IP/VoIP Analysis & Simulation

IP/Ethernet Test Tool

PacketCheck™ - Software Ethernet/IP Tester

PacketCheck™ is a comprehensive PC based Ethernet / IP test tool with BERT and Throughput testing abilities. It is very easy to use as a general purpose network performance analysis tool for 10Mbps, 100Mbps and 1Gbps LANs and WANs.


Software Ethernet Tester


GL's enhanced PacketCheck™ is a comprehensive PC based Ethernet / IP test tool with BERT and Throughput testing abilities. It is a general purpose network performance analysis tool for 10Mbps, 100Mbps and 1Gbps LANs and WANs. Throughput up to 800 Mbps can be easily tested.

PacketCheck™ makes use of PC's network interface card (NIC) to transmit and receive Ethernet or IP packets over the network.

The application generates multi stream Ethernet/IP/UDP traffic with on-demand bandwidth (up to 500 Mbps) and measures end to end performance such as Bit Error Rate, Total Packets, Packet loss, Out of Sequence Packets, and Errored Packets. Additional features include transmission of pre-recorded file traffic, GTP traffic simulation, Bursty and Fixed IFG (Inter Frame Gap) traffic generation mode, Delay measurements, impairment generation, and BER testing capability with provision to generate PRBS patterns or user–defined test patterns.

Also included is a powerful Report Generation feature to view report in XML and PDF formats.

Product Videos

PacketCheck BERT Video
PacketCheck Multistream Video
PacketCheck Impairments Video
PacketCheck One-Way Delay Measurement Video

PacketCheck™ can operate on - Layer 1 (Physical), Layer 2 (Data Link), Stacked VLAN (Q-in-Q), Layer 2.5 (Stacked MPLS), Layer 3 (Network), and Layer 4 (Transport) of the OSI reference model.

Ethernet Tester at Layer 1 (Physical), Layer 2 (Data Link), Layer 3 (Network), and Layer 4 
     (Transport) of OSI model

PacketCheck™ at Layer 1 (Physical), Layer 2 (Data Link) with Stacked VLAN tag,
Layer2.5 (MPLS), Layer 3 (Network), and Layer 4 (Transport) of OSI model


  • Determine the maximum throughput and error rates in a LAN / WAN
  • Determine Round Trip Delay (RTD) with microsecond accuracy
  • Determine One Way Delay (OWD) between two NIC cards with microseconds accuracy
  • Test network infrastructure for dropped packets, errors, latency, and so on
  • Detect traffic overload
  • Test network behavior with real world traffic like IPTV, VoIP and more
  • Test CAT 6 / CAT 5 cables for efficiency

