Cisco validating identity error
Nmap enables you to perform versioning (-s V) and OS detections (-O) separately or together as a combined command (-A): nmap –A 127.0.0.1 Starting Nmap 5.21 ( Interesting ports on 172.16.1.253: Not shown: 1707 closed ports PORT STATE SERVICE VERSION 22/tcp open ssh Cisco SSH 1.25 (protocol 1.99) 23/tcp open telnet Cisco router 80/tcp open http Cisco IOS administrative httpd 443/tcp open https?
If a host does not send this response, it is assumed that the port is open.
Service mapping tools are used to identify systems, remote services, and open ports.
These types of tools can be used to test a firewall rule base or response given different real or crafted IP packets.
There are also a number of free whitepapers and guides on the Internet.
The following sections discuss a few commercial and open source assessment tools that can be used to effectively audit Cisco networks.