User Manual Part 1

Table Of Contents
The Safe@Office Firewall
Chapter 2: Safe@Office Security 41
Table 13: Establishment of Passive FTP Connection
Step Channel
Type
Description Source TCP
Source
Port
Destination TCP
Destination
Port
1 CMD Client initiates a
PASV command to
the FTP server on
port 21
FTP
client
C >
1023
FTP server 21
2 CMD Server responds
with data port
information P >
1023
FTP
server
21 FTP client C
3 Data Client initiates data
connection to
server on port P
FTP
client
D >
1023
FTP server P
4 Data Server
acknowledges
data connection
FTP
server
P FTP client D