I have a LAN with the IP scheme 192.168.5.x connected via MPLS and VPN to multiple other physical sites with individual subnets 192.168.1.x, 192.168.2.x, 192.168.3.x and 192.168.4.x. Subnet mask is 255.255.255.0 for all.
I need to increase available DHCP addresses of just the 5.x network, and allow the other subnets to continue to communicate with IPs on the 5.x network.
Is it better to:
1) change the subnet mask on 5.x to 255.255.255.254? I believe that will then increase the available DHCP to include 192.168.6.x range as well. Correct?
2) Set up a separate 6.x network and tie it into the 5.x (and other subnets) using a router?
I would prefer the first option, but will that have an effect on traffic speed across the LAN and the WAN? Will the 6.x addresses be able to communicate with 1.x and 2.x etc...? Or does it require a routing scheme update on the Cisco site to site routers?