Transport L4

Transport protocol that segments large diagnostic payloads across CAN frames using Single, First, Consecutive, and Flow Control PCI types…

End-to-end media transport for audio/video: sequence numbers, timestamps, SSRC, and payload type. Usually over UDP; profile and format sp…

Kernel-bypass networking model: queue pairs, memory regions, and work requests move data between registered buffers with minimal CPU. Com…

RDMA over UDP/IPv4/IPv6 on Ethernet: InfiniBand BTH follows the UDP header (port 4791). Routable across L3 with ECN/PFC/DCQCN for congest…

Lossless switched fabric with its own L2/L3 (LID/GID), subnet manager, and verbs transport (RC/UD/…). Credits, VLs, and partition keys pr…

Reliable, ordered byte-stream transport with ports, sequence/ack numbers, windowing, and congestion control. Three-way handshake and four…

ISO 13400 transport that carries UDS over TCP/UDP on vehicle Ethernet. Vehicle announcement/discovery, routing activation, and logical ad…

Modbus application PDUs carried over TCP port 502 with an MBAP header instead of serial address and CRC. Function codes and register maps…

CIP (Common Industrial Protocol) over TCP/UDP for industrial control, strongly associated with Rockwell ecosystems. Explicit messaging co…

REST-like protocol for constrained devices, typically over UDP, with confirmable/non-confirmable messages, tokens, and resource discovery…

SS7 connectionless and connection-oriented transport with global title translation (GTT) for number-based routing. It underpins TCAP and …

Stream Control Transmission Protocol — a multi-stream, multi-homed transport used heavily by SIGTRAN and some WebRTC data channels. Chunk…

SIGTRAN SCCP User Adaptation delivering SCCP-user data over SCTP without a full MTP3 stack on the application server. Common for TCAP app…

Companion control protocol to RTP providing sender/receiver reports, SDES identity, BYE, and extension feedback. Report intervals scale w…

Secure RTP/RTCP with encryption and authentication, keyed from SDES, DTLS-SRTP, or MIKEY. A rollover counter (ROC) and key derivation pro…

AAA and policy protocol that succeeds RADIUS in LTE/IMS and many 5G control functions. AVPs, application IDs (Gx, Gy, Cx, S6a, and others…

Session Traversal Utilities for NAT — binding requests discover reflexive addresses and keep NAT mappings alive for ICE. Attributes carry…

Traversal Using Relays around NAT — a STUN extension that allocates relayed transport addresses when direct peer paths fail. Permissions …

RDMA over TCP/IP using MPA framing with DDP and RDMAP layers. It traverses lossy networks better than RoCE but needs different NIC offloa…

Data Center Quantized Congestion Notification — RoCE congestion control that uses ECN marks and Congestion Notification Packets to rate-l…

NIC DMA path that reads and writes GPU memory directly, bypassing host bounce buffers for RDMA verbs. Requires peer-to-peer BAR mapping, …

Message Passing Interface — portable parallel messaging with point-to-point and collective operations across ranks. Implementations map t…

gRPC protocol for bulk Apache Arrow record-batch transfer with DoGet/DoPut and FlightDescriptors. Columnar data moves with minimal copies…

PCI Express — packetized serial I/O with lanes, LTSSM link training, and TLP/DLLP layers. Gen5/Gen6 rates and retimers define reach; ACS …

NVMe over Fabrics extends NVMe queues across RDMA, TCP, or Fibre Channel. Capsules map submission/completion queue entries over the fabri…

User Datagram Protocol — connectionless transport with ports and an optional checksum. It is the basis for DNS, RTP, QUIC, DHCP, and RoCE…

NVM Express — PCIe register and queue interface for SSDs with submission/completion queues, PRP/SGL data pointers, and admin commands. Pa…