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CTC Union Technologies Co., Ltd. Neihu Technology Park Vienna Technology Center 8F, No. 60 Zhouzi St. Neihu, Taipei, 114 Taiwan ET100A Ethernet WAN Bridge, User Manual Version 2.0 March 21, 2014 Release This manual supports the following models: ET100A Ethernet WAN Bridge (manufactured after March 2014) All specifications subject to change without notice. ...
Table of Contents OVERVIEW......................7 FEATURES ......................7 SPECIFICATIONS ....................8 THEORY OF OPERATION .................. 13 DIP SWITCH SETTING TABLES:................16 WAN PORT PIN ASSIGNMENT................20 CABLE PIN ASSIGNMENTS: ................24 RS‐530 ............24 ABLE CONDUCTOR ROUND TO ...
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ET100A LAN-WAN Bridge Overview The ET100A Network Bridge is a high performance, remote, self‐learning Ethernet bridge. Its compact size and low cost make it ideal for cost‐sensitive bridging applications, or as a LAN extender or segmenter over bit stream type infrastructures. Several selectable synchronous data interfaces, including V.35, RS‐530, RS‐449, X.21, and RS‐232, make this Ethernet Bridge's connection between 10Base‐T and 100Base‐TX LAN and various SYNC data port interfaces convenient. Features Supports raw HDLC, Cisco® HDLC, and PPP encapsulation 10BASE-T/100BASE-TX, Full Duplex or Half Duplex HP Auto-MDI/MDIX detects and corrects crossed cable Automatic address learning, aging and deletion after 5 minutes Forwarding and filtering rate at wire speed with through put latency of 1 frame.
ET100A LAN-WAN Bridge WAN SIDE DB25-Male Interface Select RS-530/449 Serial Port LINK V.35 Tx LED X.21 Line Drivers Rx LED RS-232 SYNC Clock SYNC Source HDLC Ext. clock CONTROLLER ...
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ET100A LAN-WAN Bridge DB25 Male Connector: This connector connects to the appropriate adapter cable for connection to the various supported data interfaces. The ET100A performs in DTE mode and its WAN port connector may be connected directly to a DCE device (such as a modem or DSU/CSU). SYNC LED: Green, where ON indicates protocol is up. If OFF, first make sure physical link is up, then make sure protocol settings match. LINK LED: Green, where ON indicates the presence of CTS / DSR signal on WAN connection. RX LED: Green, on or flashing indicates receiving data on the WAN interface. TX LED: Green, on or flashing indicates transmitting data on the WAN interface. SW1: Configuration setting for the bridge. (Please refer to DIP SW setting table.) SW2: Configuration setting for the bridge. (Please refer to DIP SW setting table.) RJ‐45 Ethernet LAN Port: This is an auto‐MDI/MDIX port for connection to the LAN. ...
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ET100A LAN-WAN Bridge LINK LED: (LAN) Green, indicates the Ethernet has a link to an external device. (10) ACT LED: (LAN) Green, indicates data being received from the LAN connection. (11) ERROR LED: Red, indicates an error condition as follows: ON ‐ System Error Pulse 2 ‐ Configuration error Pulse 3 ‐ WAN receive has CRC errors (12) PWR LED: Green on, when external power adapter is plugged in and AC power is supplied to it. (13) DC 9~12V This jack receives power from the external DC 12V AC power switching adapter. The center pin is positive voltage. ...
ET100A LAN-WAN Bridge Theory of Operation A bridge is used to connect networks locally or remotely such that they appear to the user to be the same network. An Ethernet LAN bridge will connect two LAN segments at the Data Link Layer (ISO Layer 2). At this layer, the MAC (Media Access Control) addresses, are used for low level addressing to send information to devices. The bridge builds tables of MAC addresses for each network segment based on the source and destination addresses of the packets it receives and forwards, then filters the traffic not destined for the remote network. The Ethernet‐WAN bridge will connect two remote Ethernet networks over bit stream interfaces such as that of synchronous modems or DSU/CSUs. One method to do this is to use HDLC, an international standard set by the ISO, a set of protocols for carrying data over a link with error and flow control. Another method uses PPP and a third uses Cisco® HDLC. The ET100A utilizes both Ethernet Bridging and encapsulation to provide a connection between LANs over bit stream architectures. The LAN side of the ET100A receives an Ethernet packet and examines its destination MAC address. If it knows the MAC is on the local network then it simply drops the packet. Otherwise, if it knows the packet destination is on the remote side, or if it cannot be determined because its MAC cannot be found in the table, then it forwards it. During forwarding, the packet is processed for transmission across the WAN link. Here is where the Ethernet packet in encapsulated. ...
