GL Communications Inc. has announced that its PacketExpert—a quad port Ethernet/IP tester—has been enhanced to support the RFC 6349 framework for TCP throughput testing.
To verify Ethernet/IP-based networks, current widely used standards are RFC 2544 or Y.1564. However, both these standards, meant for testing at Layer 2 or Layer 3 (Ethernet or IP layers), are not sufficient, because they do not cover testing at TCP layer. The new ExpertTCP performs bidirectional TCP throughput measurements in combination with another unit at the remote location (other end of the network), it acts as the TCP server, and it supports both upstream (client → server) and downstream (server → client) direction testing.
Jagdish Vadalia, a senior manager for product development at the company, said, “GL’s PacketExpert, both PacketExpert 1G and PacketExpert 10G, have been enhanced to support RFC 6349 based TCP throughput (ExpertTCP) test functionality.
“PacketExpert 1G has four 10/100/1000-Mb/s electrical/optical ports and PacketExpert 10G has two 10-Gb/s optical ports and two 10/100/1,000-Mb/s electrical/optical ports, and both are capable of bit error rate testing (BERT), smart loopback, RFC 2544 testing, record and playback, single-stream and multistream simulation of IP links and Impairments (IPLinkSim and IPNetSim), multi-stream traffic generation and analysis (PacketBroker), and Y.1564 testing (ExpertSAM).”
He added, “IP network operators and service providers need to verify that their networks are performing well and meet the Service Level Agreements (SLA) with the customers. To verify Ethernet/IP-based networks, current widely used standards are RFC 2544 or Y.1564. However, both these standards are meant for testing at Layer 2 or Layer 3 (Ethernet or IP layers). Though these tests are necessary, they are not sufficient, because they do not cover testing at TCP layer. Most web based applications like HTTP, FTP, E-mail, etc. run over TCP. Even many modern web applications like Facebook, YouTube, and the like use TCP. Even if service-provider networks are tested using RFC 2544 or Y.1564, customers may still face problems with TCP throughput.
“The TCP throughput may not match the throughput at the Ethernet/IP layer. This is because TCP throughput depends on factors like the end-node TCP window size, buffer size of intermediate network nodes, etc. Also, impairments like latency and packet drops cause TCP retransmissions, severely affecting the TCP throughput. So, there is a gap in the current testing methods and to cover the gap RFC 6349 frame work has been devised.”
He further explained, “ExpertTCP performs bidirectional TCP throughput measurements in combination with another unit at the remote location (other end of the network) that acts as the TCP server. Many real-world networks are not symmetrical. There may be significant differences between upstream and downstream directions.”
He added, “ExpertTCP supports both Upstream (Client → Server) and Downstream (Server → Client) direction testing. Bidirectional simultaneous testing/unidirectional testing can be done. Results are reported for both directions.”
http://www.gl.com/rfc-6349-based-tcp-throughput-testing.html
