Conference netcad::hub_mgnt

3578.0. "Repeater MIB questions" by NCMAIL::SCHEID () Mon Jun 03 1996 08:38

    
    Given the following MIB definitions from the DEC extended repeater MIB-
    
    erptrAddrDBPortGroupIndex OBJECT-TYPE
    	SYNTAX INTEGER (1..1024)
    	ACCESS read-only
    	STATUS mandatory
    	DESCRIPTION 
    		"This object indentifies the group containing the port on
    		which this entry's MAC address was seen"
    	::={ erptrAddrDBPortAddrEntry 3}
    

    erptrAddrDBPortIndex OBJECT-TYPE
    	SYNTAX INTEGER (1..1024)
    	ACCESS read-only
    	STATUS mandatory
    	DESCRIPTION 
    		"This object indentifies the group containing the port on
    		which this entry's MAC address was seen"
    	::={ erptrAddrDBPortAddrEntry 3}
    
    
    and given the following MIB values for these variables - 
    
    DECrepeater 90TS -> erptrAddrDBPortGroupIndex = 1; erptrAddrDBPortIndex
    = 1-9
    
    DECrepeater 900TM -> erptrAddrDBPortGroupIndex = 1; erptrAddrDBPortIndex
    = 1-33
    Portswitch 900TP -> erptrAddrDBPortGroupIndex = 1-33; erptrAddrDBPortIndex
    = 1
    
    
    why does the Portswitch  appear to do things opposite of the other
    repeaters. 
    
    
    
    
    

    Section 1.1.2 in the DEC extended repeater MIB states the following: 
    
    --     A DEChub 900 repeater module divides its ports into one or more
    --     groups. In this context, a group is an indivisible collection of
    --     ports which functions either as a single independent repeater unit or
    --     as part of a larger distributed repeater unit.
    -- 

    This means that in Digital's implementation of RFC 1516 and DEC's
    repeater MIB extentions, a port-group is defined as that collection of
    ports which must always lan hop together.  The DECrepeater 90TS and
    DECrepeater 900TM are not per-port switchable repeaters. All ports in
    each of these devices must lan-hop together.  Therefore they have only
    one group of 9 or 33 ports.
    
    The Portswitch 900TP, of course, is a per port switchable repeater.
    Each port can lan hop independantly. Hence it consists of 33 groups of
    1 port.
    
    For further illustration, the Portswitch 900FP has something like 6 groups,
    each containing 2 ports. In this repeater, pairs of ports must always
    lan hop together.