Comtrend Corporation CT-520 User Manual
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Comtrend Corporation CT-520 User Manual

Shdsl router
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CT-520
SHDSL Router
User's Manual
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Version 3.52_5
11-27-2002
261014-028
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Summary of Contents for Comtrend Corporation CT-520

  • Page 1 CT-520 SHDSL Router User’s Manual Version 3.52_5 11-27-2002 261014-028...
  • Page 2 CT-520 SHDSL router. Copyright Copyright© 2002 Comtrend Corporation. All rights reserved. The content of this manual is subject to change without notice. The information and messages contained herein are proprietary to Comtrend Corporation. No part of this manual may be translated, transcribed, reproduced, in any form, or by any means without prior written permission by Comtrend Corporation.

  • Page 3: Table Of Contents

    CHAPTER 1 OVERVIEW...............1 Application..................1 Faceplate LED Indicators ..............2 CHAPTER 2 INSTALLATION ..............3 Preparing for Hardware Installation ........... 3 Rear-panel Connections ..............4 CHAPTER 3 WEB-BASED ACCESS ............5 Login .................... 5 Web Page Layout ................7 Password Setup ................8 Write System Configurations............
  • Page 4 CHAPTER 9 NAT ................35 Multiple to One ................36 One to One NAT................37 Multi-NAT ..................38 Virtual Server................40 CHAPTER 10 DHCP ................41 10.1 DHCP Server ................41 10.2 DHCP Relay ................42 CHAPTER 11 DNS PROXY..............43 CHAPTER 12 IGMP ................44 CHAPTER 13 MAINTENANCE AND DIAGNOSTICS ......46...
  • Page 5 17.2 Telnet Access................70 APPENDIX A: SPECIFICATIONS ............71 APPENDIX B - PIN ASSIGNMENTS ............74 GLOSSARY ................75...

  • Page 6: Chapter 1 Overview

    CHAPTER 1 Overview The SHDSL router satisfies the needs of multiple users in small/home offices and remote/branch offices. It provides symmetrical transmission speeds of up to 2.3 Mbps through a SHDSL connection, over one ordinary telephone line. In addition, it supports up to 16 virtual concurrent connections to multiple destinations. The SHDSL router can be used for variety of applications, including video conferencing, remote training, e-commerce, and other multimedia applications.

  • Page 7: Faceplate Led Indicators

    1.2 Faceplate LED Indicators Color Mode Function POWER Green AC power input is supplied to this unit Power is not connected ALERT Normal status An alarm is occurring Flash Software downloading or self-testing Green Transmit data or receive data over Ethernet link No data transmitted or received over the Ethernet link Yellow On Collision occurs over Ethernet...

  • Page 8: Chapter 2 Installation

    CHAPTER 2 Installation 2.1 Preparing for Hardware Installation The following equipment may be necessary to install the router: AC power adapter A power adapter is shipped with the router. LAN connection cable Use an RJ45 cable to connect the device to a PC or Hub. RJ11 cable An RJ11 cable is needed to connect to the LINE port to the wall outlet.

  • Page 9: Rear-Panel Connections

    2.2 Rear-panel Connections Step 1 DSL connection Connect the supplied telephone cable to the port marked LINE at the back of the SHDSL router. Connect the other end of the cable to your telephone-line wall outlet. Ensure your computer is turned on before you connect the DSL line to the router.

  • Page 10: Chapter 3 Web-Based Access

    CHAPTER 3 Web-based Access This section describes how to manage the router via the Web browser from the remote end. The Web page is best read with a display resolution of 1024 x 768. To change the resolution you can go to the Microsoft Windows control panel and click on the Display icon, and change the display settings.
  • Page 11 STEP 4: You will be prompted to enter your user name and password. Type your password, or if the password was not changed, type the default passwords. The default ADMINISTRATOR user name and password are root. STEP 5: After successfully logging in, you will reach the main configuration page. The left hand side has a menu and the right side is blank.

  • Page 12: Web

    3.2 Web Page Layout On each Web page, there are two areas. Menu Bar: On the left side of the Web page is the menu bar. It is divided into two parts: Basic and Advanced. The Basic menu bar sets up the device for quick setup.

  • Page 13: Password Setup

    3.3 Password Setup There are two types of access privileges. A system ADMINISTRATOR is the only person that can configure, change parameters, monitor, and read the performance and status of the system. A USER can only monitor and read the status of the system.
  • Page 14 Terminal Type: When the router is connected to the DSLAM, select CPE. When the router is connect to a router for point to point application, one of the devices should be set to CO with the other set to CPE. The default setting is CPE.

