NETGEAR FR314 Reference Manual page 144

Reference Guide for the Model FR314, FR318 and FV318 Cable/DSL Firewall and VPN Routers
Note: The number 192.68.135.127 is not assigned because it is the broadcast address
of the first subnet. The number 192.68.135.128 is not assigned because it is the network
address of the second subnet.
The following table lists the additional subnet mask bits in dotted-decimal notation. To use the
table, write down the original class netmask and replace the 0 value octets with the dotted-decimal
value of the additional subnet bits. For example, to partition your Class C network with subnet
mask 255.255.255.0 into 16 subnets (4 bits), the new subnet mask becomes 255.255.255.240.
Table B-1. Netmask Notation Translation Table for One Octet
Number of Bits
1
2
3
4
5
6
7
8
The following table displays several common netmask values in both the dotted-decimal and the
masklength formats.
Table B-2. Netmask Formats
Dotted-Decimal
255.0.0.0
255.255.0.0
255.255.255.0
255.255.255.128
255.255.255.192
255.255.255.224
255.255.255.240
255.255.255.248
B-6
Dotted-Decimal Value
128
192
224
240
248
252
254
255
Masklength
/8
/16
/24
/25
/26
/27
/28
/29
Networks, Routing, and Firewall Basics