3Com VCX V7122, User Manual, Page: 355 / 488

V7122 Gateway User Guide
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ƒ Rule #22: traffic from the subnet 10.4.xxx.yyy destined to ports 4000 to 9000 is always
blocked, regardless of protocol.
ƒ All other traffic is allowed.
More complex rules may be defined, relying on the ‘single-match’ process described above.
Figure 117 shows an advanced example of an access list definition using ini file:
Figure 117
Advanced Example of an Access List Definition using ini File
[ ACCESSLIST ]
FORMAT AccessList_Index = AccessList_Source_IP, AccessList_Net_Mask,
AccessList_Start_Port, AccessList_End_Port, AccessList_Protocol,
AccessList_Packet_Size, AccessList_Byte_Rate, AccessList_Byte_Burst,
AccessList_Allow_Type;
AccessList 10 = 10.0.0.0, 255.0.0.0, 0, 65535, any, 0, 40000, 50000, allow ;
AccessList 15 = 10.31.4.0, 255.255.255.0, 4000, 9000, any, 0, 0, 0, allow ;
AccessList 20 = 0.0.0.0, 0.0.0.0, 0, 65535, any, 0, 0, 0, block;
[ \ACCESSLIST ]
Explanation of the example access list:
This access list consists of three rules:
ƒ
Rule #10: traffic from the subnet 10.xxx.yyy.zzz is allowed if the traffic rate does not
exceed 40 KB/s.
ƒ Rule #15: if a packet didn't match rule #10, that is, the excess traffic is over 40 KB/s, and
coming from the subnet 10.31.4.xxx to ports 4000 to 9000, then it is allowed.
ƒ Rule #20: all other traffic (which didn't match the previous rules), is blocked.
The internal firewall can also be configured using the Embedded Web Server (see
Configuring the Firewall Settings ).
Network Port Usage
The following table lists the default TCP/UDP network port numbers used by the gateway.
Where relevant, the table lists the
ini file parameters that control the port usage and provide
source IP address filtering capabilities.
Table 72
Default TCP/UDP Network Port Numbers
Port Number Peer Port Application Notes
2 2 Debugging interface Always ignored
23 - Telnet
Disabled by default (TelnetServerEnable).
Configurable (TelnetServerPort), access
controlled by WebAccessList