Re: FTP and WPA problem

Jeff Liebermann wrote:
"Peter Crosland" <g6jns@xxxxxxxxxxx> hath wroth:

My Acer Aspire 3003 laptop works fine when connected using the
inbuilt Ethernet port for all applications including FTP uploads
using SmartFTP or a an FTP program built into some application
software I have. When I fit a Netgear WG511T Cardbus card this works
fine for browsing and email. However, if I try to use an FTP program
such as Smart instead of the Ethernet card neither of the FTP
programs will work. I am using WPA with a 128bit preshared key.
This is true if I use the standard Windows drivers for the card or
the ones supplied by Netgear. I am running a fully patched Windows
XP Home and the machine has 1GB of memory. AFAICS there must be some
incompatibility be the FTP protocol and WPA but I cannot see why
that should be. I would expect the WPA protocol to be transparent.
Any constructive suggestions would be welcome as my Googling has not
turned anything up.

Peter Crosland

What maker and model router are you using? Extra credit for the
firmware version.

Weird. Try using the PASV mode for ftp. It should be a setting
(somewhere) in SmartFTP[1]. I don't think it will really do anything
but it's worth a try.

It would also be interesting if you tried ftp with encryption
disabled.

In theory, encryption should not have anything to do with ftp
functionality. However, ftp is unique in that the router has to do
something odd with ftp in order to impliment NAT. In order to
seperate mutliple ftp streams, the router has to sniff the payload in
order to extract the port numbers used. Ordinarily, the port numbers
are in the header, but not for ftp. It's possible that your
unspecified model wireless router is having a problem doing that.
Perhaps a firmware update might help.

Thanks for that Jeff. I have tried passive mode and it makes not difference.
I am using a Draytek 2800G with the latest UK firmware that has been around
for ages and AFAIK is quite stable. I should also have said that the problem
is also there if I use the WEP protocol. I have not tried with an open
network but will do so but this will not be a solution that I can use for
security reasons. One other clue is that I have now tried my Dell Inspiron
6400 fitted with a Gigabyte internal wireless card and works perfectly when
running the same software. To me this would suggest that the incompatibility
is with the WG511T in some way. Signal sterngth is not a problem as both
cards connect happily at 108Mbps.

Peter Crosland



.

Relevant Pages

  • RE: Telnet/ftp problems SBS2000
    ... Please make sure your client computers are configured as both Firewall ... will find two options "Enable folder view for FTP sites" and "Use Passive ... that the control connection has been successfully established, ... (other than port 21) ...
    (microsoft.public.windows.server.sbs)
  • SMART FTP
    ... Ftp Client To Smart How ... Active Mode Ftp Port Limit Smart ... Pro Keygen Ftp Smart Client ...
    (sci.anthropology)
  • FTP transfer port
    ... FTP transfer port ... the FTP server "listens" for client connections on its port 21. ... it will establish a separate control connection and data connection with ...
    (bit.listserv.ibm-main)
  • Re: Hacked? External address knocks on internal private address...
    ... The important part of your message is that FTP is allowed out... ... You open a connection to an FTP Server and logon. ... When you ask the server for a file the server issues a "PORT" command ... so it can open a port on the firewall to allow the incoming Data ...
    (comp.security.firewalls)
  • Re: Question: FTP via alternate port
    ... The problem with FTP is that it requires two ports to operate. ... FTP command stream in order to dynamically open that port for the data ... Ideally the attacker would want to upload another tool onto the ...
    (Pen-Test)