IP space Planning

The network uses TCP/IP as the transport layer. Therefore, every active element in the network should have an address. Using a private IP version 4 range, enough addresses will be available. Using IP version 6 will be a future enhancement and is not yet fully implemented. So, as the IP network grows there is a need for not only planning the radio frequency space, but also planning the IP space. The IP range is assigned on the basis of the different postal (zip) code regions in the coverage area, combined with the population density and average income per head. Client machines are provided with the correct network information for the area they are in by a local DHCP server running on the (first) node (the access point) they are connecting to. The information provided by the DHCP server is the IP address to use, the netmask, the nameserver addresses and the default gateway.

Any two nodes in the backbone that are connected to one another by a point-to-point link use a /30 IP range (i.e. 4 IP addresses). This ensures that traceroute shows the logical network topology (no physical hops are missing because all packets must rise to the IP level, none are routed by MAC address). IP space that is used for numbering an interlink from node A to node B is assigned from a separate IP range; it should belong to neither geographical area A or B, as it is part of the backbone.