NUSE is a library implementation of a network stack in userspace that allows new protocols and implementations to be added more quickly without modifying the kernel. It works by hijacking system calls related to networking at the library level, running the network stack code in a separate execution context using lightweight virtualization, and connecting to the network interface using options like
![Network Stack in Userspace (NUSE)](https://cdn-ak-scissors.b.st-hatena.com/image/square/5c24eb605020ec2a8b041c13056bddc113c9f763/height=288;version=1;width=512/https%3A%2F%2Fcdn.slidesharecdn.com%2Fss_thumbnails%2Fnuse-140925-hpcrouter-140929185115-phpapp01-thumbnail.jpg%3Fwidth%3D640%26height%3D640%26fit%3Dbounds)