3.4.3. ARP Cache .................................................................................68
3.5. The IP Rule Set ......................................................................................73
3.6. Schedules .............................................................................................77
3.7.1. Overview ...................................................................................79
3.8.2. Time Servers ..............................................................................83
3.9. DNS Lookup .........................................................................................87
4. Routing ...........................................................................................................89
4.1. Overview ..............................................................................................89
4.2. Static Routing ........................................................................................90
4.2.4. Proxy ARP .................................................................................96
4.3.1. Overview ...................................................................................98
4.4. Dynamic Routing ................................................................................. 103
4.4.2. OSPF ...................................................................................... 104
4.5.1. Overview ................................................................................. 110
4.6. Transparent Mode ................................................................................ 119
5. DHCP Services .............................................................................................. 127
5.1. Overview ............................................................................................ 127
5.2. DHCP Servers ..................................................................................... 128
5.4. DHCP Relaying ................................................................................... 131
5.5. IP Pools .............................................................................................. 132
6. Security Mechanisms ....................................................................................... 135
6.1. Access Rules ....................................................................................... 135
6.1.1. Introduction .............................................................................. 135
6.1.2. IP spoofing ............................................................................... 135
6.2.1. Overview ................................................................................. 138
6.2.2. HTTP ...................................................................................... 139
6.2.3. FTP ......................................................................................... 140
6.2.4. TFTP ....................................................................................... 145
6.2.5. SMTP ...................................................................................... 146
6.2.6. POP3 ....................................................................................... 151
6.2.7. SIP .......................................................................................... 152
5
User Manual