Transport Features of the User Datagram Protocol (UDP) and Lightweight UDP (UDP-Lite)

On the Usage of Transport Features Provided by IETF Transport Protocols

“…Connection establishment, maintenance, and termination are therefore used to categorize transport primitives of connection-oriented transport protocols in pass 2 and pass 3. For this purpose, UDP is assumed to be used with "connected" sockets, i.e., sockets that are bound to a specific pair of addresses and ports [RFC8304]. Transport Feature: a specific end-to-end feature that the transport layer provides to an application.…”

“…This design process has started with a survey of the services provided by IETF transport protocols and congestion control mechanisms [RFC8095]. The present document and [RFC8304] complement this survey with an in-depth look at the defined interactions between applications and the following unicast transport protocols: Transmission Control Protocol (TCP), MultiPath TCP (MPTCP), Stream Control Transmission Protocol (SCTP), User Datagram Protocol (UDP), and Lightweight User Datagram Protocol (UDP-Lite). We also define a primitive to enable/disable and configure the Low Extra Delay Background Transport (LEDBAT) unicast congestion control mechanism.…”

“…We also define a primitive to enable/disable and configure the Low Extra Delay Background Transport (LEDBAT) unicast congestion control mechanism. For UDP and UDP-Lite, the first step of the protocol analysis --a discussion of relevant RFC text --is documented in [RFC8304].…”

Raising the datagram API to support transport protocol evolution

“…UDP is the simplest transport [1], offering a minimal protocol over IP, with service multiplexing with port numbers and optional checksums with best effort unreliable delivery. The UDP socket API provides a very simple interface for applications to send and receive datagrams, with the ability to control the options/parameters required to build applications [2].…”

“…This complicates application portability between platforms. Furthermore, the same setsockopt API is used to control features that are semantically not socket options [2]. For example, the IP_ADD_MEMBERSHIP option triggers an IGMP join of a multicast group, with semantic closer to that of connect().…”