Implementing network protocols at user level

摘要: Traditionally, network software has been structured in a monolithic fashion with all protocol stacks executing either within the kernel or single trusted user-level server. This organization is motivated by performance and security concerns. However, considerations of code maintenance, ease debugging, customization, simultaneous existence multiple protocols argue for separating implementations into more manageable libraries protocols. The present paper describes design implementation transport as libraries. authors begin motivating need placing their approach context previous work. They then describe alternative to organization, which implemented on Mach workstations connected not only traditional Ethernet, but also modern network, DEC SRC AN1. Based authors' experience, they discuss implications host-network interface overall system structure support efficient >