Live Traffic Analysis of TCP/IP Gateways

We enumerate a variety of ways to extend both stat i st i cal and si gnature-based i ntrusi on-detect i on anal ysi s techni ques to moni tor network tra c. Speci cal l y, we present techni ques to anal yze TCP/IP packet streams that ow through network gateways f or si gns of mal i ci ous act i vi ty, nonmal i ci ous f ai l ures, and other except i onal events. The i ntent i s to demonstrate, by exampl e, the ut i l i ty of i ntroduci ng gateway survei l l ance mechani sms to moni tor network tra c. We present thi s di scussi on of gateway survei l l ance mechani sms as compl ementary to the l teri ng mechani sms of a l arge enterpri se network, and i l l ustrate the usef ul ness of survei l l ance i n di rect l y enhanci ng the securi ty and stabi l i ty of network