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Honeywell XYR 400E User Manual

Honeywell XYR 400E User Manual

Wireless ethernet modem
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XYR 400E Wireless Ethernet
User's Manual
34-XY-25-26
Version 1
5/1/08

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Summary of Contents for Honeywell XYR 400E

  • Page 1 XYR 400E Wireless Ethernet User's Manual 34-XY-25-26 Version 1 5/1/08...
  • Page 2 In no event is Honeywell liable to anyone for any indirect, special or consequential damages. The information and specifications in this document are subject to change without notice.

  • Page 3: About This Document

    Honeywell does not recommend using devices for critical control where there is a single point of failure or where single points of failure result in unsafe conditions. XYR3000 is targeted at open loop control, supervisory control, and controls that do not have environmental or safety consequences.
  • Page 4 Facsimile: (602) 313-3293 Mail: Honeywell TAC, MS P13 2500 West Union Hills Drive Phoenix, AZ, 85027 World Wide Web Honeywell Solution Support Online: http://www.honeywell.com/ps Elsewhere Call your nearest Honeywell office. Training Classes Honeywell Automation College: http://www.automationcollege.com Version 1 XYR400E Ethernet Modem 5/1/08...
  • Page 5 Symbol Definitions The following table lists those symbols used in this document to denote certain conditions. Symbol Definition ATTENTION: Identifies information that requires special consideration. TIP: Identifies advice or hints for the user, often in terms of performing a task. Indicates a situation which, if not avoided, may result in equipment or work (data) on CAUTION the system being damaged or lost, or may result in the inability to properly operate...

  • Page 6: Table Of Contents

    EFAULT ONFIGURATION ............... 23 ONFIGURING THE NIT FOR THE IRST 3.4.1 Set PC to same network as XYR 400E..............23 3.4.2 Set XYR 400E to same network as PC..............26 ..................28 ETWORK ONFIGURATION ......................30 THERNET ....................31 ORMAL PERATION ....................
  • Page 7 CHAPTER FOUR DIAGNOSTICS.................. 65 ....................65 IAGNOSTICS HART ............... 66 IAGNOSTIC NFORMATION VAILABLE 4.2.1 Connectivity......................66 4.2.2 Monitor Communications ..................67 4.2.3 Statistics ....................... 68 4.2.4 Network Traffic Analysis..................68 ....................68 ESTING ADIO ATHS ........................69 TILITIES 4.4.1 PING ........................69 4.4.2 IPCONFIG .......................

  • Page 8: Chapter One Introduction

    The module will transmit the Ethernet messages on the wireless band at rates between 1 and 11 Mbit/sec. Network Topology The XYR 400E is an Ethernet device, and must be configured as part of an Ethernet network. Each XYR 400E must be configured as: Ethernet an “Access Point”...
  • Page 9 Access Point should be the “central” Ethernet Device unit. Client An Access Point could be used as a “Repeater” unit to connect two XYR 400E Clients which do not have direct reliable radio paths. Access Point Client Client Ethernet device Multiple Access Points can be set-up in a “mesh”...
  • Page 10 Bridge vs Router Each XYR 400E is configured with an IP address for the Ethernet side, and another for the wireless side. A Bridge connects devices within the same Ethernet network - for example, extending an existing Ethernet LAN. For a Bridge, the IP address for •192.168.0.34...

  • Page 11: Getting Started Quickly

    Set the XYR 400E address settings as per section 3.4 Save the configuration - the XYR 400E is now ready to use. Before installing the XYR 400E, bench test the system. It is a lot easier to locate problems when the equipment is all together.

  • Page 12: Antenna Installation

    Further information is detailed below. Each XYR 400E module should be effectively earthed via the "GND" terminal on the XYR 400E module - this is to ensure that the surge protection circuits inside the XYR 400E module are effective.
  • Page 13 However where the radio path changes because the XYR 400E is mounted on moving equipment, or if there is moving equipment in the area, then the solution is to use two antennas. Because the two connectors are separated, the RF signal at each connector will be different in the presence of multi-path fading.

  • Page 14: Dipole And Collinear Antennas

    The gains and losses of typical antennas are Antenna Gain (dBi) Dipole Collinear 5 or 8 Directional 10 - 28 Cable type Loss (dB per 10 m / 30 ft) RG58 Cellfoil RG213 LDF4-50 -1.5 The net gain of the antenna/cable configuration is determined by adding the antenna gain and the cable loss.

