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Conference 7.286::fddi

Title:	FDDI - The Next Generation

Moderator:	NETCAD::STEFANI

Created:	Thu Apr 27 1989
Last Modified:	Thu Jun 05 1997
Last Successful Update:	Fri Jun 06 1997
Number of topics:	2259
Total number of notes:	8590

690.0. "several questions on DC and DB ???" by MARS02::THOMAS () Wed Sep 02 1992 13:42

	My customer asked me some technical questions about the DECconcentrator
500 and the DECbridge 620:

	* which processors are there in the DC (68000 for general purpose + ?)
and in the DB (68020 for general purpose + ?) ?
	* which bus is there in the DC and in the DB ?
	* MTBF of the DC and the DB ?
	* time to be ready (after a power on) for the DC and the DB ?
	* how many adresses are supported on the DB ?
	* are all the protocols (DECNET, IP, OSI, IPX, SPX, ATK ...) translated
by the DB ?
	* are the configuration of the DC and DB (IP, trap ...) and the adress
and protocol filterings for the DB kept in the DB (without need to load any
thing at power on) ?
	* is there any limitation to configure and manage DC and DB only with
SNMP from an HP OPENVIEW station ?
	* is trap mechanism only available with SNMP protocol (no "trap"
with RBMS or Out Of Band Management)?
	* what info do we have with leds on the DC and the DB (sorry, i have no
documentation here)?

	That 's a lot.

	THANK YOU for all the answers


	Bernard THOMAS

T.R	Title	User	Personal Name	Date	Lines
690.1	one more question	MARS02::THOMAS		`Fri Sep 04 1992 07:52`	14
	Is this optical fiber supported by the DECNIS : 62.5/125 micron multimode optical fiber numeric aperture 0.275 bandwith 300 MHz/Km at 1,300 nm !!!!! attenuation 1.5 db/Km at 1,300 nm Regards I need answers to this question and the questions of 690.0 before tuesday (if possible). Thanks.
690.2	previous question for DC and DB	MARS02::THOMAS		`Fri Sep 04 1992 07:56`	6
	The previous question was about the DC 500 and the DB 600 (not the DECNIS). I already asked the question for the DECNIS in the DECNIS note file. Bernard
690.3	Apply the DECNIS question to Modular PMD's	BONNET::LISSDANIELS		`Fri Sep 04 1992 08:37`	9
	the fiber supported should not differ between DC500/DB600 and DECNIS. the modular PMD's that the DECNIS will use follows FDDI standard as all our other FDDI products do. The generic question is: Is the Fiber in .-2 good enough for Multimode FDDI ? Torbjorn
690.4	Should work up to 1.6 Km	LEVERS::KIRK	tis a gift to be simple	`Fri Sep 04 1992 10:09`	38
	< Is this optical fiber supported by the DECNIS : < < 62.5/125 micron multimode optical fiber < numeric aperture 0.275 < bandwith 300 MHz/Km at 1,300 nm !!!!! < attenuation 1.5 db/Km at 1,300 nm < The problem with this fiber is, as you realize, the 300 MHz-Km bandwidth. This is significantly different from the 500 MHz-Km value required for our FDDI systems. The effect of using a lower bandwidth optical fiber will be to reduce the length of fiber over which an acceptable Bit Error Rate can be maintained. Therefore we can not support use of this optical fiber for a full 2.0 kilometer link. Chris Baldwin wrote a memo detailing supportable distances for fibers that do not meet the PMD requirements. It deals with alternate fiber sizes primarily, but also discusses the lower bandwidth fiber. The relevant paragraph is reproduced here. 4. Up to 1.6 km lengths of 50,62.5,85/125 or 100/140 fiber that was not characterized for chromatic dispersion can be supported provided that the installed cableplant has a modal bandwidth of 200 MHz at 1300 nm over its full length. The fiber in question should meet this criteria. That's the official stance. Dick Kirk FDDI Engineering NAC LEVERS::KIRK
690.5		LEVERS::ANIL		`Fri Sep 04 1992 11:42`	55
	I'm not sure if it's a good idea to give out details of the internal architecture such as processors used etc, since they have no way of knowing how we use them. Anyway here are some answers: > * which processors are there in the DC (68000 for general purpose + ?) >and in the DB (68020 for general purpose + ?) ? DC - 68000. DB - multiple 68020's working in parallel, and a bit-slice processor to handle full-speed FDDI. > * MTBF of the DC and the DB ? For the DB - around 25000 hours. Not sure on the DC. > * time to be ready (after a power on) for the DC and the DB ? Around a minute > * how many adresses are supported on the DB ? ~14K > * are all the protocols (DECNET, IP, OSI, IPX, SPX, ATK ...) translated >by the DB ? Yes > * are the configuration of the DC and DB (IP, trap ...) and the adress >and protocol filterings for the DB kept in the DB (without need to load any >thing at power on) ? Yes. If the IP address is administrated via Bootp, the device will get its address from a server every time it comes up. (but its kept in non-volatile RAM if configured through ELMS) > * is there any limitation to configure and manage DC and DB only with >SNMP from an HP OPENVIEW station ? Can be managed by any NMS that complies to SNMP > * is trap mechanism only available with SNMP protocol (no "trap" >with RBMS or Out Of Band Management)? The ELMS poller provides functionality that simulates alarms by polling critical variables at regular intervals. There's no asynchronous notification from OBM. > * what info do we have with leds on the DC and the DB (sorry, i have no >documentation here)? From memory, there's a good/bad LED per FRU, a working/not-working LED per FDDI port, a forwarding/broken LED for every bridge port. There may be others I've missed. Anil