62. Glossary

ACL

Access Control List

API

Application Programming Interface

ASLR

Linux* kernel Address-Space Layout Randomization

BSD

Berkeley Software Distribution

Clr

Clear

CIDR

Classless Inter-Domain Routing

Control Plane

The control plane is concerned with the routing of packets and with providing a start or end point.

Core

A core may include several lcores or threads if the processor supports hyperthreading.

Core Components

A set of libraries provided by the DPDK, including eal, ring, mempool, mbuf, timers, and so on.

CPU

Central Processing Unit

CRC

Cyclic Redundancy Check

Data Plane

In contrast to the control plane, the data plane in a network architecture are the layers involved when forwarding packets. These layers must be highly optimized to achieve good performance.

DIMM

Dual In-line Memory Module

Doxygen

A documentation generator used in the DPDK to generate the API reference.

DPDK

Data Plane Development Kit

DRAM

Dynamic Random Access Memory

EAL

The Environment Abstraction Layer (EAL) provides a generic interface that hides the environment specifics from the applications and libraries. The services expected from the EAL are: development kit loading and launching, core affinity/ assignment procedures, system memory allocation/description, PCI bus access, inter-partition communication.

FIFO

First In First Out

FPGA

Field Programmable Gate Array

GbE

Gigabit Ethernet

HW

Hardware

HPET

High Precision Event Timer; a hardware timer that provides a precise time reference on x86 platforms.

ID

Identifier

IOCTL

Input/Output Control

I/O

Input/Output

IP

Internet Protocol

IPv4

Internet Protocol version 4

IPv6

Internet Protocol version 6

lcore

A logical execution unit of the processor, sometimes called a hardware thread.

KNI

Kernel Network Interface

L1

Layer 1

L2

Layer 2

L3

Layer 3

L4

Layer 4

LAN

Local Area Network

LPM

Longest Prefix Match

main lcore

The execution unit that executes the main() function and that launches other lcores.

master lcore

Deprecated name for main lcore. No longer used.

mbuf

An mbuf is a data structure used internally to carry messages (mainly network packets). The name is derived from BSD stacks. To understand the concepts of packet buffers or mbuf, refer to TCP/IP Illustrated, Volume 2: The Implementation.

MESI

Modified Exclusive Shared Invalid (CPU cache coherency protocol)

MTU

Maximum Transfer Unit

NIC

Network Interface Card

OOO

Out Of Order (execution of instructions within the CPU pipeline)

NUMA

Non-uniform Memory Access

PCI

Peripheral Connect Interface

PHY

An abbreviation for the physical layer of the OSI model.

pktmbuf

An mbuf carrying a network packet.

PMD

Poll Mode Driver

QoS

Quality of Service

RCU

Read-Copy-Update algorithm, an alternative to simple rwlocks.

Rd

Read

RED

Random Early Detection

RSS

Receive Side Scaling

RTE

Run Time Environment. Provides a fast and simple framework for fast packet processing, in a lightweight environment as a Linux* application and using Poll Mode Drivers (PMDs) to increase speed.

Rx

Reception

Slave lcore

Deprecated name for worker lcore. No longer used.

Socket

A physical CPU, that includes several cores.

SLA

Service Level Agreement

srTCM

Single Rate Three Color Marking

SRTD

Scheduler Round Trip Delay

SW

Software

Target

In the DPDK, the target is a combination of architecture, machine, executive environment and toolchain. For example: i686-native-linux-gcc.

TCP

Transmission Control Protocol

TC

Traffic Class

TLB

Translation Lookaside Buffer

TLS

Thread Local Storage

trTCM

Two Rate Three Color Marking

TSC

Time Stamp Counter

Tx

Transmission

TUN/TAP

TUN and TAP are virtual network kernel devices.

VLAN

Virtual Local Area Network

Wr

Write

Worker lcore

Any lcore that is not the main lcore.

WRED

Weighted Random Early Detection

WRR

Weighted Round Robin