Network Reference
The address blocks that hotspots, routers, Docker, VMs, VPNs and clouds use by default. Check a subnet before you set up a network, so it won’t collide with whatever someone plugs in later.
Check a subnet
Rules of thumb
- IPv4 LAN: pick a random
10.x.y.0/24. Skip10.0–10.10,10.42–43,10.64–127,10.88–89,10.96–111and10.244. - Avoid 172.17–172.31 if anything on the network runs Docker, WSL2 or Hyper-V.
- 192.168.x is crowded. Anything under ~
192.168.10is a router default somewhere, plus 43, 49, 50, 56, 64–71, 86, 88, 100, 122, 137, 178. - Don’t use
100.64.0.0/10for a LAN. ISPs (CGNAT) and Tailscale already live there. - IPv6: use
fd+ 40 random bits for your /48. Never usefc00::/8or a hand-pickedfd00::.
How crowded is each block?
The most power (EIRP) an 802.11 device may radiate in Australia, by band and channel, under the ACMA LIPD class licence. EIRP counts antenna gain, so a higher-gain antenna means turning the radio down.
Limits by band
Channels
Wide-channel numbers mark the centre of the whole block. Routers show the primary 20 MHz channel instead, e.g. "36, 80 MHz" not 42.
Weather radars near major cities
- Only C-band radars (5600–5650 MHz, channels 120–128) affect 5 GHz Wi-Fi. S-band radars don’t.
- Channels 116–128 are already banned for Wi-Fi in Australia.
- Within ~35 km of a C-band site (further with line of sight), skip the Avoid channels. DFS can drop your AP off them without warning.
- Safest near a radar: 36–48 or 149–165 (no DFS).
- Same channels for every site, as the Bureau doesn’t publish per-site frequencies. 35 km is the US radius for airport weather radars.
C-band: affects 5 GHz Wi-Fi
| City | Radar site | Area | Avoid | Radius |
|---|---|---|---|---|
| Melbourne | Broadmeadows | Northern suburbs, VIC | 100–112, 132–144 also 52–64 if DFS drops persist | 35 km further with line of sight |
| Adelaide | Sellicks Hill | Southern Fleurieu, SA | 100–112, 132–144 also 52–64 if DFS drops persist | 35 km further with line of sight |
| Perth | Perth Airport | Eastern suburbs, WA | 100–112, 132–144 also 52–64 if DFS drops persist | 35 km further with line of sight |
| Hobart | Mt Koonya | Tasman Peninsula, TAS | 100–112, 132–144 also 52–64 if DFS drops persist | 35 km further with line of sight |
| Hobart | Hobart Airport | Cambridge, eastern shore, TAS | 100–112, 132–144 also 52–64 if DFS drops persist | 35 km further with line of sight |
| Darwin | Berrimah | Eastern suburbs, NT | 100–112, 132–144 also 52–64 if DFS drops persist | 35 km further with line of sight |
| Darwin | Darwin Airport | Marrara, NT | 100–112, 132–144 also 52–64 if DFS drops persist | 35 km further with line of sight |
| Cairns | Saddle Mountain | Northwest of Cairns, QLD | 100–112, 132–144 also 52–64 if DFS drops persist | 35 km further with line of sight |
S-band: doesn’t affect Wi-Fi
| City | Radar site | Area |
|---|---|---|
| Sydney | Terrey Hills | Northern beaches, NSW |
| Wollongong | Appin | Macarthur, NSW |
| Newcastle | Newcastle | Hunter, NSW |
| Canberra | Captains Flat | Southeast of Canberra, NSW |
| Melbourne | Laverton | Western suburbs, VIC |
| Brisbane / Gold Coast | Mt Stapylton | Logan, between Brisbane and the Gold Coast, QLD |
| Brisbane | Marburg | West of Ipswich, QLD |
| Adelaide | Buckland Park | Northern plains, SA |
| Perth | Serpentine | Southeast fringe, WA |
| Townsville | Hervey Range | West of Townsville, QLD |
Sources: Australia’s weather radars (site list and band) and the Bureau of Meteorology’s RadComms 2022 talk (5600–5650 MHz). Each radar covers about 200–250 km.
mW ⇄ dBm
+3 dB doubles the power, +10 dB is ×10. 0 dBm = 1 mW, 20 dBm = 100 mW, 30 dBm = 1 W.