  • Page 15: Directional Antennas

    30 cm minimum COLINEAR ANTENNA WEATHE RPROOF CONNECTORS WITH SURGE “3M 23” TAPE ARRESTOR (OPTIONAL) COAXIAL CABLE STRESS RELIEF LOOP TX/RX MAST PROVIDE GOOD GROUND 400E CONNECTION TO MAST, MODULE EARTH STAKE AND SURGE IF GROUND ARRESTOR CONDITIONS ARE POOR, INSTALL MORE THAN ONE STAKE INSTALL AERIAL ABOVE...

  • Page 16: Power Supply

    Power Supply The XYR 400E module can be powered from a 9 - 30VDC power supply. The power supply should be rated at 1 Amp. The positive side of the supply must not be connected to earth. The supply negative is connected to the unit case internally. The DC supply may be a floating supply or negatively grounded.

  • Page 17: Rs485 Serial Port

    Ring indicator - 2.4.2 RS485 Serial Port The RS485 port provides for communication between the XYR 400E unit and its host device using a multi-drop cable. Up to 32 devices may be connected in each multi-drop network. As the RS485 communication medium is shared, only one of the units on the RS485 cable may send data at any one time.
  • Page 18 HOST XYR 400E HOST RS485 CONNECTIONS HOST HOST XYR 400E 120Ω Ω RS485 CONNECTION USING TERMINATING RESISTOR Version 1 XYR400E Ethernet Modem 5/1/08...

  • Page 19: Discrete (Digital) Input/Output

    Discrete (Digital) Input/Output The XYR 400E has one on-board discrete/digital I/O channel. This channel can act as either a discrete input or discrete output. It can be monitored, or set remotely, or alternatively used to output a communications alarm status.
  • Page 20 attempt to establish a link with an Access Point whose beacon indicates a matching SSID. Access Points do not initiate link establishment. “Client” Start-up When a Client powers up, it scans for beacons from Access Points. While a link is not established, the Client cyclically scans all available channels for a suitable Access Point.

  • Page 21: Selecting A Channel

    Other conditions indicating a fault are described in Chapter Six Troubleshooting. Selecting a Channel The XYR 400E conforms to the IEEE 802.11 Wireless LAN specification. The XYR 400E supports 11 radio channels, each 5MHz wide, in the range 2412MHz to 2462MHz. Only one of these channels is used for a connection.
  • Page 22 is established. Although each channel is only 5MHz wide, the radio transmission is a lot wider. Hence the channels overlap. The following diagram shows the RF energy distribution for a WiFi transmission: f-33 f-22 f-11 f+11 f+22 f+33 RF power distribution in a WiFi transmission with channel central frequency, f Most of the energy is in a central 22 MHz wide “lobe”, centred around the channel frequency, however there are also side-lobes extending either side.

  • Page 23: Default Configuration

    192.168.0.1XX where XX are the last two digits of the serial number (check the label on the back of the module). The second method requires setting an IP address in the XYR 400E such that it is accessible on your network without having to change your network settings.
  • Page 24 • Power up the XYR 400E module. • Open “Network Settings” on your PC under Control Panel. The following description is for Windows XP - earlier Windows operating systems have similar settings. • Open “Properties” of Local Area Connection. • Select Internet Protocol (TCP/IP) and click on Properties.
  • Page 25 Server for local addresses. This option may be modified by opening Tools -> Internet Options - > Connections Tab -> LAN Settings->Proxy Server -> bypass proxy for local addresses. • Enter the default IP address for the XYR 400E http://192.168.0.1XX where XX is the last two digits of the serial number •...

  • Page 26: Set Xyr 400E To Same Network As Pc

    IP address on your network, the gateway IP address, and network mask. a) Switch Factory Default dip-switch on XYR 400E to SETUP position. b) Connect the RS232 port on the XYR 400E to the RS232 port on the PC using a “straight- through” serial cable.
  • Page 27 This may be performed with the command: bgw <Type the gateway IP address> h) Choose an IP address for the XYR 400E being upgraded. This IP address must be on the same network as the computer you have connected the Ethernet cable to. This may be performed with the command: bip <Type the IP address>...

