O que (quem) é subnet address - definição

LOGICALLY VISIBLE SUBDIVISION OF AN IP NETWORK

Subnet address; Netmask; Subnetwork mask; Address mask; Subnet; Subnetting; Sub-net; Sub-network; Subnet Mask; IP range; Subnet Zero; User:Mancini/Subnetwork; IP Subnet Mask; Subnet Scheme; All zeroes subnet; Subnet mask tables; Subnets; Subnet mask; Net mask; Sub network; IP Subnetting; All-ones subnet; IPv6 subnetting; User:Klaver/IPv6 Subnetting; IPv6 Subnetting; IP subnet; Network subnet

subnet address

The subnet portion of an IP address. In a subnetted network, the host portion of an IP address is split into a subnet portion and a host portion using an address mask (the subnet mask).

address mask

<networking> (Or "subnet mask") A bit mask used to identify which bits in an IP address correspond to the {network address} and subnet portions of the address. This mask is often referred to as the subnet mask because the network portion of the address can be determined by the class inherent in an IP address. The address mask has ones in positions corresponding to the network and subnet numbers and zeros in the host number positions. (1996-03-21)

netmask

<networking> A 32-bit bit mask which shows how an {Internet address} is to be divided into network, subnet and host parts. The netmask has ones in the bit positions in the 32-bit address which are to be used for the network and subnet parts, and zeros for the host part. The mask should contain at least the standard network portion (as determined by the address's class), and the subnet field should be contiguous with the network portion. If a '+' (plus sign) is given for the netmask value, then the network number is looked up in the NIS netmasks.byaddr map (or in the /etc/netmasks) file if not running the NIS service. Unix manual page: ifconfig(8). (1995-01-30)

Wikipédia

Subnetwork

A subnetwork or subnet is a logical subdivision of an IP network.^: 1, 16 The practice of dividing a network into two or more networks is called subnetting.

Computers that belong to the same subnet are addressed with an identical most-significant bit-group in their IP addresses. This results in the logical division of an IP address into two fields: the network number or routing prefix and the rest field or host identifier. The rest field is an identifier for a specific host or network interface.

The routing prefix may be expressed in Classless Inter-Domain Routing (CIDR) notation written as the first address of a network, followed by a slash character (/), and ending with the bit-length of the prefix. For example, 198.51.100.0/24 is the prefix of the Internet Protocol version 4 network starting at the given address, having 24 bits allocated for the network prefix, and the remaining 8 bits reserved for host addressing. Addresses in the range 198.51.100.0 to 198.51.100.255 belong to this network, with 198.51.100.255 as the subnet broadcast address. The IPv6 address specification 2001:db8::/32 is a large address block with 2⁹⁶ addresses, having a 32-bit routing prefix.

For IPv4, a network may also be characterized by its subnet mask or netmask, which is the bitmask that, when applied by a bitwise AND operation to any IP address in the network, yields the routing prefix. Subnet masks are also expressed in dot-decimal notation like an IP address. For example, the prefix 198.51.100.0/24 would have the subnet mask 255.255.255.0.

Traffic is exchanged between subnetworks through routers when the routing prefixes of the source address and the destination address differ. A router serves as a logical or physical boundary between the subnets.

The benefits of subnetting an existing network vary with each deployment scenario. In the address allocation architecture of the Internet using CIDR and in large organizations, efficient allocation of address space is necessary. Subnetting may also enhance routing efficiency, or have advantages in network management when subnetworks are administratively controlled by different entities in a larger organization. Subnets may be arranged logically in a hierarchical architecture, partitioning an organization's network address space into a tree-like routing structure, or other structures such as meshes.

https://en.wikipedia.org/wiki/Subnetwork