  • Page 15: Write System Configurations

    3.4 Write System Configurations The new parameters can function immediately without being saved to the flash memory. To use these parameters after you restart the router, you must save them to the flash memory. To write the configurations, click the Save & Reboot button. Click the Save button on the main screen.

  • Page 16: Load Factory Default Values

    3.5 Load Factory Default Values Caution! If you reset your device to the factory default, any changes to parameters will be lost and all parameters will revert to their default values. To retrieve the factory default settings, STEP 1: Click Erase & Reboot on the Basic menu bar. STEP 2: Click Erase and Reboot respectively.

  • Page 17: Chapter 4 Configuring The Lan Interface

    CHAPTER 4 Configuring the LAN Interface To set-up the Ethernet Interface, follow the descriptions below: STEP 1: Click LAN Setup on the Basic Menu bar. STEP 2: Enter the new IP address and Subnet, and click Apply to display the following screen.
  • Page 18 STEP 3: You can click the Change & Reboot button to use the new IP address and reset the device immediately. This doesn’t need the save action. Alternatively, you can click the Change button to use the new IP address but you need to save the new setting before you reset the router.

  • Page 19: Chapter 5 Configuring The Wan Interface

    CHAPTER 5 Configuring the WAN Interface Click WAN Setup on the Basic menu bar and configure the VC to RFC1483 Bridged, RFC1483 Routed, PPPoE or PPPoA.

  • Page 20: Rfc-1483 Bridged Mode

    5.1.1 RFC-1483 Bridged Mode To configure a WAN interface for Bridged (RFC-1483 Bridged) mode, complete the following steps: STEP 1: Click WAN Setup on the Basic menu bar. STEP 2: Click RFC-1483 Bridged Mode STEP 3: Enter values for the following fields: Enter a value for the vitual path identifier Enter a value for the virtual channel identifier LLCEncapsulation:...

  • Page 21: Rfc-1483 Routed

    5.1.2 RFC-1483 Routed To configure a WAN interface for RFC-1483 Routed, complete the following steps: STEP 1: Click WAN Setup on the Basic menu bar. STEP 2: Click RFC-1483 Routed STEP 3: Enter values for the following fields: VPI/VCI Enter VPI (range:0-255) and VCI (Range:0-65535) AAL5 Encapsulation LLC and VCMUX...

  • Page 22: Pppoa

    5.1.3 PPPoA When a VC is configured for PPPoA, the router will auto-detect the Authentication code (pap or chap), and the NAPT function will be enabled automatically. STEP 1: Click WAN Setup on the Basic menu bar. STEP 2: Click PPPoA STEP 3: Enter values for the following fields: Enter a value for the virtual path identifier (range:0-255) Enter a value for the virtual channel identifier (Range:0-65535)
  • Page 23 To modify the VC, click a VC from the Current ATM PVC List to display the parameters of the VC. Change its parameters and click the Modify button.

  • Page 24: Pppoe

    5.1.4 PPPoE When a VC is set in the PPPoA, the router will auto-detect the Authentication code (pap or chap). The NAPT and DHCP server functions will be enabled automatically. STEP 1: Click WAN Setup on the Basic menu bar STEP 2: Click PPPoE STEP 3: Enter values for the following parameters: (range:0-255)
  • Page 25 STEP 4: Click the Add button. The new VC is added in the Current ATM PVC List on the bottom screen. To modify the VC, click a VC from the Current ATM PVC List to display the parameters of the VC. Change its parameters and click the Modify button.

  • Page 26: Vc Data Flow Control

    5.1.5 VC Data Flow Control To set-up the flow control parameters, such as AAL5 encapsulation, QOS, Peak Cell Rate, Sustainable Cell Rate, and Burst Tolerance, follow the steps below: 1. Click WAN Configure on the Advanced menu bar, and click the VCC tab on the main menu.
  • Page 27 2. Tick a VC in the Index field and click the modify button to configure the VC’s flow control parameters. Parameters The Virtual Path Identifier (VPI) is part of the cell header for ATM cells that are transferred over this connection. The VPI value ranges between 0 and 255.
  • Page 28 for emulating circuit switching. The cell rate is constant with time. CBR applications are very sensitive to cell-delay variation. Examples of applications that can use CBR are telephone traffic (i.e., nx64 kbps), videoconferencing, and television. VBR - Variable Bit Rate. A certain rate is specified for the flow of information.

