GL Communications adds RFC 6349 TCP testing to PacketExpert 100G
GL Communications has expanded its PacketExpert 100G Ethernet Test Platform with ExpertTCP, an application designed to validate end-to-end TCP performance using the RFC 6349 methodology. The Gaithersburg, Maryland-based test and measurement vendor says the tool targets engineers working across enterprise, cloud, telecom, and data centre networks who need to verify application-layer performance before and after deployment.
The product is positioned as a response to a recognised gap in conventional benchmarking practice. Standards such as RFC 2544 and ITU-T Y.1564 test Layer 2 and Layer 3 throughput but do not exercise the full TCP stack. A network that passes those tests can still suffer degraded application performance due to misconfigured TCP receive windows, high baseline round-trip time, packet loss, or buffering effects upstream of the physical layer. ExpertTCP is intended to surface those hidden bottlenecks.
What the tool does
ExpertTCP automates the complete RFC 6349 workflow: Path MTU Discovery, baseline RTT measurement, Bandwidth-Delay Product calculation, TCP Receive Window optimisation, and throughput testing are executed in sequence after a single configuration pass. The application supports up to 16 simultaneous TCP connections on Gigabit and 10 Gbps Ethernet, and can run upstream, downstream, or bidirectional tests independently, reporting results per direction and per connection.
Real-time dashboards surface TCP Throughput, TCP Efficiency, Path MTU, Baseline RTT, BDP, TCP Receive Window, Transfer Time, retransmissions, and byte statistics. Engineers can run tests from a browser-based interface accessible on standard PCs, laptops, and tablets, or drive automated regression suites via a Python API. PDF and CSV exports are available for SLA verification and compliance documentation.
Two deployment modes are supported. In Single Device Mode a single PacketExpert 100G unit acts as both client and server across two Ethernet ports, suitable for local validation. Client-Server Mode uses two units as independent endpoints to test across network segments or geographically separated sites.
Vikram Kulkarni, Sales Director at GL Communications, said the tool "enables engineers to move beyond traditional packet-level benchmarking and evaluate how TCP applications perform across real networks."
Market context
Network performance testing is a mature but fragmented market, with established vendors including Spirent Communications, Keysight Technologies, and VIAVI Solutions competing across overlapping hardware and software categories. RFC 6349, originally published by the IETF in 2011, has seen renewed interest as enterprise and cloud operators seek tighter SLA assurance on high-speed links, particularly as 25G, 100G, and 400G Ethernet become standard fabric in data centres.
The move toward application-layer test coverage reflects broader pressure on network teams to demonstrate performance at the service level, not just the packet level. Regulators and enterprise procurement frameworks increasingly require documented SLA evidence as part of supplier qualification, and tools that automate RFC-compliant measurement reduce the manual overhead of producing that evidence.
GL Communications has not disclosed pricing or the number of existing PacketExpert 100G customers. The company's product catalogue spans voice quality testing and protocol simulation alongside Ethernet test hardware, positioning ExpertTCP as an incremental addition to an existing installed base rather than a standalone product launch. Analysts and buyers will be watching for benchmark data comparing ExpertTCP results with those produced by competing platforms before committing to procurement decisions.