TCP/IP Connections Introduction User Modes Connect Via... Addressing Subnet Masks Config Router Address DNS Search Paths Hosts File 802.3 Saving Configs Troubleshooting Tools For More Info Glossary updated: 08/11/97

Still More on Subnet Masks... Some possible subnet masks Remember that the subnet mask has to have a series of "1's" followed by a series of zeroes, to clearly delineate the network part of the address from the node part of the address. Only the following numbers are appropriate for subnet masks: 0, 128, 192, 224, 240, 248, 252, 255. Let's look at how these would work for subdividing a Class C address: 128 as in 255.255.255.128 or 11111111.11111111.11111111.10000000 192 as in 255.255.255.192 or 11111111.11111111.11111111.11000000 224 as in 255.255.255.224 or 11111111.11111111.11111111.11100000 240 as in 255.255.255.240 or 11111111.11111111.11111111.11110000 248 as in 255.255.255.248 or 11111111.11111111.11111111.11111000 252 as in 255.255.255.252 or 11111111.11111111.11111111.11111100 but not 255.255.255.254 (11111111.11111111.11111111.11111110)...why? Quiz! Which two devices are on the same subnet? 92.192.192.1 w/mask 255.255.255.0 92.192.192.2 w/mask 255.0.0.0 92.192.193.2 w/mask 255.255.255.0 92.192.192.128 w/mask 255.255.255.0 Here's Why... [Intro |UserModes |ConnectVia |Addressing |Subnet Masks |Config|Routers ]DNS |Search Paths |Hosts File ]802.3 ]Saving Configs ]Troubleshooting ]Tools ]More Info ]Glossary ]