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ET100A LAN-WAN Bridge When the HDLC or PPP packet is received on the remote side unit's data port, the packet is checked for transmission errors, then the original Ethernet packet(s) is recovered and sent out the remote's LAN port completing the transmission. Here is the typical application of the ET100A. ET100A/V35 ET100A/V35 Figure 3. Typical application of ET100A LAN‐WAN Bridge. Many times the ET100A is commonly referred to as an Ethernet to V.35, Ethernet to X.21, or Ethernet to Datacom 'converter'. As a sales/marketing term or non‐technical reference, the term is OK. However, from a technical standpoint, the term is a misnomer. The Ethernet is not "converted" to V.35, it is run "over" the V.35 link. Conversion also implies that the interface can work both ways. This is NOT the case for the LAN‐WAN Bridge as the following application shows. ET100A/V35 ET100A/V35 Figure 4. Application NOT ALLOWED for ET100A. ...
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ET100A LAN-WAN Bridge Why does the previous application not work? It won't work because the application requires a bit stream to be encapsulated into Ethernet packets, or into TCP/IP and then Ethernet, for transmission across the LAN. This requires more than just manipulation at the Data Link layer (ISO Layer 2), it requires programming to include all seven layers including the Application layer. Transmitting bit stream or TDM (time division multiplexed) data over Ethernet requires a device such as an IP‐Multiplexer. Please refer to the "Applications" section at the end of this manual for additional application examples. ...
ET100A LAN-WAN Bridge DIP Switch Setting Tables: SW1-1 SW1-2 FUNCTION REMARK HDLC Cisco® HDLC Table 1: Encapsulation Protocol Setting DIP SW1 STATE FUNCTION REMARK WAN CLK: External WAN CLK: Internal Table 2: Clock Source Setting DIP SW1 STATE FUNCTION REMARK CTS/DSR Active DCD always on Table 3: DCD Handshaking Setting ...
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ET100A LAN-WAN Bridge When the ET100A is set to internal WAN clock, SW2‐3 to SW2‐9 provision the data rate. If WAN clock is set external, these are ignored. SW2-3 SW2-4 SW2-5 SW2-6 SW2-7 SW2-8 OFF SW2-8 ON SW2-8 OFF SW2-8 ON SW2-9 OFF SW2-9 OFF SW2-9 ON SW2-9 ON N*64K N*56K HS-1 HS-2 2176K 6272K 128K 112K 2304K 6400K 192K...
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ET100A LAN-WAN Bridge When the ET100A leaves the factory, all DIP switch settings are set to the OFF position. Auto‐negotiation: When this feature is enabled (SW1‐6=OFF), the Speed (SW1‐7) and Duplex (SW1‐8) settings are ignored and are automatically determined from the LAN connection. When this feature is disabled (SW1‐6=ON), the Duplex and Speed settings of the LAN follow the settings of SW1‐7 and ...
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ET100A LAN-WAN Bridge LAN Flow Control: The ET100A LAN port supports IEEE802.3x flow control, which can help to regulate the higher speed LAN traffic that hits the bottle neck of the slower WAN speed. Without flow control, the LAN packets that exceed the WAN speed will be dropped and the resulting timeout caused must be handled by the application layer. LAN Auto Negotiation: The ET100A LAN port supports auto‐negotiation per IEEE802.3u. When auto negotiation is enabled and the LAN port connects to another auto negotiation compliant port, the LAN speed will be auto detected while the Duplex should be negotiated to Full Duplex. When connecting to legacy equipment, it may be necessary to 'force' the speed and Duplex on the LAN port. Care must be taken here to avoid a Duplex Mismatch condition when a 'forced' port connects to an 'auto' port. Without negotiation, an 'auto' port will revert to Half Duplex per the IEEE802.3u standard. A Duplex Mismatch condition could result in extremely poor network performance. WAN Interface Selection: The ET100A has selectable hardware interface circuits. When set to X.21/RS‐530/RS‐449, the logic, clock and handshaking signals all follow RS‐422 electrical (balanced signals). When set to RS‐232, all signals become single ended and follow RS‐232D signal levels. When configured as V.35, the logic and clock signals follow RS‐422 electrical, while handshaking signals are RS‐232 electrical. ...
