Trend Micro InterScan Gateway Security Appliance M-Series ...

Trend Micro InterScan Gateway Security Appliance M-Series Administrator’s Guide
2-10
The appliance supports two transparent proxy modes (“operation modes”):
• Transparent proxy mode
• Fully transparent proxy mode
The major difference between transparent and fully transparent proxy modes is the
“actual transparency” of the appliance with the destination server. The appliance
creates an independent connection to the destination server. In transparent proxy
mode, the destination server is aware of the IP address of the appliance.
In neither mode can the appliance keep the client’s MAC address when delivering the
request to the server.
Transparent Proxy Mode
InterScan Gateway Security Appliance enforces transparency through the following
behavior:
• Clients do not see the presence of additional filters/scanners unless a violation is
detected.
• Administrators do not need any additional configuration on the client side.
• The destination servers still see the appliance IP address as the requestor.
For an illustration of how the appliance processes HTTP, FTP, SMTP, or POP3 traffic
in transparent proxy mode, see the figure below.
Source IP:
10.2.2.23
Server Internet
Source IP:
10.2.2.23
Router
(Default gateway
of InterScan
appliance)
EXT
port
proxy handlers
10.2.2.23
Operation mode:
Transparent proxy
INT
port
10.2.211.136
FIGURE 2-7. In transparent proxy mode, the client's IP address becomes
that of the appliance
Source IP:
10.2.211.136
Switch
Client