A network segment is its physically or logically isolated part. This, so to speak, is the main part of the global connecting systems. In other words, a segment is a collection of nodes that share a common transmission medium. Networks can be divided into many parts, and each of them can simultaneously be a subdivision of various communication systems.
Networks are divided into both physical and logical parts. A physical segment is a section separated from other parts by a bridge (switch), repeater (hub), router. That is, there is a division into parts using additional network equipment. This makes it easier to understand the construction of the entire communication environment.
A logical segment is a subnet resulting from partitioning the global communication system created on the IP protocol. At the same time, all of them have their own range of addresses, specified by the network mask and address, and are combined using switches and routers.
Communication devices used to communicate between segments arerepeaters and bridges. The former, passing information between parts of the network, do not analyze it. Bridges, when transmitting frames, can filter them or combine them.
There are several goals that can be achieved by splitting networks. If it is made taking into account groups in which the main part of the traffic is in one local segment, with the allocation of the necessary different bandwidth to them, then the network flow will be optimized.
Another result of this separation is increased reliability. If one network segment fails, the others can work normally.
Segmentation is also necessary to achieve security. By defining who has access to a given part, limiting access beyond it, they implement different levels of protection.
The main thing, when dividing the network into segments, is to think over everything well so that when all these goals are achieved, communication of all groups is at the required level.
The process of the network must be controlled. First, monitoring is performed, that is, data is collected about its functioning.
Checking the network, as well as segment analysis, consists in processing all the information received at this stage, conclusions about the possible causes of failures, requires mandatory human participation.
The technical means used for these purposes include agents of control mechanisms, expert, internal diagnostic and control systems, protocol analyzers, devices for diagnosing cable systems.
A segment is a simple logical connection. It allowssignificantly simplify the construction of networks with complex topology. After all, there is no need to think over global scenarios, it is enough just to set up inter-segment connections. For each separate part, the logic of work can be absolutely individual. All this greatly simplifies the work of network masters and allows them to create high-level hierarchical structures.
The study of segmented networks is a must for all professionals involved in networking and building local and wide area networks.
