Cisco Ethernet switch Manuel d'utilisateur Page 18

  • Télécharger
  • Ajouter à mon manuel
  • Imprimer
  • Page
    / 84
  • Table des matières
  • MARQUE LIVRES
  • Noté. / 5. Basé sur avis des utilisateurs
Vue de la page 17
181818
© 2002, Cisco Systems, Inc. All rights reserved.
l2-security-bh.ppt
CAM Table Full!
¥ Dsniff (macof) can generate 155,000 MAC entries on a
switch per minute
¥ Assuming a perfect hash function, the CAM table will be
completely filled after 131,052 (approx. 16,000 x 8) entries
Since hash isnÕt perfect it actually takes 70 seconds to fill the
CAM table
¥ Once table is full, traffic without a CAM entry floods on the
local VLAN, but NOT existing traffic with an existing CAM
entry
¥ This attack will also fill CAM tables of adjacent switches
CAT6506 (enable) sho cam count dynamic
Total Matching CAM Entries = 131052
10.1.1.22 -> (broadcast) ARP C Who is 10.1.1.1, 10.1.1.1 ?
10.1.1.22 -> (broadcast) ARP C Who is 10.1.1.19, 10.1.1.19 ?
10.1.1.26 -> 10.1.1.25 ICMP Echo request (ID: 256 Sequence number: 7424) ßß
ßß
OOPS
10.1.1.25 -> 10.1.1.26 ICMP Echo reply (ID: 256 Sequence number: 7424) ßß
ßß
OOPS
Snoop output on non-SPAN port 10.1.1.50
Snoop output on non-SPAN port 10.1.1.50
Vue de la page 17
1 2 ... 13 14 15 16 17 18 19 20 21 22 23 ... 83 84

Commentaires sur ces manuels

Pas de commentaire