Linux Containers (LXC)  and Docker , as well as software-defined network (SDN) solutions , make extensive use of Linux namespaces, which allow you to define and use multiple virtual instances of the resources of a host and kernel. At this time, Linux namespaces include Cgroup, IPC, Network, Mount, PID, User, and UTS.
Network namespaces have been in the admin’s toolkit, ready for production, since kernel 2.6.24. In container solutions, network namespaces allow individual containers exclusive access to virtual network resources, and each container can be assigned a separate network stack. However, the use of network namespaces also makes great sense independent of containers.
Read more at ADMIN magazine