Main Features

  • Generate full duplex traffic at any of the four layers (Layer1, Data Link with stacked VLAN/ MPLS, Network, Transport) with on-demand bandwidth
  • Test Ethernet or IP/UDP traffic of up to 500 Mbps bandwidth
  • Customizable VLAN stacks up to 3 levels with headers such as VLAN Type, ID, and Priority
  • Customizable stacked MPLS layers up to 3 levels with headers such as Label, CoS, TTL
  • Test end-to-end performance, including:
    • Bit-error-rate testing (BERT) on layer 1, layer 2, layer 2.5, layer 3, and layer 4 with various measurements - Bit Error Rate, Sync Loss Count, Bit Error Count, and more
    • Throughput, packet loss, packet counts, and out of sequence packets
    • Errored packets
    • User definable impairment insertion
    • Independent measurements per stream
    • Start and stop each stream independently at any time
    • Add any number of streams at run time even if some streams have already started
  • Quickly configure hundreds of Ethernet/IP/UDP streams:
    • Create 100+ full-duplex streams per PacketCheck™ easily
    • Each stream can be configured as Transmit Only, Receive Only, or Transmit and Receive
    • Ability to copy from one stream to another (both one-to-one copy and one-to-many copy) to quickly configure multiple streams
    • Define unique MAC/IP addresses for each stream
    • Define separate Frame size/Rate for each stream
    • Customizable protocol headers like MAC Source/Destination address, Length/Type field, IP Source/destination address, and UDP Source/Destination Port
  • Confirm multi stream and multi destination connectivity among all nodes:
    • Generate multi-stream traffic with varying frame size, bandwidth, MAC, MPLS, IP and UDP parameters, payloads, and modes of operation
    • Control transmit and receive streams independently
    • Ability to resolve IP Address to MAC address (based on Address Resolution Protocol (ARP)) for all streams with a single click, so that all streams are configured properly before starting the test
    • Populate switch/router MAC tables and routing tables using the Resolve all streams feature before the starting the test to avoid unnecessary flooding
  • Multi-layer operation:
    • Independently define each stream to operate as Layer2 (Ethernet) or Layer3 (IP) or Layer4 (UDP)
    • For Layer3 or Layer4 streams, analyzes the received payload based on the IP or UDP length and ignore any MAC padded bytes added in transit
  • Bandwidth Control:
    • Define the frame size/rate to be generated for each stream Independently
    • Frame sizes from 22 bytes up to 1518 supported
    • Up to 500 Mbps total combined rate (all streams combined) is possible
    • Jumbo frames also supported
    • The transmission rate can be configured to operate in 2 modes – Burst mode or Inter Frame Gap (IFG) mode
    • In Burst mode, each stream's rate can be set in Mbps, Kbps, etc.
    • Burst mode tries to generate traffic with the configured rate, but also as smoothly and evenly distributed so that the Device Under Test (DUT) node buffers do not overflow due to a temporary spike in the peak traffic
    • In IFG mode, the Inter Frame gap in milliseconds can be configured. The estimated rate achievable based on the IFG and the frame size is displayed for user convenience
  • PRBS Pattern Generation/Verification of various patterns like QRSS 26-1, 29-1, 211-1, 215-1, 220-1, 223-1
  • User Defined test patterns – up to 24 bytes length
  • Simulate real-world traffic (such as IPTV, RTP) by transmitting packets using pre-captured GL proprietary HDL files
  • Generate various run-time impairments – insert/delete bytes, and byte level impairments
  • Use a full-featured version or a loopback only version (with address swapping) at node endpoints
  • Monitor performance per stream – throughput, Round Trip Delay (RTD), One Way Delay (OWD), total packets, packet loss, out of sequence frames, error frames, correct pattern frames, pattern sync status, bit error rate, sync loss count, error count etc.
  • Generate reports in XML or PDF formats

Ethernet BER Testing

GL's PacketCheck™ supports BERT testing at various levels -

  • Layer 1 (Physical layer) – Payload is made up of BERT patterns.
  • Layer 2 (Framed Ethernet layer) - Bit pattern is inserted as the Ethernet Payload.
  • Layer 2 with Stacked VLAN - Bit pattern is inserted as Ethernet Payload with VLAN tags.
  • Layer 2.5 (MPLS) - Bit pattern is inserted as MPLS Headers
  • Layer 3 (IP level) – Bit pattern is inserted as the IP packet payload.
  • Layer 4 (UDP level) – Bit pattern is inserted as the UDP packet payload.

At Layer 1

The physical layer of the OSI model is where data is physically moved across the network interface. At Layer 1 cables, hubs and repeaters are used to transmit data across the medium.

For Layer 1 BER testing, PacketCheck™ can test the basic data flow over the physical connection. Connect the two test PCs using an Ethernet cable as shown below:

BERT Test Setup at Layer 1 connected using Ethernet cable

BERT Test Setup at Layer 1 connected using Ethernet cable

At Layer 2

Testing at layer 2 involves the switches, bridges, or NICs as the DUT. The bridges, switches, and NICs handle physical addressing, packing data into frames, and sequencing data frames. Only the MAC addresses need to be configured for layer 2 testing.

GL's PacketCheck™ can test the basic data flow over the network. This test is performed in order to

  • Test the capability of the switch to handle frames at various bandwidths
  • Test the forwarding capacity of the switch
  • Measure the ability of the switch to deliver the frames in sequence
  • Verify incoming data by analyzing bit patterns of the received frames

Scenario 1 - Source & Destination PC in the same LAN, connected through a single switch

Ethernet BER Test Setup at Layer 2 connected through a single switch

Ethernet BER Test Setup at Layer 2 connected through a single switch

Scenario 2 - Source & Destination PC located at different LANs connected through multiple switches.

Ethernet BER Test Setup at Layer 2 connected through multiple switches

Ethernet BER Test Setup at Layer 2 connected through multiple switches

At Stacked VLAN Layer

Stacked VLAN ID feature is used to simulate Carrier Ethernet as shown below, where the SP VLAN ID is stacked on top of CE VLAN ID.

stacked vlan

Stacked VLAN simulating Carrier Ethernet

At Stacked MPLS Layer

Stacked MPLS (up to 3 levels) is supported. Various test combinations such as single MPLS, multiple MPLS, VLAN + MPLS can be tested for single and multiple streams.

