While the review of Check Point FireWall-1 ("Firewall Software for NT and Unix," June Software Lab Report) was favorable overall, it was inaccurate regarding Check Point's Stateful Inspection technology. Stateful Inspection implements state tables, which maintain extensive state-related information regarding active and subsequent communications attempts and are used to make intelligent security policy-related decisions to allow or disallow communications through the firewall.
The article asserted incorrectly that if the state tables become corrupt, the network could be exposed. The state tables are kept in the OS kernel memory and cannot become corrupted like disk files. If the system fails due to a hardware or software error, new tables are allocated and no old (corrupted) data is valid. Furthermore, the data in the state tables represents active connections
, so if a hardware or software error were to occur, the connections would no longer be active and therefore disabled, preserving the security of the network. Readers can obtain more information at
http://www.checkpoint.com/products/firewall/stateful/index.html
or by sending e-mail to info@checkpoint.com.
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On State Tables
