----- On Aug 9, 2021, at 9:22 AM, Masataka Ohta mo...@necom830.hpcl.titech.ac.jp wrote:
Hi, > It should be 14M. Just for fun, I did the math. A total of 16,777,216 /24s fit in 32 bits. Take away all the reserved space as per IANA (this is 1,266,696 /24s, see below), and we end up with 16,777,216 - 1,266,696 = 15,510,520 potential /24 advertisements. The largest FIB table I have seen (hi Jim!) was 3,563,546 routes in hardware. This was in a lab environment, of course. Thanks, Sabri https://www.iana.org/assignments/iana-ipv4-special-registry/iana-ipv4-special-registry.xhtml Subnet Number of /24s 0.0.0.0/8 65536 10.0.0.0/8 65536 100.64.0.0/10 16384 127.0.0.0/8 65536 169.254.0.0/16 256 172.16.0.0/12 4096 192.0.0.0/24 1 192.0.2.0/24 1 192.31.196.0/24 1 192.52.193.0/24 1 192.88.99.0/24 1 192.168.0.0/16 256 192.175.48.0/24 1 198.18.0.0/15 512 198.51.100.0/24 1 203.0.113.0/24 1 240.0.0.0/4 1048576 Total reserved 1,266,696
