If you set the interface up as a point-to-multipoint, then all of the serials in the WAN should be in the same network/subnetwork.
You should still pay attention to your addressing in that it is considered good paractice to not waste address space, and to form the addresses such that you can summarize your individual networks when using dynamic routing protocols.
An example of waste would be to assign an entire Class C address range to a network that will never contain more than, say, five hosts (like the WAN ports to five locations).
In that case, you want to subnet down to a space that (for this example) only has seven addresses, which would be a 255.255.255.248 network mask for that subnet. The remaining subnets for that address block could be used for other small LANS or utility systems.
As scott pointed if your going to have P2MP links you can have them in same subnet but if your gonna use P2P links then instead of wasting the whole /24 subnet you can further break them into /30 for your serial links (which is 4 as per your post here).
And make use of the remaining ip space in all your locations based on the local lans requirement over there in those locations.
If I have a number of routers at different sites, Can I put the serial ip's all on the same subnet ? i.e I have 4 offices connected in series, Can I have say office 1 serial ip 192.168.1.1, office 2 192.168.1.2, office 3 192.168.1.3, etc etc ?
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...
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