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IPLinkSim™ - IP WAN Link Emulator

Overview | Main Features | Applications
Working Principle | Buyer's Guide

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Generally today’s applications are intended to work on different networks such as enterprise networks, storage, cloud services, web services, ftp, audio/video streaming, etc.  Typically, such applications have a client and server components, communicating over a Wide Area Network (WAN) link, whether it be mobile browsing (http, ftp etc.), VoIP, IPTV over the public internet, or database access via the corporate intranet. Application developers can easily test their applications on a local LAN, but require testing with the realistic network conditions prior to live deployment. Conducting tests on real WAN links is expensive or simply not feasible in most cases. IP WAN Link Emulators help to test the performance of such WAN network-dependent applications by emulating the WAN conditions in a local setup easily and cost effectively.

pdf User's Guide
pdf Product Brochure
pdf CLI Brochure
WAN Link Emulation Presentation
PacketExpert™ Presentation
pdf Product List

IPLinkSim™ (IPN110) application is simple-to-use tool that simulates IP WAN (Wide Area Network) link and is available within a portable PacketExpert™ Ethernet / IP Test unit.  PacketExpert™ is a USB based portable Quad Port Ethernet / VLAN / MPLS / IP / UDP Tester with 4 Ports, 2 of which can be either Electrical or Optical (Port 2, Port 3), and remaining 2 are Electrical only (Port 1, Port 4). IPLinkSim™ supports WAN link simulation on Port 2, and Port 3 only.

A single PacketExpert™ - IPLinkSim™ can emulate a bidirectional IP WAN link with varying capacities from 10 Mbps to 1 Gbps for the electrical interfaces, and 1000 Mbps for the optical interface. Simply connect IPLinkSim™ unit in series with existing optical or electrical links, and introduce any impairment type to test the various applications in the lab prior to live deployment.

 IPLinkSim™ provides several such as user defined Bandwidth throttling, Congestion emulation, Latency, Packet Loss, Packet effects, Packet Corruption etc.  Bandwidth Throttling simulates slower WAN links like RS232/DSL/Modem/T1/E1/T3/E3 etc. This feature allows testing applications running in PCs which normally have 100/1000 Mbps interface but access to the outside internet or intranet over WAN is very slow. Congestion in the network can be emulated with generating an additional background traffic in addition to the traffic of interest. Latency can be used to recreate the constant or varying delay caused by various factors in the network.

Typically, WAN links suffer from Packet effects such as Packet Loss, cket Corruption, Packet Duplication and Packet reordering with additional burden on end to end applications to compensate for these impairments. Such frames are dropped at end points causing retransmissions. IPLinkSim™ provides features to emulate these Packet effects.

With additional licensing PacketExpert™ also supports Bert, Loopback, RFC 2544Wirespeed Record Playback, and ITU-T Y.1564 Testing - ExpertSAM™ applications.

Other variants of Ethernet/IP tester includes:

HD PacketExpert™ (PXE112 or PXE124) offers higher densities of 12/24 GigE ports form factor solution for testing GigE switches, routers and network conditions. This multi-device hardware unit incorporates all the features of a single quad port PacketExpert™ unit along with the necessary PC hardware with Windows® OS and remote accessibility via Ethernet Remote Desktop. The High-density PacketExpert™ supports up to 6 WAN links offering you multiple independent WAN links directly, with which you can compare and demonstrate application performance on different types of networks.

PacketExpert10G™ (PXG100) product provides comprehensive testing of 10G Ethernet/IP networks. It has two 10G optical ports, capable of BERT, Loopback and RFC 2544 test functionalities. The hardware interface also includes two 10/100/1000Mbps Electrical / Optical ports, supporting functionalities similar to the PacketExpert™ (PXE100).

PacketExpert™ also supports Command line Interface (CLI) to access all the functionalities remotely such as Bert,LoopbackRFC 2544Record Playback, ExpertSAM™,and IPLinkSim™ using TCL clients and MAPS™ CLI client/server architecture.