ET100A LAN-WAN Bridge WAN Port Pin Assignment The following tables give the pin, circuit, function and signal direction as seen on the ET100A's DB25M connector for each of the selectable interfaces. RS‐232 and RS‐530 connections may be made directly. Adapter cables are required to match the physical connectors for V.35 (MB34), X.21 (DB15) and RS‐449 (DB37). a. V.24/RS‐232 INTERFACE PIN ASSIGNMENT CIRCUIT FUNCTION DIRECTION 1 FGND Protective GND AA 2 TD Transmit data OUT BA 3 RD Receive data IN BB 4 RTS Request to send OUT CA 5 CTS Clear to send ...
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ET100A LAN-WAN Bridge b. V.35 INTERFACE PIN ASSIGNMENT CIRCUIT FUNCTION DIRECTION CCITT 1 FGND Protective GND 101 2 TD(A) Xmit data A OUT 103 3 RD(A) Receive data A IN 104 4 RTS Request to send OUT 105 5 CTS Clear to send IN 106 6 DSR Data set ready IN 107 7 ...
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ET100A LAN-WAN Bridge c. RS‐449/RS‐530 INTERFACE PIN ASSIGNMENT CIRCUIT FUNCTION DIRECTION CCITT 1 FGND Protective GND 101 2 SD(A) Xmit data A OUT 103 3 RD(A) Receive data A IN 104 4 RS(A) Request to send A OUT 105 5 CS(A) Clear to send A IN 106 6 DM(A) Data set ready A IN 107 7 ...
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ET100A LAN-WAN Bridge d. X.21 INTERFACE PIN ASSIGNMENT CIRCUIT FUNCTION DIRECTION CCITT 1 FGND Protective GND 101 2 T(A) Xmit data A OUT 103 3 R(A) Receive data A IN 104 4 C(A) Request to send A OUT 105 7 GND Signal ground 102 8 I(A) Data carrier detect A IN 109 ...
V.35 to match the CSU/DSU unit. The CSU/DSU may be set unframed or may be set to use a fraction (n x 56 or n x 64) of the E1 (or T1) line. The CSU/DSU timing is received from the carrier provider's network so the ET100A's timings for Tx and Rx clocks should be set to external. In this configuration, the rate DIP settings of the ET100A are ignored. ...
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ET100A LAN-WAN Bridge APPLICATIONS In the next example, the ET100A is setup to bridge over a PSTN's leased line. The ET100A's speed settings depend upon the speed of the leased line and the settings of the modems. The timing scheme recommended is this application is for the Tx and Rx Clocks of each unit to be set to External while the clocks of the modems are set to Internal for ...
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ET100A LAN-WAN Bridge APPLICATIONS In the following example, the ET100A is paired with a G703/64K interface converter to provide connection over G.703 64Kbps services. If the G.703 transmit and receive clocks are provided by the central carrier, each G703/64K converter will be set to centra‐directional line timing. Both ET100A's will have their Tx / Rx clocks set external. Figure 7: ET100A bridge over G.703 64K services. ...
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CTC Union Technologies Inc Fax:(886)2 27991355 Tel:(886)2 26591021 Attn : Technical Support Department techsupport@ctcu.com From Company: Name: Tel: ( Fax:( MODEL: ET100A ACTIVITY: As attached in DIP switch setting table SYS CONFIGURATION: Question ...
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Technical Inquiry Form MODEL No.: ET100A Please fill in the DIP switches configuration with ' ' marks into the following table. Send it to us by fax, and we will reply to you immediately. Your Setting CTC Suggestion SW NO. DIP...
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