govoril nisem o NAT port forwardingu...., ki jih imajo skoraj vsi routerji....
kr se subneta tiče
Class Address # of Hosts Netmask (Binary) Netmask (Decimal)
CIDR /4 240,435,456 11110000 00000000 00000000 00000000 240.0.0.0
CIDR /5 134,217,728 11111000 00000000 00000000 00000000 248.0.0.0
CIDR /6 67,108,864 11111100 00000000 00000000 00000000 252.0.0.0
CIDR /7 33,554,432 11111110 00000000 00000000 00000000 254.0.0.0
A /8 16,777,216 11111111 00000000 00000000 00000000 255.0.0.0
CIDR /9 8,388,608 11111111 10000000 00000000 00000000 255.128.0.0
CIDR /10 4,194,304 11111111 11000000 00000000 00000000 255.192.0.0
CIDR /11 2,097,152 11111111 11100000 00000000 00000000 255.224.0.0
CIDR /12 1,048,576 11111111 11110000 00000000 00000000 255.240.0.0
CIDR /13 524,288 11111111 11111000 00000000 00000000 255.248.0.0
CIDR /14 262,144 11111111 11111100 00000000 00000000 255.252.0.0
CIDR /15 131,072 11111111 11111110 00000000 00000000 255.254.0.0
B /16 65,534 11111111 11111111 00000000 00000000 255.255.0.0
CIDR /17 32,768 11111111 11111111 10000000 00000000 255.255.128.0
CIDR /18 16,384 11111111 11111111 11000000 00000000 255.255.192.0
CIDR /19 8,192 11111111 11111111 11100000 00000000 255.255.224.0
CIDR /20 4,096 11111111 11111111 11110000 00000000 255.255.240.0
CIDR /21 2,048 11111111 11111111 11111000 00000000 255.255.248.0
CIDR /22 1,024 11111111 11111111 11111100 00000000 255.255.252.0
CIDR /23 512 11111111 11111111 11111110 00000000 255.255.254.0
C /24 256 11111111 11111111 11111111 00000000 255.255.255.0
CIDR /25 128 11111111 11111111 11111111 10000000 255.255.255.128
CIDR /26 64 11111111 11111111 11111111 11000000 255.255.255.192
CIDR /27 32 11111111 11111111 11111111 11100000 255.255.255.224
CIDR /28 16 11111111 11111111 11111111 11110000 255.255.255.240
CIDR /29 8 11111111 11111111 11111111 11111000 255.255.255.248
CIDR /30 4 11111111 11111111 11111111 11111100 255.255.255.252
še enkrat c klasa je 255.255.255.0