Classful Addressing | The concept that an IPv4 address has three parts–a network, sub-net, and host part–as defined by the sub-net mask and the Class A, B, and C rules for network classification. Classless Addressing | The concept that an IPv4 address has two parts–the prefix part and the host part–as defined by the mask, with no consideration of Class A, B, and C rules for network classification. Binary Masks | A string of binary numbers (1s and 0s) that are converted to create a specific output value. In the case of networking, this value is the sub-net mask. Dotted Decimal Notation (DDN) | A presentation format for sub-net masks in which 8 bits of binary numbers are converted into a decimal equivalent value. Decimal Mask | A sub-net mask that is done in dotted decimal notation. Network | A collection of computers, printers, routers, switches, and other devices that can communicate with each other over some transmission medium. Network Number | A number that user dotted decimal notation like IP addresses, but the number itself represents all hosts in a single Class A, B, or C network. Network Address | A number that uses dotted decimal notation like IP addresses, but the number itself represents all hosts in a single Class A, B, or C IP network. Network Broadcast Address | In IPv4, a special address in each classful network that can be used to broadcast a packet to all hosts in the same classful network. Numerically, the address has the same value as the network number in the network part of the address, and all 255s in the host octets–for example, 10.255.255.255 is the network broadcast address for the classful network 10.0.0.0. Network Part | The portion of an IPv4 address that is either 1, 2, or 3 octets/bytes long, based on whether the address is in a Class A, B, or C network. Infrastructure Mode | A mode of wireless network operations in which wiereless network clients send and receive data with an access point (AP), which allows the clients to communicate with each other using the wired infrastructure through the access point. Clients don’t send data to reach each other directly; the AP must receive the data from one client, and then send the data to the other WLAN client. Wi-Fi Alliance | An organization formed by many companies in the wireless industry (simply put, and industry association) for the purpose of getting multi-vendor certified compatible wireless products to market in a more timely fashion than would be possible by simply relying on standardization processes. Wi-Fi Protected Access (WPA) | A trademarked name of the Wi-Fi Alliance that represents a set of security specifications that predated the standardization of the IEEE 802.11i security standard. Wired Equivalent Privacy | An early wireless network security specification that used relatively weak security mechanisms, using only preshared keys and either no encryption or weak encryption. WLAN Client | A wireless device that wants to gain access to a wireless access point for the purpose of communicating with other wireless devices or other devices connected to the wired network.

The concept that an IPv4 address has two parts–the prefix part and the host part–as defined by the mask, with no consideration of Class A, B, and C rules for network classification.