Relative Humidity Max 80% not condensed POWER SUPPLYING Nominal Voltage Max ripple Overvoltage protection treshold Polarity reversal protection Short-circuit protection Power consumption Vcc floating ground 30 mvpp 70V differential, 300V common mode -100 V Electronic protection with automatic restore and double fuse on input line <6 W MECHANICAL CHARACTERISTICS Dimensions Weight 240 x 40 x 160 mm 500 g EQUIPEMENTS The is equipped with I/O lines and power supply plugs. Available is the Software Program MD1_Manager, by which you can set all the parameters and operating modes of the Device and perform remote monitoring and surveillance. Page 20 of 20