When establishing VLANs using Cisco components (routers, switches, WAPs), is it best to assign each VLAN an entire network (i.e. VLAN1 =
192.168.1.0 /24, VLAN2 = 192.168.2.0 /24) or can a single network be subnetted to conserve addresses (example VLAN1 = 192.168.1.0 /26, VLAN2 = 192.168.1.64 /26, etc.) ?I know the initial reaction to this might be "You have all kinds of private address space to work with so why is this an issue? Just assign a network to each VLAN." The issue is that my company uses a central address registrar for private addressing and is stingy on letting too many networks get assigned for fear someday everything will be used up (I seriously doubt that will ever happen.) I feel I need 15 VLAN's across three offices so I was hoping to ask for 172.28.96.0 /20 which would yield 16 separate, continuous networks where I would then assign one network to each VLAN and still have a spare network. I do not have anywhere near 4096 hosts so yes, I am wasting addresses.
The question comes down to: Is a VLAN configuration even possible subnetting a single network, or should I push for separate networks for each VLAN for ease of configuration and keeping my sanity.
Thanks in advance for any ideas.