  • Page 28: Network Configuration

    Ethernet device(s) – before connecting to an existing LAN consult the network administrator. A system of XYR 400E’s must have at least one Access Point acting as a master to one or more Clients. All XYR 400E’s to be configured as part of the same wireless network should be given the same System Address (SSID) and Radio Encryption settings.
  • Page 29 IP address you require. Wireless IP Address The IP address of the XYR 400E on the wireless port. If the unit is configured as a bridge this address will be the same as the Ethernet IP address.

  • Page 30: Ethernet Data

    These are the keys used to encrypt radio data to protect data from unwanted eavesdroppers when WEP Encryption is selected. These keys should be the same for all XYR 400E units in the same system. One of the four keys may be selected as the default key, and is used to encrypt transmitted messages from the configured unit.

  • Page 31: Normal Operation

    Repeaters configuration page. When 3-address mode is used it is not possible for a XYR 400E client to transmit over the radio link the MAC address of any device connected to its wired Ethernet port. Therefore, the XYR 400E client must act as a proxy for devices lying on its wired Ethernet port, and use its own MAC address on their behalf.

  • Page 32: Radio Configuration

    4-address mode should also be used if the bridge Spanning Tree Protocol is required. When a XYR 400E client/station uses 4-address mode any Access Point that it is to communicate with must also be configured for 4-address mode.
  • Page 33 Power Level The RF power level is shown in this field. This value is read only and cannot be altered. Data Rate The radio baud rate in Mega (million) bits per second (Mbps) for point to point radio transmissions. The default value is Auto. Basic Rate The radio baud rate in Mega (million) bits per second (Mbps) for multicast messages and management frames.

  • Page 34: Spanning Tree Algorithm / Redundancy

    The intention is to reduce traffic that the XYR 400E must handle, by placing it at the branch level in the network tree. As a branch, the XYR 400E needs only pass traffic to devices that are its “leaves”.

  • Page 35: Multiple Ap Repeater Mesh Network

    Alternatively, fixed AP to AP links can be configured for optimized throughput. WDS Access Points require IEEE802.11 4-address mode. 4-address mode may also be used by XYR 400E clients when Ethernet protocols other than IP are to be used – see section “3.7 Normal Operation” for more details.
  • Page 36 inherited from the default interface. Note that when WPA is required with a mesh network, the same SSID must be used for each Access Point. Alternatively the list of possible allowed Access Points (by SSID) and their corresponding passphrases must be specified - since WPA Pre-Shared Keys are derived from both passphrase and SSID.
  • Page 37 Access Points with the same SSID. Finally, in this example we demonstrate the flexibility of the XYR 400E by specifying different Encryption on only one of the WDS links. In the example below, 4 Access Points (A, B, C, and D) form a mesh network using only WDS bridge interfaces.
  • Page 38 An example of using WDS router interfaces to achieve a similar physical topology to the WDS bridge example discussed earlier is illustrated below. In both examples, there are four WDS Access points each with the possibility of having their own client/stations associated. In both examples A, B, C, and D can all exchange data with each other.
  • Page 39 A consequence of using a different network address for the WDS link between unit A and B, is that we now need to configure a routing rule at units A and B so that the XYR 400E can determine where to send traffic destined for the respective network addresses of A and B. For example, if unit B receives traffic destined for network 192.168.0.x (i.e.
  • Page 40 B, therefore we wish to have the WDS interface link to unit D bridged with the default interface. Because we don’t specify a router IP address for the third entry the XYR 400E automatically bridges this interface with the default wireless interface.
  • Page 41 Only attempt to establish WDS links with Access Points identified in the list. Maximum WDS connections Each XYR 400E Access Point supports a maximum of 6 WDS links to this device direct to other Access Points. However the maximum may be reduced –...

  • Page 42: Routing Rules

    3.11 Routing Rules When a XYR 400E receives an IP frame that is destined for an IP address on a different network, it checks if the network address matches the network address of one of its own interfaces (i.e. hard wired Ethernet, or wireless Ethernet, or WDS) and forwards the frame appropriately.
  • Page 43 The Routing Rules configuration page can be accessed by selecting the “Routing” link on any of the configuration web pages. Up to 30 routing rules may be added to each XYR 400E. The table below summarizes the configurable parameters of a routing rule.
  • Page 44 Version 1 XYR400E Ethernet Modem 5/1/08...

