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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

202.0. "Some simple customer questions/concerns" by ODIXIE::LACORTI () Mon Feb 11 1991 18:25

    I dont know much about FDDI so please bear with me....
    
    	One of our customers is looking into FDDI for the future and needs
    to put a plan together right now as a new building is coming and they
    want to have the cable installed as part of the construction.  The
    customer has several concerns/questions..
    
    1. The dual rings will be in the new building.  THe customer then wants
    to go from concentrator to concentrator between the buildings so that
    the old building will have a concentrator in it.  He is afraid that
    someone might accidentally cut the cable, so he want to run 2 sets of
    fiber cables from concentrator to concentrator with failover if
    something happens to the first cable.  Is this possible or legal?
    I understand about dual homing and will present that if it is not
    possible.
    
    2. I dont think this one is true, but I want to verify.  The customer
    wants to know if the concentrator will act like a bridge.  i.e. will
    it filter the packets.  His concern is that he will be running intense
    imaging in the future and doesnt want the FDDI network to ever get
    bogged down.  I dont think that 100mb/sec will, but he has these
    problems over ethernet now (has no bridges yet, but will) 
    and is concerned.  I have a feeling that he will have to wait for an
    FDDI-FDDI bridge.
    
    3.  Will DECelms support non-Digital bridges.  The customer cannot
    guarantee  that any bridges that are purchased will be Digital's
    since they are govt and procurement is done by RFP. What bridges will/
    does DECelms support? 
    
    	Sorry if some of these questions seem naive, but I am not a
    networking specialist, the customer needs the answers now, and our
    networking specialists are all at network U.
    
    				Thanks
    
    				Sandy
T.RTitleUserPersonal
Name		DateLines
202.1KONING::KONINGLietuva laisva!Mon Feb 11 1991 18:4518
(1) yes, you should run multiple fibers between buildings, and use dual
homing.  If you're really paranoid, run them in separate trenches so a
backhoe doesn't cut them both at once.  Get the FDDI system level overview
and the fiber decconnect books for more information.  (In the latter you
should also find recommendations for fiber counts between buildings: those
tend to be for a lot more than just one or two pairs.  The reasoning:
pulling one cable is expensive: using a 12-pair cable rather than a 1-pair
cable makes no real difference in installation cost, but gives you a lot
of expandability.)

(2) Concentrators are not bridges.  Think of them as similar to DEMPRs.
Note however that no FDDI station can lock out the others; if one has enough
traffic to saturate the FDDI, then it will do so if no one else wants to
send.  But when other nodes have traffic, they will take away from the
hog.  There is some delay in doing this: if you have one hog, then the
other stations have about 8 ms delay.  Still not a bad deal.

	paul
202.2DECelms -> SNMPJUMP4::JOYGet a life!Tue Feb 12 1991 16:3412
    (3)  Currently, DECelms will only support Digital bridges (including
    LANbridges), ChipCom's broadband bridge which we resell and the
    Metrowave bridge. In the future, DECelms will support SNMP for TCP/IP
    networks. If another vendor's bridge can be managed by SNMP and
    supports the MIB1 and MIB2 extensions, then we will be able to manage
    those as well. There is a series of steps that DECelms will go thru to
    attain SNMP support as it moves towards being incorporated into DECmcc.
    THe SNMP support has not been announced yet except as a program
    announcement so the customer should be told this under PID.
    
    Debbie
202.3DECelms will not support SNMPLEVERS::CIARFELLASaabless and happyWed Feb 13 1991 20:0228
    re: .-1
    
    Just to clarify ... 
    
    DECelms is not going to support SNMP, but SNMP agents are being added
    to FDDI product firmware.  DECelms is RMBS-protocol based, whereas SNMP
    is based upon the UDP/IP Internet protocols.  Also, the information
    managed by each and how it is managed can be quite different.

    In the future, DECelms functionality will be incorporated into DECmcc.  
    After a while DECelms will eventually disappear and DECmcc will be the
    primary management station.  

    At this time SNMP-based agents are being added to the FDDI hardware 
    products (bridges, concentrator), but you will need an SNMP management 
    station which supports MIB II, the proposed FDDI MIB, the proposed Bridge 
    MIB, and DEC's new vendor extensions for FDDI.

    Digital's Management Station for Ultrix (MSU) currently supports SNMP 
    management and will also support RBMS management of Digital's FDDI 
    products soon. 

    DECmcc is also going to support SNMP management of FDDI networks in the 
    near future, in addition to the SNMP management it currently provides.
    
    Paul C