Lancom Systems LCOS 3.50 - Manual (Page 117)

̈ Chapter 8: Firewall LANCOM Reference Manual LCOS 3.50
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The LANCOM Firewall uses several lists for checking data packets, which are
automatically generated from Firewall rules, resulting Firewall actions or by
active data connections:
̈ Host block list
̈ Port block list
̈ Connection list
̈ Filter list
When a data packet should be routed via the IP router, the Firewall uses the
lists as follows:
ቢ The first check is, whether the packet was coming from a workstation
belonging to the host block list. If the sender is blocked, the packet will
be discarded.
ባ If the sender is not blocked in this list, the port block list will be checked,
if the used port/protocol combination on the destination PC is closed. In
this case the packet will be discarded.
ቤ If sender and destination are not blocked in the first two lists, then it will
be checked whether a connection entry exists for this packet in the con-
nection list. If such an entry exists, then the packet will be handled as
noted in this list.
ብ If no entry has been found for the packet, then the filter list will be
searched, whether a suitable entry exists and the action indicated in this