  • Page 45: Wireless Message Filtering

    The XYR 400E has a filtering feature to help reduce unnecessary wireless transmissions and enhance security. The XYR 400E may be configured to reject or accept messages to and from certain Addresses. To accept wireless messages from particular devices a “Whitelist” of Addresses must be made.
  • Page 46 If radio links are chained together to form a radio backbone, it is also important to consider the operation of the Layer 3 Transparent Bridge (Refer Section 3.7). A XYR 400E Client will act as a MAC Address translator, as it acts as a MAC address proxy on behalf of devices connected to its wired Ethernet port.

  • Page 47: Serial Port Configuration

    Serial Gateway, and Modbus TCP to RTU Gateway. 3.13.1 RS-232 PPP Server The XYR 400E can be used as a PPP Server to connect the wireless Ethernet system to serial devices via the RS232 or RS485 serial ports. PPP Server enables a network connection to the XYR 400E over a serial cable. This is much like dial up internet.
  • Page 48 IP address set for the desired port. A process called “Proxy ARP” is used to make the device visible on the network. In this process, the XYR 400E pretends that it holds the IP address on the network, and responds on behalf of the remote device.
  • Page 49 2. On the New Connection Wizard, click Next 3. Set up an advanced connection 4. Connect directly to another computer XYR400E Ethernet Modem Version 1 5/1/08...
  • Page 50 Set PC as guest 6. Set Computer Name 7. Select a COM port 8. Select availability 9. Click Finish 10. Select properties of this new connection by right clicking on connection. Version 1 XYR400E Ethernet Modem 5/1/08...
  • Page 51 XYR 400E. 17. Ensure both the username and the password are entered exactly as configured in XYR 400E. (When booted in SETUP mode, the PPP server has username “user” and password “user”.)

  • Page 52: Serial Gateway

    Some of the possible Serial Gateway topologies are illustrated below. As can be seen, it is possible for serial data from a XYR 400E to be transferred to one or more XYR 400E serial ports, or to be encapsulated within a TCP/IP socket for availability on an Ethernet network. Conversely, data encapsulated in a TCP/IP socket can be reproduced at a XYR 400E serial port.
  • Page 53 PC. Alternatively the program telnet may be used to connect to a serial port on the XYR 400E. The telnet command used should be: TELNET [IP address] [Listen Port] eg. TELNET 192.168.0.155 23 where the IP address is 192.168.0.155 and Listen Port is 23.

  • Page 54: Modbus Tcp To Rtu Gateway

    The above example demonstrates how a Modbus/TCP Client (Master) can connect to one or more Modbus RTU (i.e serial) Slaves. In this example the XYR 400E Access Point is configured with the “RS232 Modbus/TCP to RTU Gateway” enabled. Once enabled, the gateway converts the Modbus/TCP queries received from the Master into Modbus RTU queries and forwards these over the RS232 port to the Slave.

  • Page 55: Digital Input/Output

    Modbus TCP or RTU devices. The layout of the XYR 400E I/O Registers is summarized in the table below. Each register is internally saved as a 16 bit value. A Modbus transaction may access the entire 16 bit value of any register, or alternatively the most significant bit of a register may be accessed as a discrete value.
  • Page 56 (described below). The Modbus TCP Client may also poll Modbus RTU (i.e. serial) devices connected to either the local serial port or a remote XYR 400E serial port by enabling the Modbus TCP to RTU gateway at the corresponding serial port (see section “3.13.3 Modbus TCP to RTU Gateway”).
  • Page 57 An example of the Modbus functionality of the XYR 400E is illustrated below. In this example the status of the onboard digital input at C will be reflected at the onboard digital output at B. Also, 8 I/O registers from Modbus serial device D will be transferred to A.
  • Page 58 Gateway is to route the message out the serial port to unit A. Since the XYR 400E supports Modbus TCP Client and Server simultaneously, the Modbus TCP Server for unit B above could also be enabled. This would allow one (or more) external Modbus TCP Clients anywhere on the extended wired or wireless network to connect to unit B and monitor the status of the I/O registers –...
  • Page 59 The configurable Modbus I/O transfer options are summarized in the tables below. Modbus TCP Configuration: Enable Modbus TCP Server Check this box to enable the onboard Modbus TCP Server. All Modbus (Slave) TCP connections to the module IP Address and specified Modbus Server Device ID will be routed to the onboard I/O registers.

  • Page 60: Module Information Configuration

    Module Information Webpage Fields This configuration page is primarily for information purposes. With the exception of the password, the information entered here is displayed on the root webpage of the XYR 400E. Password When changing the password on this screen, it will be sent unencrypted over any wired network.

  • Page 61: Configuration Examples

    Configuration Examples Setting a XYR 400E to Factory Default Settings Access configuration webpages of XYR 400E. Refer section Accessing Configuration inside a module for the first time , or Modifying an existing configuration . 1. Click on System Tools Menu Item 2.
  • Page 62 Set dipswitch to SETUP c) Connect straight through serial cable to XYR 400E and power up unit. d) When prompted, strike the Enter key to abort automatic boot e) Set IP address of XYR 400E to 192.168.0.200 with command bip 192.168.0.200 Set netmask of XYR 400E to 192.168.0.200 with command bnm 255.255.255.0...

  • Page 63: Connecting Two Separate Networks Together

    Network B. On PCs, this may be achieved with the MS-DOS command ROUTE. For this example use: ROUTE ADD 169.254.102.0 MASK 255.255.255.0 192.168.0.200 Network B Configuration All devices on Network B should be configured so their gateway IP address is that of the XYR 400E Access Point as 169.254.102.54 Access Point Configuration •...

  • Page 64: Extending Range Of A Network With A Repeater Hop

    Set dipswitch to RUN. Click on button Save to Flash and Reset. Webpage will display that message indicating details are being written to flash. Wait for XYR 400E to reboot before removing power. Enter a System Generator String Client Configuration...

  • Page 65: Chapter Four Diagnostics

    Chapter Four DIAGNOSTICS Diagnostics Chart LED Indicator Condition Meaning GREEN Normal Operation Supply voltage too low. Radio RX GREEN flash Radio receiving data Radio TX Flash Radio Transmitting Radio LINK On when a radio communications link is established Radio LINK Communications failure or radio link not established Link Established on Ethernet port...

  • Page 66: Diagnostic Information Available

    Diagnostic Information Available 4.2.1 Connectivity The Connectivity webpage at an Access Point lists all Clients with which it is associated. The page also indicates whether the encryption scheme has been authorized at the Access Point. A XYR 400E will fail to be authorized if the encryption keys are incorrect. The received signal strength, background noise, and radio data rate is listed for each Client or Access Point by their MAC Address.

  • Page 67: Monitor Communications

    4.2.2 Monitor Communications To monitor radio communications, it is necessary to configure the Operating Mode under “Network” as MONITOR. When in the MONITOR mode, the “Monitor Communications” function displays a continuous list of transmissions that are being received. As Beacon messages occur very frequently, they have been filtered out from the Monitor Communications display for convenience.

  • Page 68: Statistics

    4.2.3 Statistics The Statistics webpage is used for advanced debugging of XYR 400E. This webpage details the state of the XYR 400E and its performance in the system. 4.2.4 Network Traffic Analysis There are many devices and PC programs that will analyse performance of an Ethernet network.

  • Page 69: Utilities

    This command would be written as Ping 192.168.123.123 then Enter to send the ping command. The PC will reply with an acknowledgement of your command and if your XYR 400E is correctly configured your reply will look something like this.
  • Page 70 This -t command is used to repeatedly ping the specified node in the network, to cancel use “Ctrl – C” A good test for the network once it is first set up is to use PING repeatedly from one PC’s IP address to the other PC’s IP address.

  • Page 71: Ipconfig

    4.4.2 IPCONFIG IPCONFIG can be used to show your current TCP/IP information, including your address, DNS server addresses, adapter type and so on. In the above example ipconfig was entered in the command prompt. The reply back shows the PC’s IP address, Subnet mask and the gateway it is connected to. Other ipconfig commands will return back more information.

  • Page 72: Route

    XYR 400E refer to Section 1.1 The XYR 400E can only accept 1 Routing table. That is it can only accept one router per network of radios. On the Router radio network PC a routing rule needs to entered to allow access between Network A and Network B.
  • Page 73 In the Network A PC a routing rule is to be set. This will allow Network A & B to have access to each other. This is entered under cmd prompt. Route ADD 192.168.2.0 MASK 255.255.255.0 192.168.0.191 This says access everything on network B (192.168.2.0) with the Mask of 255.255.255.0 on Network A via the Ethernet IP Interface 192.168.0.191 IP Address 192.168.2.0 will allow everything on this network to be shared by the router.