  • Page 29: Setting Up An Isp

    5.1.6 Setting up an ISP The router supports connection to up to 16 ISPs. Each ATM Interface can connect to an ISP. To set-up or configure the connection parameters to ISP, complete the following steps: 1. Click WAN Configure on the Advanced menu bar. Click the ISP tab on the main screen.
  • Page 30 4.click OK to complete the settings.

  • Page 31: Chapter 6 Bridging

    CHAPTER 6 Bridging Click Bridging on the Advanced menu bar to set-up the static bridging and Spanning Tree protocol (STP) functions. 6.1 Spanning Tree Protocol The STP function is disabled by factory default. To enable it, click Enable in the Spanning Tree field and configure the interfaces on the screen.

  • Page 32: Static Bridging

    6.2 Static Bridging To access the Static Bridging screen go to the ADVANCED menu and click on Bridging. Click the Static tab to configure, modify, and delete the static bridging functions. The parameters are as follows: MAC Address: This is the Mac address of the PC. Each PC has a different Mac Address such as 0a:01:1a:11:00:0b.

  • Page 33: Chapter 7 Routing

    CHAPTER 7 Routing This chapter describes how to set-up the static routes and RIP. Click Routing Setup from the Basic menu bar to configure the routing functions. 7.1 Static Route The router has no default static route. After an RFC1483-routed VC is created, a static route as follows will be created.
  • Page 34 Add: To add a static route complete the following steps: STEP 1: To add a static type the Destination Network ID, subnet mask, and if appropriate enter values for the Next Hop IP and metric. The next hop IP address is also called the default gateway. The metric represents the cost of the routing path.

  • Page 35: Set-Up The Rip Function

    7.2 Set-up the RIP function To enable the RIP function (Routing Information Protocol. The protocol governing the exchange of routing information), complete the following steps: STEP 1: Click Routing Setup from the Basic menu bar STEP 2: Select On in the Rip Status field. STEP 3: Select a RIP Version (Version 1 or Version 2) from the Version field.
  • Page 36 the Authentication Code field to assign a password. Poison Reverse: Enabled: to enable the Poison Reverse Disabled: to enable the Splitting Horizon The default setting of poison reverse parameter is Enabled. It means the router adopts the split horizon with poison reverse scheme to avoid routing loop problems.

  • Page 37: Displaying The Routing Table

    7.3 Displaying the Routing Table To display the routing table, you can enter either of the following screens: BASIC/ROUTING SETUP/ROTUING TABLE screen Advance/Utilities/Routing Table The following routing table appears after clicking Basic>Routing Setup>Routing Table.

  • Page 38: Chapter 8 Snmp

    CHAPTER 8 SNMP The default setting of the SNMP function is disabled. SNMP is a software entity that responds to information and action request messages sent by a network management station. The messages exchanged enable you to access and manage objects in an active or inactive (stored) MIB on a particular router.

  • Page 39: Disable Snmp

    8.2 Disable SNMP Click SNMP on the Advanced menu bar and click the Modify button at the bottom of the screen. Choose Disable in the SNMP Service field and click Apply to submit the setting.

  • Page 40: Chapter 9 Nat

    CHAPTER 9 Network Address Translation (NAT or NAPT) is a transparent routing function that translates a Private IP address on a LAN into a Public address that can be used in a public network. Port Address Translation (PAT) is a form of NAT that maps multiple Private IP addresses to a single Public IP address.

  • Page 41: Multiple To One

    In PPPoE or PPPoA mode, the NAT function is automatically enabled. In RFC1483 Routed mode, to enable the NAT, you must tick the Enable NAPT item on the WAN Setup screen. The following pages describe how to set-up a virtual server (Redirect port) and different types of NAT.

  • Page 42: One To One Nat

    9.2 One to One NAT One-to-one NAT maps a private IP address to a public IP address, such as 192.168.1.10 to 10.1.1.34. Click NAPT on the Advanced menu bar and click the NAT/PAT tab to access the NAT/PAT Configuration screen. Follow the steps below: STEP 1: Tick Fixed-NAT.

  • Page 43: Multi-Nat

    9.3 Multi-NAT Multi-NAT requires a set of continuous private IP addresses to a set of continuous public IP addresses. There are two types of Multi-NAT to translate the private IP addresses to public IP addresses. One condition is that each public IP address can map an individual private IP address.
  • Page 44 STEP 2: Click the Add button. When the private IP addresses are more than the public IP addresses This application can be used when the public IP addresses are not enough that each private IP address can be mapped to each public IP address. The following parameters are used: Start Private IP address- End Private IP Address: 192.168.1.3- 192.168.1.22...

