Access List for blocking External IP

[techguy]

Hi,

Can I block external access to my router from telnetting/sshing?  I mean to say if telco gave me public ip address (either via static or dynamic) on my wan port. How can I restrict anyone to access my router by that public ip address. Thanks

[smitesh kharecha]

Just create a access-list, which only allows known IP address to login to the device and apply it to line vty 0 4.

HTH,

Smitesh

[techguy]

what do you mean by known ip address?. I think it must be a single deny command (explicitly or implicitly) on vty terminals

[smitesh kharecha]

Hi,

As for emergency situtation (for example, you want to access router, but you are at home) you might want to keep certain IP's allowed rather than blocking everything.

Regards,

Smitesh