> > Why are you asking these questions? What's your ACTUAL issue? > > > > IIRC, last year my ISP gives me 8 IPv4, they said the first is network > addr, the last is broadcast addr, then I have to calculate the netmask by > myself.
Well, they told you the additional necessary information: 8 addresses. 2^3 = 8 32 - 3 = 29 They gave you a /29. The netmask is 255.255.255.248 The package you want to install is sipcalc: $ sipcalc 123.234.22.1/29 -[ipv4 : 123.234.22.1/29] - 0 [CIDR] Host address - 123.234.22.1 Host address (decimal) - 2078938625 Host address (hex) - 7BEA1601 Network address - 123.234.22.0 Network mask - 255.255.255.248 Network mask (bits) - 29 Network mask (hex) - FFFFFFF8 Broadcast address - 123.234.22.7 Cisco wildcard - 0.0.0.7 Addresses in network - 8 Network range - 123.234.22.0 - 123.234.22.7 Usable range - 123.234.22.1 - 123.234.22.6 -dsr-
