Hello all,

This task requires that FTP/web traffic be allowed to go out from the
network. The access-list that configures it in P.G is as follows

ip access-list extended IE4ME
 permit tcp 150.100.40.0 0.0.0.255 any eq www
 permit tcp 150.100.40.0 0.0.0.255 any eq ftp
 permit tcp 150.100.40.0 0.0.0.255 any eq ftp-data
 remark Those three lines cover stuff the users generate
 permit tcp 150.100.40.0 0.0.0.255 any established
 remark That line is necessary for the WWW/FTP server's responses
since ports vary
 permit ospf any any

I think the user part of the access-list assumes that users will be
using active FTP and will have connection to port 20 & 21 on the
server.
So the second and third line of the list are good
However, for the server part it assumes standard FTP , in which user
initiates connection to randomly selected  port on the server and to
allow the reply the server part of the list allows all ports as reply
to the user using established Keyword.

 I think this problem can only be solved if we consider either one of
the two FTP modes or both the FTP modes. Considering both the FTP
modes requires us to allow all the ports in both the directions

If we consider active FTP in that the server part will look something
like this and will be much simpler.

permit tcp 150.100.40.0 0.0.0.255 eq ftp-data  any
permit tcp 150.100.40.0 0.0.0.255 eq www any

I would like to understand the reason for using different modes for
user and servers
 because it seems like user part is based on active FTP and server
part is based on passive FTP.

Thanks
Suresh

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