It's too bad FTP didn't last for a "markedly brief time." What a silly protocol! ;-)
Priscilla At 04:24 PM 10/30/01, Lange, Eric wrote: >e7phem7er7al (i-fem'?r-?l) >adj. >Lasting for a markedly brief time: "There remain some truths too ephemeral >to be captured in the cold pages of a court transcript" (Irving R. Kaufman). >Living or lasting only for a day, as certain plants or insects do. >n. >A markedly short-lived thing. > >I needed to look it up.... : ) >-Eric > > >-----Original Message----- >From: Priscilla Oppenheimer [mailto:[EMAIL PROTECTED]] >Sent: Tuesday, October 30, 2001 2:43 PM >To: [EMAIL PROTECTED] >Subject: Re: FTP Server [7:24525] > > >If it's not passive mode, the data channel is initiated by the server from >port 20 (FTP data) to the ephemeral port provided by the client in its PORT >command. Ephemeral just means a short-lived port with a number greater than >1023. > >If it is passive mode, then the data channel is initiated by the client >from an ephemeral port to an ephemeral port provided by the server in its >PASV command. > >In other words, access lists with FTP are tricky. > >Priscilla > >At 03:14 PM 10/30/01, Jonathan Hays wrote: > >Michael Williams wrote: > > > > > That would work, although you don't need the "deny ip any any" as there >is > > > always an implied "deny all" at the end of the access list. > > > > > > However, to protect yourself from unwanted traffic/attacks, you can >changed > > > your access list to only allow traffic incoming on port 21 (eq ftp): > > > > > > access-list 110 permit tcp any host 192.3.10.10 eq ftp > > > > > > >Don't we also want a ACL line for the ftp data channel? > > > >access-list 110 permit tcp any host 192.3.10.10 eq ftp-data > > > >And if the server is using passive ftp > > > >access-list 110 permit tcp any host 192.3.10.10 gt 1023 established >________________________ > >Priscilla Oppenheimer >http://www.priscilla.com ________________________ Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=24713&t=24525 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
