Getting Help

Transmit (XMT) This green LED ﬂashes when the FOT-DF24 transmits data. The LED ﬂash is pulse stretched for viewing effect. The XMT LED is off when the device is active but not transmitting.

Receive (RCV) This yellow LED ﬂashes when the FOT-DF24 receives data from the network. If attached to a repeater, RCV ﬂashes when data passes through the FOT-DF24. The LED is pulse-stretched for viewing effect.

Collision (CLN) This red LED ﬂashes when the transceiver detects a collision condition or a jabber packet on the network. The ﬂash frequency may increase as network trafﬁc increases since more collisions are likely to occur. The LED is pulse- stretched for viewing effect.

Link OK (LNK) When lit, this green LED indicates that a link exists between the FOT-DF24 and the device at the other end of the ﬁber optic segment. LNK remains lit as long as the link is maintained. To maintain the link, the transceiver generates a 1 MHz idle signal when it is not transmitting data. Both ports can show a valid link.

Active Port (ACT) This yellow LED indicates which ﬁber optic port is handling all network trafﬁc through the transceiver. Only one port can be active; the inactive port ACT LED is off. A ﬂashing ACT LED indicates that the port is in the idle state. A slow ﬂash indicates that the time-out period is set to 10 seconds; a fast ﬂash indicates that the time-out period is set to 2 seconds.

If you have questions, or need additional help, contact Cabletron Systems Technical Support as follows:

By phone:	Monday through Friday,
	8 am to 8 pm EST at
	(603) 332-9400
By CompuServe:	GO CTRON from any ! prompt
By Internet mail:	support@ctron.com

LANVIEW is a registered trademark of Cabletron Systems, Inc.

FOT-DF24is a trademark of Cabletron Systems, Inc.

CompuServe is a registered trademark of

CompuServe, Inc.

Ethernet is a trademark of Xerox Corp.

FCC NOTICE

This device complies with Part 15 of the FCC rules. Operation is subject to the following two conditions: (1) this device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.

NOTE: This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment uses, generates, and can radiate radio frequency energy and if not installed in accordance with the operator’s manual, may cause har mful interference to radio communications. Operation of this equipment in a residential area is likely to cause interference in which case the user will be required to correct the interference at his own expense.

WARNING: Changes or modiﬁcations made to this device which are not expressly approved by the party responsible for compliance could void the user’s authority to operate the equipment.

DOC NOTICE

This digital apparatus does not exceed the Class A limits for radio noise emissions from digital apparatus set out in the Radio Interference Regulations of the Canadian Department of Communications.

NOTICE

Cabletron Systems reserves the right to make changes in speciﬁcations and other information contained in this document without prior notice. The reader should in all cases consult Cabletron Systems to determine whether any such changes have been made. The hardware, ﬁrmware, or software described in this manual is subject to change without notice.

IN NO EVENT SHALL CABLETRON SYSTEMS BE LIABLE FOR ANY INCIDENTAL, INDIRECT, SPECIAL, OR C O N S E QU E N T I A L DA M AG E S W H AT S O E V E R (INCLUDING, BUT NOT LIMITED TO, LOST PROFITS) ARISING OUT OF OR RELATED TO THIS MANUAL OR THE INFORMATION CONTAINED IN IT, EVEN IF CABLETRON SYSTEMS HAS BEEN ADVISED OF, KNOWN OR SHOULD HAVE KNOWN, THE POSSIBILITY OF SUCH DAMAGES.

Printed in the United States of America

Part number: 9030729-02 August 1994

FOT-DF24

802.310BASE-FL/FOIRL Redundant Transceiver

The FOT-DF24™ ﬁber optic transceiver is designed to link two Ethernet™ devices through ﬁber optic cable. Dual ﬁber optic ports with ST type connectors provide redundant data paths for critical applications.

Primary Port

FOT-DF24	SQE
FOT-DF24	P	S	X	R	C
802.3 10BASE-FL/FOIRL	W	Q	M	V	L
REDUNDANT TRANSCEIVER	R	E	T C		N
WITH LANVIEW®	1 LNK				TX
	ACT				RX
	SN
	LNK				TX
	2 ACT				RX

MIN MAX

Back-up Port

If the primary port (port 1) receives no data for either 2 or 10 seconds (switch selectable), the port enters the idle state. During the idle state, if the back-up port (port 2) receives data it becomes the active port. When the primary port senses data again, it switches back to become the active port. The two transceiver ports can be connected to the same network device, different network devices or even different networks.

REQUIREMENTS

The FOT-DF24 Transceiver complies with IEEE 802.3 10BASE-FL/FOIRL speciﬁcations. Use the FOT-DF24 with Version 1, Version 2, and/or IEEE 802 . 3 equipment. For best network performance, observe the following network guidelines.

Fiber Optic Requirements

The FOT-DF24 supports 50/125 ∝m, 62.5/125 ∝m, and 100/140 ∝m ﬁber optic cable. Link length depends on cable type and system ﬁber optic budget. The FOT- DF24 supports a maximum link length of 2 km.