ip subnet zero

stanley4le

how the h3ll does this work ?

Noods

http://www.cisco.com/warp/public/105/40.html

dissolved

turn it on by ip-subnet zero in config mode

example


Router (gateway)
|
| <

---

192.168.10.0 /30
|
Firewall

This gives us 2 usuable addresses. Which is the usual gig for connecting infrastructure devices. One for the router's internal interface. One for the firewalls external interface. The usuable IPs are 192.168.10.1 and 192.168.10.2. 192.168.10.0 is the network address. 192.168.10.3 is the broadcast address.

If we didnt have ip subnet zero support, we wouldnt be able to use that address space. We would have to start on 192.168.10.4. (192.168.10.4 is network, 192.168.10.5-6 are usuable addresses, 192.168.7.0 is broadcast)