to get the file

WAF – positive filtering model
• allows only “known good” traffic to pass
– Some allow, all deny
– a WAF running a positive security approach
is like a paranoid security guard who
automatically assumes that everyone he
doesn‟t recognize is malicious.
– With this model, WAF catches the unknown
(or zero-day) attacks
– it does not need to regularly have its
signature file updated.
– It requires extensive training or learning
time, which takes much up-front time and
energy
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