Main Features

  • Easy- to-use portable hardware based WAN Link Emulator.
  • Emulates 1 bidirectional WAN Link per IPLinkSim™ unit.
  • Each IPLinkSim™ unit supports dual electrical or optical interfaces per unit, with electrical ports supporting 10/100/1000 Mbps and optical ports supporting 1000 Mbps using SFP.
  • Emulate WAN link conditions separately and independently for each direction. Acts as a transparent bidirectional link or a simple Ethernet Bridge for easy integration with any test setup.
  • Easily monitor the bandwidth performance using live throughput graphs, and per-port or per-link statistics.
  • Check the stability or performance of the network with various real world impairments including Constant delay, Delay variation (Jitter), Congestion emulation, Packet Loss/Duplication/reordering, Logic error, and FCS error.
  • Bandwidth control (300 bps up to 1000 Mbps) to emulate various WAN link speeds (Modem, DSL, T1/E1/T3/E3/OC3/OC12 etc).
  • Supports transmission of Ethernet Pause frame with user-defined quanta used to throttle Ethernet link overload.
  • Supports Logic Error and FCS Error insertion within Ethernet packet.
  • Introduce bi-directional delay in milliseconds increments.
  • Command Line Interface for automated testing and remote accessibility.


  • Evaluate performance of enterprise-level, and bandwidth-sensitive applications prior to deployment
  • Test Audio, and Video quality on IP networks
  • Estimate bandwidth and QoS requirements

Working Principle

By default, IPLinkSim™ does not introduce any impairments, and IPLinkSim™ acts as a transparent bidirectional Ethernet link or a simple Ethernet bridge between 2 Ethernet end points. The links are emulated between Port 2 (P2) and Port 3 (P3).

P2 -> P3 is one link and in the reverse direction, i.e., P3 -> P2 forms the other link. By default, P2 and P3 work in pass-through mode, and pass all frames across to the other port. Frames arriving at P2 are carried over to P3 and frames arriving at P3 are carried over to P2.

Transparent Bidirectional Link (P2-P3)/(P3-P2)

On the emulated WAN links, you can choose to simulate the different link conditions (such as Bandwidth Control, Background Traffic, Latency, Error Insertion) emulating real-world scenarios.

PacketExpert(WAN Emulator) connecting  2 network end points

Impairments over P2->P3 and P3->P2 Link

Screen shot of Link Emulation

Check the stability or performance of the network with various real world impairments:

  • Bandwidth control (300 bps up to 1000 Mbps) to emulate various WAN link speeds (Modem, DSL, T1/E1/T3/E3/OC3/OC12 etc).
  • Congestion Emulation with Background traffic (% of total bandwidth )
  • Latency/Delay (0 milliseconds to 8 seconds – single delay, uniform, random distributions) to emulate various wired, wireless, and network elements.
  • Packet Loss (loss rate % of total packets 0–100%)
  • Packet Reordering (reordering rate (0-100%) with Min & Max Delay range)
  • Packet Duplication (percentage of total packets duplicated 0 - 100%)
  • Logic Error and FCS Error insertion (10-1 to 10-9 error rate) within Ethernet packet to emulate faulty network devices or interference

Link Statistics

This option provides real-time transmission statistics of the traffic over the emulated link (P2-P3)/(P3-P2) in each direction. The statistics parameters include Dropped Packets (Bandwidth Control), No. of Packets with Errors, Dropped Packets (Packet Loss), Duplicated Packets, Reordered Packets, and Background Traffic Bandwidth, for varying durations.

Screen Shot of Link Statistics

Link Throughput Graph

The graph displays the real-time Throughput of the link, plotted as rate against time, in the form of a line graph.  The Graph can be viewed for a single link or both the links together.

Screen Shot of Link Graph

Reference Links

Buyer's Guide:

Item No. Item Description

IPLinkSim™ WAN Link Emulator
(1 Gbps, 2 active ports)

PacketExpert™ - SA (4 ports)
PacketExpert™ - SA (12 Ports)
PacketExpert™ - SA (24 Ports)
PXE105 Wire speed Record /Playback
PXE106 ExpertSAM™
  Related Software
ETH100 PacketCheck™
PKS100 PacketGen™ (includes PacketScan™)
IPNetSim™ Handheld Network Impairment Generator
IPNetSim™ Handheld Remote Option
IPN501 IPNetSim™ - 1G
IPN505 IPNetSim™ - 1G Tablet
IPN510 IPNetSim™ - 10G

Refer PacketExpert™ webpage

* Specifications are subject to change without notice.

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