| A | B |
|---|
| segment | Section of a network that is bounded by bridges, routers, or switches |
| router | Network layer device that uses one or more metrics to determine the optimal path along which network traffic should be forwarded. It forwards packets from one network to another based on network layer information. |
| address | Data structure or logical convention used to identify a unique entity, such as a particular process or network device. |
| IP (Internet Protocol) | Network layer protocol in the TCP/IP stack offering a connectionless internetwork service. Provides features for addressing, type-of-service specification, fragmentation and reassembly, and security. |
| broadcast address | Special address reserved for sending a message to all stations. |
| subnetwork | networks arbitrarily segmented by a network administrator in order to provide a multilevel, hierarchical routing structure while shielding this segment from the addressing complexity of attached networks. |
| subnet mask | 32-bit address mask used in IP to indicate the bits of an IP address that are being used for the subnet address |
| 2 ^ 3 | 8 |
| 2^4 | 16 |
| 2^5 | 32 |
| 2^6 | 64 |
| 2^7 | 128 |
| 2^8 | 256 |
| 14 usable subnets | borrowed 4 bits |
| 6 usable subnets | borrowed 3 bits |
| Class A IP address range | 0 - 126 |
| Class B IP address range | 128 - 191 |
| Class C IP address range | 192 - 223 |
| Class A IP address | used for large organizations |
| Class B IP address | used for moderately sized organizations |
| Class C IP address | used by small organizations |
| Subnet mask for 125.64.0.0 / 11 | 255.224.0.0 |
| Subnet mask for 131.25.128.0 / 18 | 255.255.192.0 |
| Subnet mask for 201.64.128.32/ 28 | 255.255.255.240 |