Ethernet BER Test Setup at Layer 2 connected through multiple switches

Ethernet BERT Test Setup at stacked MPLS

At Layer 3/Layer 4

The Network Layer (Layer 3) uses routing technologies to connect various systems within a network or to connect multiple networks together through Gateways. In Layer 3 testing, packets are routed between the Source and Destination PCs based on both the IP address and MAC address. So, both the MAC address and the IP address have to be configured for Layer 3 testing.

The Transport Layer (Layer 4) provides end-to-end, error-free reliable data transfer. TCP and UDP are the most common Layer 4 protocols. For Layer 4 testing, source and destination UDP ports need to be configured in addition to MAC and IP addresses.

PacketCheck™ supports BER testing at Layer 3 as well as Layer 4.

Testing at Layer 3 using GL's PacketCheck™ can be accomplished as shown in the figure below. Here, two PacketCheck™ applications operate in separate IP networks and are connected through routers, which route the frames based on the IP addresses in the test frames. Since IP networks encompass various types of physical networks consisting of LAN and WAN links, there is lot of scope for packet modification, packet loss and out of order packets. GL's PacketCheck™ helps measure these metrics of the IP network.

Two test scenarios at Layer 3 / 4 are as depicted in the diagram where the information in layer 3 / layer 4 is transmitted through the network in packets.

Scenario 1 - Source & Destination PC are located within the same IP network, and hence are directly reachable.

Ethernet BERT Indirect Routing Test Setup at Layer 3/ Layer 4 within 
								the same IP network

Ethernet BERT Indirect Routing Test Setup at Layer 3/ Layer 4 within the same IP network

Scenario 2 - Source & Destination PC are located at different IP networks, and are connected through routers.

Ethernet BERT Indirect Routing Test Setup at Layer 3/ Layer 4 at 
								different IP networks

Ethernet BERT Indirect Routing Test Setup at Layer 3/ Layer 4 at different IP networks

At Layer 4 testing, UDP packets are sent. This testing is useful in cases where there are firewalls which can intervene at network boundaries to reject, pass or modify packets.

Modes of Operation

The MAC and IP addresses of the available NICs in a PC are displayed in the GUI. PacketCheck™ can be configured in Normal or Loopback mode.

  • In "Normal" mode, the application can perform either transmit (Tx), receive (Rx), or transmit and receive (Tx and Rx) functions on single or multiple streams.
  • In "Loopback" mode the packets received from the device under test (DUT) are transmitted back to the same device without modifying the pattern. This mode is used for RTD measurement.
Interface Selection and Details Settings

Interface Selection and Details Settings

MAC, MPLS, IP, UDP Layer-wise Parameters Configuration

All test parameters are configured through the GUI. Key parameters include the Layer/Direction selection, MAC, VLAN, MPLS, IP, UDP, payload, transmit and receive, delay measurements and various impairments settings PacketCheck™ is automatically set to Layer 1 BER testing by disabling other layers.

Interface Configuration Settings

Interface Configuration Settings

[Layer 2] - Ethernet

Here you can configure the source and destination MAC Addresses. In addition, user can specify the Length/Type field value. Users can enable VLAN up to 3 stacks and configure with the headers.

The following table gives the Length/Field values for the configured Layers (2/3/4)

Layer Configured Frame Size Configured Length/Type Field Value
Layer 2 60 (actual frame size = 64 bytes) 00-2E
Layer 2 (between 64 and 1514) (Hex Value of Configured Frame Size -14)
Layer 2 1514 (actual frame size = 1518 bytes) 05-DC
Layer 2.5 ANY 08-47
Layer 3 (IP) ANY 08-00
Layer 4 (UDP) ANY 08-00
Layer 2 MAC Configuration

Screenshot of Layer 2 (MAC) with Stacked VLAN Configuration

[Layer 2.5] - Stacked MPLS

Selecting MPLS enables MPLS layer for the test. If MPLS is selected MPLS header is inserted after Ethernet header, and higher layer is by default set to IP. PacketCheck™ supports MPLS/IP (i.e., selecting Layer 2.5 as MPLS and Layer3 as IP) only. In this case, IP header will be inserted after MPLS. If None is selected for Layer 2.5, it will be a normal Ethernet packet, without the MPLS header inserted.

layer2.5 mpls configuration

Screenshot of Layer 2.5 (MPLS) Configuration

[Layer 3] - IP

Here you can configure the source and destination IP addresses. Users can configure various IP header fields like TOS field, TTL field and protocol field.

