I would like to know if there is anyway to tell how many devices are are being translated by a NAT device that I have no administrative control over from the outside. For example, if I am an ISP and want to know if a business or residential customer is re-routing the connection multiple times.
My impression is that if you sniff the line you can't tell because one inside device may be using multiple applications with different port numbers. I have been told that there may be a way to check with MAC addresses but I didn't think a NAT or firewall kept any record of MAC addresses.
There is no way how to check how many computers are behind NAT device.
To check what MAC addresses are used on the line between your and customer's router simply type "show ip arp". But there will be only MAC addresses which are on segments directly connected to your router.
By sniffing traffic on the line you can only guess how many computers are behind NAT device. For example count simulateous connections from NAT device to internet with destination port 80. Unfortunetaly it is very inaccurate...
We are pleased to announce availability of Beta software for 16.6.3.
16.6.3 will be the second rebuild on the 16.6 release train targeted
towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are
looking for early feedback from customers befor...
Introduction Featured Speakers Luis Espejel is the Telecommunications
Manager of IENova, an Oil & Gas company. Currently he works with Cisco
IOS® and Cisco IOS XE platforms, and NX to some extent. He has also
worked as a Senior Engineer with the Routing P...
In this session you can learn more about Layer 3 multicast and the best
practices to identify possible threats and take security measures. It
provides an overview of basic multicast, the best security practices for
use of this technology, and recommendati...