Access list question [7:36124]

2002-02-21 Thread Justin M. Clark
can someone explain to me exactly what this line means: access-list 101 permit tcp any any established thanks Justin Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=36124&t=36124 -- FAQ, list archives, and subscription info: ht

Re: Access list question [7:36124]

2002-02-21 Thread Regis Thornton
""Justin M. Clark"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > can someone explain to me exactly what this line means: > > access-list 101 permit tcp any any established > > thanks > Justin Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=36125&t=36124 ---

Re: Access list question [7:36124]

2002-02-21 Thread Brian
If you're on your lan and go to an external website, you presumably want the data to be able to get back to you, you dont want to write a permit statement for the return traffic of every site people visit. This allows tcp traffic from any ip to any ip in the direction implied in the config.

RE: Access list question [7:36124]

2002-02-21 Thread David Jones
Justin, This is typically used in an Internet/NAT situation where you are allowing something from the Internet to come back in, only if it's a reply to a request that originated from inside your network. For instance, with a router connected to the Internet, you typically want an access-list app

Re: Access list question [7:36124]

2002-02-21 Thread Brian
Or for a better explanation, see the ack bit discussion on http://www.daemon.org/tcp.html. Brian On Thu, 21 Feb 2002, Justin M. Clark wrote: > can someone explain to me exactly what this line means: > > access-list 101 permit tcp any any established > > thanks > Justin Message Poste

Re: Access list question [7:36124]

2002-02-21 Thread Steven A. Ridder
I can get through it by just setting the ack bit in the IP packet on. That's all it check for. Not very secure. ""Justin M. Clark"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > can someone explain to me exactly what this line means: > > access-list 101 permit tcp any any estab

Re: Access list question [7:36124]

2002-02-21 Thread MADMAN
packets coming into the router that are part of a session initiated from within. I'm sure someone came be more eloquent in describing it though:) Dave "Justin M. Clark" wrote: > > can someone explain to me exactly what this line means: > > access-list 101 permit tcp any any established > >

Re: Access list question [7:36124]

2002-02-21 Thread Brian
Which is why most people who are concerned use firewalls that actually keep a table of open connections. Brian On Thu, 21 Feb 2002, Steven A. Ridder wrote: > I can get through it by just setting the ack bit in the IP packet on. > That's all it check for. Not very secure. > ""Justin M.

RE: Access list question [7:36124]

2002-02-21 Thread Priscilla Oppenheimer
That's a good conceptual explanation. I would add that technically, it allows TCP packets that have the ACK bit set. In other words, it allows packets that are acknowledging another packet. That means it would not allow an incoming SYN used to set up a session, but it would allow a reply to a

Re: Access list question [7:36124]

2002-02-21 Thread Priscilla Oppenheimer
IP doesn't have an ACK bit. You mean TCP. Picky, picky, I know. ;-) Priscilla At 07:00 PM 2/21/02, Steven A. Ridder wrote: >I can get through it by just setting the ack bit in the IP packet on. >That's all it check for. Not very secure. >""Justin M. Clark"" wrote in message >[EMAIL PROTECTED]

RE: Access list question [7:36124]

2002-02-22 Thread Evans, TJ
PROTECTED] Subject: RE: Access list question [7:36124] That's a good conceptual explanation. I would add that technically, it allows TCP packets that have the ACK bit set. In other words, it allows packets that are acknowledging another packet. That means it would not allow an incoming SYN u