Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

What is the difference between wrting the port no. after source and after destination in ACL

What is the difference between wrting the port no. after source and after destination in ACL

ex : permit tcp host 10.1.1.1 eq 1389 10.2.2..0 0.0.255.255

And 

permit tcp 10.2.2..0 0.0.255.255 host 10.1.1.1 eq 1389

1 ACCEPTED SOLUTION

Accepted Solutions
Cisco Employee

 permit tcp host 10.1.1.1 eq

 

permit tcp host 10.1.1.1 eq 1389 10.2.2..0 0.0.255.255

Will permit TCP traffic from source 10.1.1.1 and source port 1389 to destination 10.2.0.0/16

 

permit tcp 10.2.2..0 0.0.255.255 host 10.1.1.1 eq 1389

will permit TCP traffic to destination ip 10.1.1.1 and destination port 1389 from source pool 10.2..0./16

 

So port number after source tells about source port and port number after destination tells about destination port

 

--Pls dont forget to rate helpful posts--

Regards,

Akash

4 REPLIES
Cisco Employee

 permit tcp host 10.1.1.1 eq

 

permit tcp host 10.1.1.1 eq 1389 10.2.2..0 0.0.255.255

Will permit TCP traffic from source 10.1.1.1 and source port 1389 to destination 10.2.0.0/16

 

permit tcp 10.2.2..0 0.0.255.255 host 10.1.1.1 eq 1389

will permit TCP traffic to destination ip 10.1.1.1 and destination port 1389 from source pool 10.2..0./16

 

So port number after source tells about source port and port number after destination tells about destination port

 

--Pls dont forget to rate helpful posts--

Regards,

Akash

New Member

Awesome ...!!! Thanks 

Awesome ...!!! Thanks 

New Member

But if it foe eg.Telnet

But if it is for eg.Telnet traffic..then how do we decide whether it is frm source side or destination side??wont it be telnet communication on both sides??

Super Bronze

See your posting: https:/

See your posting: https://supportforums.cisco.com/discussion/12554126/acl-concept#comment-10635031

126
Views
5
Helpful
4
Replies