Simple Linux IP Repeaters to Extend HomePlug Range
The most interesting result of our testing is, in addition to the repeater allowing communication beyond the HomePlug range, that it also enhances communications when two nodes barely can see each other. This is because the number of available HomePlug carriers increases.
For the sake of clarity, we assumed a configuration without an Internet connection in the parent subnet for our testing. First, we measured the response time and the throughput between two personal computers in a three-story building that could not see each other without the repeater in place. We tested both for UDP and TCP traffic. We used the Qcheck tool, a network-checking utility from Ixia. With a desktop-based repeater, we obtained response times for TCP and UDP traffic of approximately 100ms and throughput in the range of 2Mbps. This is realistic performance for medium-sized homes.
In a second test, we inserted the repeater between two computers that barely could see each other. The response time for both TCP and UDP doubled when inserting the repeater (50 to 100ms, approximately). However, the throughput grew from 1.5Mbps to 2Mbps.
We currently are testing the μClinux version on cards with a 100-BaseT Ethernet interface, such as the μCdimm ColdFire and the EV-S3C4530, both from Arcturus Networks.
Resources for this article: /article/8527.
Francisco J. González-Castaño is a professor with the GTI Group, Departamento de Ingeniería Telemática, Universidad de Vigo, Spain (www-gti.det.uvigo.es). He works in high-performance networking technologies and distributed computing, among other fields.
Pedro S. Rodríguez-Hernández is a professor with the GTI Group, Departamento de Ingeniería Telemática, Universidad de Vigo, Spain. He works with real-time and embedded systems.
Felipe J. Gil-Castiñeira is an assistant professor with the GTI Group, Departamento de Ingeniería Telemática, Universidad de Vigo, Spain. He works with wireless networking technologies and their applications.
Miguel Rodelgo-Lacruz is a researcher with the GTI Group, Departamento de Ingeniería Telemática, Universidad de Vigo, Spain. He works with high-performance networking technologies.
José Valero-Alonso recently received an Engineering degree from the GTI Group, Departamento de Ingeniería Telemática, Universidad de Vigo, Spain. He is interested in computer architecture and client-server systems.
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