Cabletron Systems EMM-E6 User Manual

Page of 118
Security
7-12
Enabling Security and Traps
transmitted clean to all ports on that channel unless security has been enabled 
there, too. Packets bridged to Channel A will always be transmitted clean to all 
ports, regardless of lock status; however, careful bridge configuration and 
prudent use of each port’s forwarding and blocking abilities can provide some 
measure of security in this case.
Security must be disabled on any port which is connected to an external bridge, 
or the bridge will discard all packets it receives as error packets (since the CRC 
is not recalculated after a packet is scrambled). 
Security should also be disabled on any port which is supporting a trunk 
connection, unless you are sure that no more than 34 source addresses will 
attempt to use the port, and you have secured all necessary addresses. Note 
that, with the newest versions of security, a 
LANVIEW
SECURE
 port that sees 
more than 35 addresses in its Source Address table (or exactly 35 addresses for 
two consecutive aging intervals) is considered unsecurable and cannot be 
locked.
Full security should not be implemented on any port which supports a name 
server or a bootp server, as those devices would not receive the broadcast and 
multicast messages they are designed to respond to (partial security — which 
does not scramble broadcasts or multicasts — will not affect their operation). 
Note that users who require responses to broadcast or multicast requests can 
still operate successfully if their ports are fully secured, as the reply to a 
broadcast has a single, specific destination address.
In general, scrambling is most effective when employed in a single chassis which 
contains only 
LANVIEW
SECURE
 MIMs operating on channels B and/or C; 
remember, non-
LANVIEW
SECURE
 MIMs and any ports operating on Channel A do 
not support scrambling as part of their security functionality.
Enabling Security and Traps
You can enable or disable all applicable protections by locking or unlocking ports 
via the repeater, module, or port Security window, as described in the sections 
below. There are two levels of lock status to choose from: if you select Full lock 
status, the port will stop learning new source addresses, accept packets only from 
secured source addresses, employ either full or partial eavesdrop protection (as 
configured), and take the configured steps (send trap and/or disable port) if a 
violation occurs; if you select Continuous lock status, the port will implement the 
configured level of eavesdrop protection, but continue to learn source addresses 
and allow all packets to pass, effectively disabling intruder protection.
Enabling and disabling traps from the Security windows has the same effect as 
enabling and disabling them from the Source Address windows; you can enable 
and disable the following traps: