You cannot use it for a 2600. Also NM-1FE-TX is an end of sale product from cisco. These will be replaced by NM-1FE2W. For 2600, you can use NM-16ESW which is a 16 port ether switch module. But all these ports will be considered as s switched port and not individual ports of the router (not routed interface). You cannot assing ip addresses to each of these interfaces, like you do for a routed interface.
Kpps means kilo packets per second. kilo = 10 exp 3.
So its a unit of measurement of the rate at which the router can switch packets. Its definitely a measure of router throughput. if the throughput for example, is defined as 10000 kpps, it can switch 10000 * 10 exp 3 packets in one second. The router processor has the capability to switch these many packets in 1 second.
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 custome...