Build MAC Header Automatically option provided for the user's convenience automatically builds MAC header for Layer 3/ Layer 4 testing.

Increment Identification option may be used to set the initial IP header identification value, which will be automatically incremented for the subsequent packets.

layer3 ip configuration

Screenshot of Layer 3 (IP) Configuration

[Layer 4] - UDP

Here you can configure the source and destination UDP ports.

layer4 udp configuration

Screenshot of Layer 4 (UDP) Configuration

Traffic (Payload) Configuration

Users can choose to insert various types of packets into the stream by enabling the sequence number format, magic pattern, PRBS patterns through predefined files, and user-defined fixed pattern of up to 24 bytes. Payload Transmission types also includes HDL File Transmission, a GL's proprietary Ethernet traffic capture format. In addition, to the captured packet, HDL file format stores additional information about the packet such as timestamp. Using HDL file for transmission allows user to generate various kinds of traffic like IPTV, VoIP etc., using captured traffic.

Layer 1 BER Testing supports only PRBS patterns through predefined files, and user-defined fixed pattern of up to 24 bytes.

Users are allowed to configure Frame size, Bandwidth, Inter Frame Gap (IFG) and transmission stop condition parameters during packet transmission. Users can specify frame size of fixed / random length, and define the transmission rate in Bit per second. The received frame details can be logged into a binary (*.bin), HDL, and also BERT files for each stream, which are used for diagnosis purposes.

payload settings

Tx & Rx Parameters

tx rx parameters

Screenshot of Tx and Rx Parameter Settings

Traffic Generation Mode

The HDL file transmission has necessitated PacketCheck™ to operate in 2 different modes. The traffic generation mode is common to all the streams.

  • Burst Mode - In this normal mode of operation, traffic is generated in bursts and the configured bandwidth is maintained, ignoring the IFG value. Here, the emphasis is to try and achieve the configured bandwidth for each stream. The resultant Inter Frame Gap varies because of the bursty nature of the traffic.
  • IFG Mode - In this Inter Frame Gap mode, traffic is generated frame-by-frame, and the configured IFG is maintained. The configured bandwidth is ignored. Here, the emphasis is on maintaining the IFG value between successive packets for each stream. The actual Bandwidth generated depends on the Frame Size and the configured IFG.
  • Traffic Generation Mode

    Traffic Generation Mode

Inter Frame Gap (IFG) option emphasizes on maintaining the Inter Frame Gap rather than the bandwidth during traffic generation for HDL files. There are 2 ways to configure Inter Frame Gap for HDL file transmission:

  • For "Take from HDL File" option, the timestamps stored within the HDL file is read. The Inter Frame Gap between the packets is computed from these timestamps. This allows the generated traffic to mimic the captured traffic as much as possible.
  • User can also configure the "IFG value", during which the timestamps read from the HDL file is ignored and frames are transmitted with this Inter frame Gap.

Mobile GTP Traffic Simulation

Using the “HDL File Playback” feature within PacketCheck™, the packet data can be carried as pre-recorded traffic files (GL's proprietary Ethernet traffic capture format *.HDL files) to destination points and the same can be verified at the receiving end, which can also be a PacketCheck™. This feature can be used GL’s Mobile IP Core traffic module (requires Additional Licenses) to simulate GTP traffic over UMTS or LTE network.

Generally, in an EPC network, are two types of data pipes can be found - Default Bearer (with non-guaranteed QOS) and Dedicated Bearer (with assured guaranteed QOS). The PacketCheck™ can be used with GL’s MAPS™ UMTS / LTE Simulators to encapsulate the generated packet data within GTP headers when transmitting through the gateways such as SGSN & GGSN, or SGW & PGW to verify the bearer allocation bandwidth at the end points. The packet data traffic generated at one end is received at the other end can be verified with various statistics such as packet loss, lost frames, bit error count, Tx Rx frames count and other traffic parameters.


Users can introduce impairments into the outgoing traffic using various impairment types and duration. Supports various types of impairments - DELETE BYTES, INSERT BYTES, AND, OR, & XOR. Impairments can be introduced at specific intervals or can be set to continuous insertion on each stream.

impairment settings

Screenshot of Impairment Types and Settings

Delay Measurements

PacketCheck™ can measure One-Way Delay (OWD), calculating the delay at the receiving end in µsec. OWD can only be correctly calculated on a single PC with 2 NICs running PacketCheck™ on each of them. Only a single license needs to be purchased in this scenario. OWD-Tx option embeds Tx Timestamp within a special OWD packet along with the normal stream data. OWD-Rx option receives and detects the special OWD packet.