  • Page 45: Virtual Server

    9.4 Virtual Server If you want to set-up Internet servers, such as Email server, web server, or ftp server on the virtual LAN when PAT is enabled, you should register the servers with the router first to allow Internet users to access the service via the WAN interface of router.

  • Page 46: Chapter 10 Dhcp

    CHAPTER 10 DHCP The router can be set as a DHCP server or a DHCP relay. The former acts like an IP address pool. Upon power on, the PCs on the same domain will request an available IP address from the IP address pool of DHCP server. The Dynamic Host Configuration Protocol (DHCP) provides a centralized approach to allocating IP addresses.

  • Page 47: Dhcp Relay

    To configure the router as a DHCP server, click DHCP on the Advanced menu bar. Click Enable in the DHCP Server field, and fill out the parameters. Click Apply to submit the settings. 10.2 DHCP Relay Click DHCP on the Advanced menu bar. On the main screen, click the BOOTP/DHCP Relay tab and configure the following parameters: BOOTP/DHCP Relay: Enable IP Address: This defines the IP address of the remote DHCP server.

  • Page 48: Chapter 11 Dns Proxy

    CHAPTER 11 DNS Proxy A Domain Name Server (DNS) provides an IP address to a host computer for an applied Domain Name. The router supports the DNS proxy feature, which receives and attempts to find an entry in its local tables, and when one is not found, it forwards the request to a remote server.

  • Page 49: Chapter 12 Igmp

    CHAPTER 12 IGMP IGMP (Internet Group Membership Protocol) is a protocol used by IP hosts to report their multicast group memberships to any immediately neighboring multicast routers. STEP 1: Add a VC and set it to RFC 1483 Routed mode. STEP 2: Click IGMP Proxy on the Advanced menu bar.
  • Page 50 STEP 3: Click Enable and choose the interface ATM1-ATM16 that the router is used to connect to the server. This depends on VC to which interface it is assigned. STEP 4: Click Apply to submit the settings.

  • Page 51: Chapter 13 Maintenance And Diagnostics

    CHAPTER 13 Maintenance and Diagnostics This chapter describes the maintenance such as loopback, PING, software upgrade via TFTP, configuration back and restoration, and the performance monitoring. 13.1.1 Software Upgrade and Configuration Backup /Restoration The router supports TFTP upgrade via Console, Telnet, and Web browser. Via a TFTP server, these tasks can be achieved: upgrade the software, back up the configuration, and retrieve the configurations.
  • Page 52 Note2: If a wrong format of the file us uploaded, a failure message will display during the upgrade. The following is an example of upgrade failure resulting from an incorrect file format. Before performing the TFTP upgrade, run the TFTP software. Click Utilities on the Advanced menu bar.
  • Page 53 After completing the settings, click Apply to perform the function and note the following. After software or homepage upgrades are complete, reboot the device to run the new file. After the configurations are retrieved, also write the configurations to the Flash memory.
  • Page 54 To upload the configurations, check Upload, select Configuration, and click the Apply button to submit the settings.

  • Page 55: Oam Loopback

    13.2 OAM Loopback Click Utilities on the Advanced menu bar, and click the Loopback tab on the main screen. After filling out the following parameters, click Start Loopback to perform the loopback. Flow Type Choose the F5 loopback type. Seg is the segment loopback. It verifies the connection between the router and DSLAM.

  • Page 56: Ping

    13.3 Ping A Ping test is used to verify the status of a network connection after the RIP or static route function is enabled. Ping sends a request message to the host and waits for a return message. This diagnostic function can verify if the remote host is reachable.

  • Page 57: Performance Monitoring

    13.4 Performance Monitoring Click System Statistics on the Advanced menu bar to monitor the interface status and collect the statistics of the TCP/IP. 13.5 System statistics To display the interface statistics, click the Interface tab, located at the top-left of the System Statistics screen. The Interface Statistics page displays statistics for all interfaces.

  • Page 58: Tcp-Ip Statistics

    13.6 TCP-IP statistics To view TCP-IP statistics click on the TCP-IP tab at the top of the System Statistics page. The TCP-IP page displays the IP statistics, UDP statistics, TCP statistics, and ICMP statistics.

