Name: VIAVI TestCenter A3-400-QD-4 A3 400G 4-Port High Performance QSFP-DD Test Appliance
Brand: VIAVI
SKU: A3-400-QD-4

Overview

The VIAVI A3 400G Appliance (A3-400-QD-4) is a 2U rack-mountable QSFP-DD test platform with four ports. It is designed for high-scale control-plane and data-plane emulation. Supported speed modes are 400/200/100/50G with PAM4 encoding and 200/100/50/40/25/10G with NRZ encoding. Some modes are marked by VIAVI for upcoming software releases.

Speeds are enabled by license. A high-density 100G option breaks out each QSFP-DD port into 4xQSFP28, for up to 16 100G ports from one 2U unit. MACsec is supported on all ports.

Software and analytics

Tests can be created and run from three interfaces:

The TestCenter+ web UI
The Windows UI
Automation APIs

The TestCenter Model Context Protocol (MCP) Server is part of the VIAVI NITRO AI portfolio. It lets AI agents configure, execute, monitor and analyze tests using natural language. TestCenter IQ provides web-based analytics and reporting.

Key Features

Complete 400G Ethernet testing across QSFP-DD interfaces
Integrated Layer 2–3 validation on a single platform at full line rate
Precise, repeatable latency, jitter, throughput, and loss measurements
Validation of 100G/200G to 400G migration across multi-vendor ecosystems
Regression testing for software, hardware, and topology changes
4-port 2U high appliance for high-performance 400G testing
PAM4 and NRZ in one platform
MACsec supported on all ports
High-density 100G mode with up to 16 100G ports via 4xQSFP28 breakout
Protocol testing for L2/3 routing/switching and data center test cases
TestCenter MCP Server natural language interface for test configuration, execution, and analysis
Latency measurement with 2.5ns precision and resolution
19 scheduling algorithms for traffic emulation

Specifications

General

MSA interface	QSFP-DD
Operational modes	PAM4 400/200/100/50G; NRZ 200/100/50/40/25/10G* * Ordering availability and support for AN/LT, 50G PAM4, and NRZ speeds will be available in upcoming software releases
Per-port configurations	PAM4: 1x400G, 2x200G, 4x100G, 8x50G; NRZ: 1x200G, 2x100G, 4x50G, 2x40G, 8x25G, 8x10G * Available in upcoming software releases

Timing and Synchronization

Line clocking	Stratum-3 rated oscillator is the default time source Transmit line clock ± < 1 PPM on initial shipment; accurate to ± 4.6 PPM 15 years of operation
Frame time-stamp resolution	2.5ns
Appliance synchronization	± 20ns VIAVI-patented self-calibrating inter-chassis timing chain
Daisy chain	Up to 255 appliances

Layer 2-3 Generator and Analyzer

Number of paths/raw streamblocks	1024: 400G PAM4/200G PAM4/100G PAM4/200G NRZ/100G NRZ/50G NRZ/40G NRZ; 512: 50G PAM4/25G NRZ/10G NRZ
Frame transmit modes	Port-based (rate per port), Stream-based (rate per stream), Burst, Timed, Step Transmission, and manual scheduler mode, random frame size with unique seed
Min/max frame size (w/CRC)	60 to 16,383
Min/max Tx rates	1 packet per 1 second to 101% of line rate
Flow control	Priority Flow Control
Transmit timestamp resolution	2.5 ns With intra-chassis and inter-chassis synchronization
Supported encapsulations	Layer 2: Ethernet II, 802.1Q, 802.1ad, FCoE; Layer 3/4: IPv4, IPv6, TCP, UDP
Capture buffer size	8MB per port at all speeds
Latency modes	LIFO, LILO, FIFO or FILO Benchmark tests latency calculation methods
Route Insertion Table (RIT) entries per port	8M x 8 byte entries for all speeds Entries for dynamic label or random IP/MAC address assignments
RIT or list VFD	8 RIT insertions per stream and 10 VFD insertions per stream

Layer 1

QSFP/QSFP-DD interconnects	CR, SR, LR, FR, DR, PAM4, ZR, and ZR+ at multi-rate (400/200/100/50/40/25/10G)* Consult the factory for transceivers that consume more than 20 watts
PAM4 FEC	RS-544 (KP4) FEC all speeds
NRZ FEC	Clause 74 BASE-R FEC, Clause 91 RS-FEC, and Clause 108 RS-FEC NRZ support varies by module speed mode and license
AN/LT (enable/disable)	AN/LT supported for all speed modes* * Available in upcoming software releases

Physical and Environmental

Operating temperature range	50° to 95° F (10° to 35° C) With QSFP-DD transceivers rated up to 24W; above 24W the maximum is 84° F (29° C); minimum operating temperature 41° F (5° C)
Relative humidity	10% to 80% relative humidity (non-condensing)
AC input range	100-240 VAC
Max power draw	2100W
Unit installed weight	60 lb. (27.2 kg)
Shipping weight	89 lb. (40.4 kg)
Dimensions	17.1”W x 3.5”H x 30.0”L (43.4 cm x 8.9 cm x 76.2 cm)

Specifications are taken from the manufacturer's documentation. See the datasheet for complete and current values.

Options & Accessories

Option	Description
A3-400-QD-4-350A	A3 4-Port QSFP-DD 200G/100G/50G PAM4 Bundle — Availability in upcoming software releases
A3-400-QD-4-400A	A3 4-Port QSFP-DD 400G PAM4 Only
A3-400-QD-4-550A	A3 4-Port QSFP-DD 400G/100G/50G PAM4 Bundle — Availability in upcoming software releases
A3-400-QD-4-700A	A3 4-Port QSFP-DD 400G/200G/100G PAM4 Bundle
A3-400-QD-4-750A	A3 4-Port QSFP-DD 400G/200G/100G/50G PAM4 Bundle — Availability in upcoming software releases
A3-400-QD-4-825A	A3 4-Port QSFP-DD 400G/200G/100G/50G/40G/25G/10G PAM4 & NRZ Bundle — Availability in upcoming software releases
HWO-A3-400-QD-4-50G	50G PAM4 Hardware Speed Option for A3
HWO-A3-400-QD-4-100G	100G PAM4 Hardware Speed Option for A3
HWO-A3-400-QD-4-200G	200G PAM4 Hardware Speed Option for A3
HWO-A3-400-QD-4-400G	400G PAM4 Hardware Speed Option for A3
HWO-A3-400-QD-4-NRZ10G	10G NRZ Hardware Speed Option for A3
HWO-A3-400-QD-4-NRZ25G	25G NRZ Hardware Speed Option for A3
HWO-A3-400-QD-4-NRZ40G	40G NRZ Hardware Speed Option for A3
HWO-A3-400-QD-4-NRZ50G	50G NRZ Hardware Speed Option for A3
HWO-A3-400-QD-4-NRZ100G	100G NRZ Hardware Speed Option for A3
HWO-A3-400-QD-4-NRZ200G	200G NRZ Hardware Speed Option for A3
HWO-A3-400-QD-4-PORT	A3 QSFP-DD-8P Single Port Enablement
HWO-A3-QSFP-DD-4-4QSFP28	Hardware Option for A3-400-QD-4-T1S 400G PAM4 to 4x100G QSFP28 NRZ
SWO-A3-400-QD-4-MACSEC	MACSEC Software on A3-400-QD-4-T1S Appliance