Also, PacketCheck™ can be configured to measure the average Round Trip Delay [RTD] value of each packet in µsec. RTD is applicable to Tx_RX streams with DUT/ remote end configured in Loopback mode for RTD to work.

one-way delay measurement

Screenshot of One Way Delay Measurement Settings and Statistics

round-trip delay measurement

Screenshot Round Trip Delay Measurement Settings and Statistics

While the test is running, users can view statistics for each stream. These include bit error rates, throughput, lost or out of order frames, RTD and OWD.

Stream Specific Statistics:

  • Stream ID - ID of the streams as added in the configuration window
  • Stream Name - displays the name of the streams specified while adding in the configuration window
  • Mode - indicates mode of traffic as specified for each stream during configuration
  • Duration - per stream statistics displays the Duration for which the stream is running in "HH:MM:SS" format
  • Tx Frames - is the number of frames being transmitted for the stream configured in Tx and Tx_Rx mode
  • Tx Rate - gives total data rate at which the frames are being transmitted
  • Rx Frames - is the number of frames received for the streams configured in Rx or Tx_Rx mode
  • Rx Rate - gives rate at which the data are being received
  • Lost Frames - gives the count of total lost frames for that particular stream
  • Out Of Order Frames - gives the count of total out of order frames which are received for the particular stream
  • Pattern Error Frames - gives the count of total pattern error frames received on that particular stream. This is relevant for Fixed Pattern only
  • Good Frames - count of total frames with matching pattern received
  • Non-test Frames Received - count of all non test frames received on that stream. A received frame is said to be a non test frame if it does not match the Layer addresses properly
  • Bit Error Rate - this is relevant for PRBS patterns only. Displays the calculated Bit Error Rate for the PRBS pattern being received
  • Error Status - Status condition displays 3 states - IN_SYNC, NO_SYNC, NO_RX_DATA (when no data is received)
  • Sync Loss Count - display the number of time Sync loss has occurred. This is relevant for PRBS patterns only
  • Error Count - displays the number of times Error has occurred. This is relevant for PRBS pattern only
  • Round Trip Delay (RTD) - provides round trip delay measurement for the stream
  • One Way Delay (OWD) - provides one way delay measurement for the stream
  • UDP Checksum Statistics - On the receiving side of the statistics window, UDP Checksum Error Frames indicate how many packets are received with wrong UDP Checksum per stream

  • udp checksum statistics
  • Zero Checksum UDP Packet: Total number of UDP packets received with the checksum value ‘Zero’.

Common Statistics:

  • Rx Broadcast Frames – displays the total number Broadcast frames received.
  • Rx Unicast Frames – displays the total number Unicast frames received.
  • Rx IP Frames – displays the count of received IP frames encapsulated in another IP packet.
  • Rx UDP Frames – displays the count of received UDP frames encapsulated in IP packets.
  • Rx ICMP Frames – displays the count of received ICMP frames encapsulated in IP packets used in exchanging control messages.
  • Rx ARP Frames – displays the count of received ARP (Address Resolution Protocol) frames
  • Rx 64 Length Frames – displays the count of frames with 64 bytes length received.
  • Rx 65-127 Length Frames - displays the count of frames varying between 65 to 127 bytes length received.
  • Rx 128-511 Length Frames - displays the count of frames varying between 128 to 511 bytes length received.
  • Rx 512-1023 Length Frames - displays the count of frames varying between 512 to 1023 bytes length received
  • Rx 1024-1518 Length Frames - displays the count of frames varying between 1024 to 1518 bytes being received.

PacketCheck™ can generate reports at the end of every test. The reports include statistics, configuration information, NIC details, stream and aggregated statistics, and other test information. Reports can be generated in Portable Document Format (PDF), and Extensible Markup Language (XML) format with customizable headers, footers, comments and logos. User can also generate periodic reports during the test execution.


Report Generation Configuration


PDF Test Report

Item No. Item Description
ETH100 PacketCheck™
ETH200 Two PacketCheck™ applications
  Related Products
PXE100 PacketExpert™ 1G
PXN100 PacketExpert™ 10GX

* Specifications are subject to change without notice.

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