  • Page 59: Interface Monitor

    13.7 Interface Monitor Click Interface Monitor on the Advanced menu bar to monitor the transmission status.

  • Page 60: Chapter 14 Application Example

    CHAPTER 14 Application Example 14.1 Adding the Static Route (Web) Click Routing Setup on the Advanced menu bar. The following demonstrates a school application as an example. Location A:10.164.32.9 Netmask:255.255.255.252 Location B:10.164.32.10 Netmask:255.255.255.252 Network of the School :210.240.117.0 Netmask:255.255.255.128 In the above example, add the following static route to the router. 210.240.117.0 Netmask:255.255.255.128 Next hop: 10.164.32.9...
  • Page 61 Enter the parameters of the static route and click the Add button. Click LAN Setup on the Basic men bar. After typing LAN IP 10.164.32.10 and Netmask 255.255.255.252, click Apply to submit the settings.

  • Page 62: Chapter 15 Monitoring The Device

    CHAPTER 15 Monitoring the Device Click Link Status on the Basic menu bar. The Link Status screen has two tabs: SHDSL Status and Performance. SHDSL Status is used to monitor the SHDSL link and Performance is used to monitor SHDSL performance. 15.1 Monitoring the SHDSL Line Click Link Status on the Basic menu bar.

  • Page 63: Performance Statistics

    SNR Margin: Signal-to-Noise Ratio (dB) ES (current 15 min): The cumulative statistics of Errored Seconds, for the current 15 min period ES (current 1 day): The cumulative statistics of Errored Seconds, for the current day. CRC (since reset): The cumulative statistics of seconds, since last reset, when there is a CRC error in the preceding superframe.
  • Page 64 Performance parameters Line Attenuation (dB): Current attenuation SNR Margin: Signal-to-Noise Ratio (dB) CRC (since reset): The cumulative statistics of seconds, since last reset, when there is a CRC error in the preceding superframe ES (since reset): The cumulative statistics of Errored Seconds, since last reset SES (since reset): The cumulative statistics of Severely Errored Seconds, since last reset...

  • Page 65: Chapter 16 Console Access

    CHAPTER 16 Console Access To access the device via the console port the following are required: VT-100 Compatible Terminal This terminal is essential to perform the initial configuration of the router. This is normally a terminal with a VT-100 emulation program, such as Telix or HyperTerminal Edition 5.
  • Page 66 STEP4: After successfully logging in, the main menu will display.

  • Page 67: Keyboard Operations

    16.1.2 Keyboard Operations ↑ The upward arrow key moves the cursor upward in the menu ↓ The cursor moves downward in the menu. ← Returns to the previous menu. If you are in a leaf menu you may need to push first (to save the information) →...
  • Page 68 If you are unable to use the arrow keys, you can use the backup keys to replace them, e.g., Ctrl-W for the Up arrow key. These backup keys also display on the bottom screen. In addition to the arrow keys to move the cursor in the menu, you enter the requested screen by entering the number.
  • Page 69 STEP 2: From the MAIN/ADVANCE menu, press the 2 key and then press the Enter key STEP 3: Press the 2 key, and then press the Enter key in MAIN/ADVANCE/DHCP. STEP 4: Now you have reached MAIN/ADVANCE/DHCP/RELAY.

  • Page 70: Motoring The Shdsl Line Status

    16.1.3 Motoring the SHDSL Line Status Enter MAIN/BASIC/SHDSL to monitor the SHDSL Line status. 16.1.4 Password Setup Enter MAIN/BASIC/SYSTEM to change the passwords.

  • Page 71: Retrieve The Factory Default Settings

    New Administrator Password and Retype Password: Enter the administrator password in the New Administrator Password and confirm the password by retyping the password in the Retype Password field. New User Password and Retype Password: Enter the user password in the New User Password and confirm the password by retyping the password in the Retype Password field.

  • Page 72: Save The Configurations

    16.1.7 Save the Configurations The new parameters can function immediately without being saved to the flash memory. However, to use these parameters after you restart the router, you must save them to the flash memory. To write the configurations, enter MAIN/WRITE and press the Y key. After saving the configurations, you will be prompted if you need to reboot the device.

  • Page 73: Chapter 17 Telnet Access

    CHAPTER 17 Telnet Access This chapter will introduce the command line interface using Telnet. The chapter is divided into two parts. The first part explains how to set the PC and router to the same network segment, the second part explains how to start a Telnet session. 17.1 Setting a Common IP Address To log on to the device using Telnet, your workstation and the router should both...
  • Page 74 You can modify the IP address of your PC by modifying its TCP/IP. Follow the steps below: STEP 1: Enter the TCP/IP screen and change the IP address to the same domain as your device. STEP 2: Click OK to submit the settings.