  • Page 74: Chapter Five Specifications

    Chapter Five SPECIFICATIONS General EN 300 683 FCC Part 90 specification Radio EN 300 328 FCC Part 15.247, RSS 210 specification Housing 114 x 140 x 30mm Powder-coated, extruded aluminum 4.5 x 5.5 x 1.2 inch DIN rail mount Terminal blocks Removable Suitable for 12 gauge (2.5sqmm) conductors...
  • Page 75 Serial Ports RS232 Port DB9 female DCE RTS/CTS/DTR/DCD hardware signals provided RS485 Port 2 pin terminal block Max distance 4000’ / 1.2 km Data rate (bit/sec) 1200, 2400, 4800, 9600, 14400, 7 or 8 data bits, Stop/start/parity bits - configurable 19200, 38400, 57600, 76800, configurable 115200...

  • Page 76: Appendix A Firmware Upgrade

    Appendix A FIRMWARE UPGRADE Determine which firmware version is present in the module to be upgraded by viewing the index webpage of the module. Firmware versions v1.21 and later may be upgraded via the configuration web pages. This upgrade can be done locally with a PC connected directly to the module, or remotely over a working radio link.
  • Page 77 5. There are two options: a. The “Save to Flash and Reset” button may be clicked, to initiate a reset immediately after a successful firmware upgrade so that the new firmware is run. b. Alternatively, Click “Save to Flash” button to just program the new firmware to the unit.
  • Page 78 7. Firmware upgrade will proceed, and should take about 1 minute if performed locally. If performed over a radio link, the upgrade may take longer, depending upon the quality of the radio link, and the amount of traffic on the network. During the upgrade, the webpage shows a progress bar at the bottom right side of the browser window.
  • Page 79 4. Ensure your PC network settings have a Subnet Mask of 255.255.255.0. This can be easily checked using DOS command IPCONFIG. 5. Extract FlashUpdate program, and start the program. 6. If you are running Windows firewall you may be prompted with the following message. Select Unblock so that FlashUpdate program may operate.
  • Page 80 11. Select Server Interface in the FlashUpdate program. (IP address of PC connected to which can be found from step 4 above) 12. Click on Upgrade button in FlashUpdate program. 13. Follow instructions from confirmation window. 14. Click OK, Power down module, wait approximately 1 second, and power up module. This entire step must be accomplished within 30 seconds of completing the previous step.
  • Page 81 15. Programming will commence… 16. If programming was successful, a dialog box is displayed showing this. 17. Switch dipswitch to RUN position and cycle power for normal operation. XYR400E Ethernet Modem Version 1 5/1/08...

  • Page 82: Appendix B Glossary

    Appendix B GLOSSARY Acknowledgment. Access point An access point is the connection that ties wireless communication devices into a network. Also known as a base station, the access point is usually connected to a wired network. Antenna Gain Antennae don't increase the transmission power, but focus the signal more. So instead of transmitting in every direction (including the sky and ground) antenna focus the signal usually either more horizontally or in one particular direction.
  • Page 83 a collision and retransmit after a random time delay. DHCP A utility that enables a server to dynamically assign IP addresses from a predefined list and limit their time of use so that they can be reassigned. Without DHCP, an IT Manager would have to manually enter in all the IP addresses of all the computers on the network.
  • Page 84 mode whereby PCs communicate directly with each other, clients set in Infrastructure Mode all pass data through a central AP. The AP not only mediates wireless network traffic in the immediate neighborhood, but also provides communication with the wired network. See Ad-Hoc and AP. The term used to describe any operation, program or device that transfers data to or from a computer.
  • Page 85 ISO Network A network model developed by the International Standards Organization (ISO) Model that consists of seven different levels, or layers. By standardizing these layers, and the interfaces in between, different portions of a given protocol can be modified or changed as technologies advance or systems requirements are altered.
  • Page 86 Proxy server Used in larger companies and organizations to improve network operations and security, a proxy server is able to prevent direct communication between two or more networks. The proxy server forwards allowable data requests to remote servers and/or responds to data requests directly from stored remote server data. RJ-45 Standard connectors used in Ethernet networks.
  • Page 87 TCP/IP The underlying technology behind the Internet and communications between computers in a network. The first part, TCP, is the transport part, which matches the size of the messages on either end and guarantees that the correct message has been received. The IP part is the user's computer address on a network. Every computer in a TCP/IP network has its own IP address that is either dynamically assigned at startup or permanently assigned.

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