  • Page 75: Telnet Access

    17.2 Telnet Access To access Telnet to manage your router complete the following steps: STEP 1 Make sure that the router and your Telnet-PC are on the same network segment. STEP 2 Connect the LAN port of the router to Ethernet or PC with an RJ45 cable.

  • Page 76: Appendix A: Specifications

    Appendix A: Specifications WAN interface (one SHDSL port) Item Specifications Encoding scheme TC-PAM Line rate Per ITU-T G.991.2 (G.SHDSL) Data rate N x 64 Kbps, N= 1-36 ATM attributes Item Specifications PPP over AAL5 RFC2364 Multi-protocol over AAL5 RFC-1483 Bridge RFC 1483 Router AAL type AAL5...
  • Page 77 SNMP Telnet Web-based management Configuration backup and restoration Yes LED indicators Power, LAN status, SHDSL status Local interface (One Ethernet port) Item Specifications Standard IEEE 802.3 10Base-T Transparent bridging and learning Routing functions Item Specifications IP static route RIP and RIPv2 Network functions Item Specifications...
  • Page 78 PAP, CHAP Power supply Item Specifications Power source 110 VAC or 220 VAC (50 or 60 Hz) Input voltage 12 to 14 VAC Environmental conditions Item Specifications Operating temperature 0 to 50 degrees Celsius Relative humidity 5% to 90% (non-condensing) Compliance Dimensions Item...

  • Page 79: Appendix B - Pin Assignments

    Appendix B - Pin Assignments Pin number Definition Pin number Definition Note: NC means No connection. Table C-1 Pin Assignments of Console Port Pin number Definition Pin number Definition Transmit data+ 5 Transmit data- 6 Receive data- Receive data+ 7 Note: NC means No connection.

  • Page 80: Glossary

    GLOSSARY 100BaseT: A 100 Mbps Ethernet standard that uses twisted-pair wiring. 10BaseT A 10 Mbps Ethernet standard that uses twisted-pair wiring. address: The symbol (usually numeric) identifying an interface attached to a network. ADSL: An asynchronous form of DSL in which the bandwidth available for downstream connection is significantly larger than for upstream.
  • Page 81 busy: A device’s operational state, when the device is occupied with processing a call. Byte: Eight bits arranged in sequence channel: A bi-directional communications pathway between a host server and a client. CHAP: Challenge-Handshake Authentication Protocol. A PPP protocol to ensure authentication of the connection between two devices.
  • Page 82 errored second: An item in performance measurement report, which pertains to a one second period with one or more errored blocks. Ethernet address: Another name for MAC address. Ethernet: A standard protocol (IEEE 802.3) for a 10-Mb/s baseband local area network (PAT) bus that supports high-speed communication among systems.
  • Page 83 ITU: International Telecommunications Union. The telecommunications agency of the United Nations. kbps: Literally it means Kilobits per second, but usually it is taken to mean 1,024 bits per second. LAN: Local Area Network. A LAN is a A data communications system that lies within a limited spatial area, has a specific user group, and has a specific topology.
  • Page 84 noise: Unwanted interference to a transmitted signal by an outside source. PAP: Password Authentication Protocol. PPP protocol that ensures authentication of the connection between two devices. PAT: Port Address Translation is a form of NAT that maps multiple Private IP addresses to a single Public IP address.
  • Page 85 in the network. RS-232: a low-speed, 25-position, DCE/DTE interface. server: Hardware or software that offers a specific service, such as database management, to a client. SHDSL: Symmetric High Bit Rate Digital Subscriber Loop. A DSL technology that allows symmetrical transmissions over longer distances. Defined by the G991.2 ITU standard. SLA: Service Level Agreement.

  • Page 86: Virtual Circuit

    UNIX: An operating system developed at AT&T Bell Laboratories. upload: To receive a file transmitted over a network. URL: Uniform Resource Locator. An Internet standard addressing protocol for describing the location and access method of a resource on the Internet. USB: Universal Serial Bus.

  • Page 87: Contact Information

    Contact Information Contact by email North America Technical Support: NA.support@comtrendcorp.com International Technical Support: globalsp@comtrendcorp.com Contact by phone North America Office: 1- 949-753-9640 European Office: 34-917080105 Shanghai Office: 86-21-6251-9161 Taipei Office: 886-2-2999-8261...

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