Study identifies best cabling for 10 Gigabit Ethernet

Paul Boughton

Tyco Electronics' Amp Netconnect business unit is one of the companies supporting what is described as the world's first independent study of UTP (unshielded twisted pair) and STP (shielded twisted pair) systems for 10 Gigabit Ethernet (10GBase-T) communications, which has recently been completed by GHMT AG, a third-party test laboratory.

This comparative study, which evaluated two U/UTP and one F/UTP and two S/FTP systems from five market-leading vendors, is said to offer conclusive proof that the best cabling infrastructure system to support 10GBase-T and larger applications is shielded copper.

David Richens, UK senior systems application engineer for Tyco Electronics' Amp Netconnect business unit, comments: "With the growing demand for IP bandwidth and end-user-driven broadband services for transmitting huge quantities of data or multimedia entertainment files, there is a need to guarantee the performance of high-speed communications technologies like 10 Gigabit Ethernet. For the first time, the industry now has a detailed insight into these performance aspects, backed by detailed evaluation from a world-leading independent test house."

The tests were conducted 'live' using real 10GBase-T equipment and traffic in environmental conditions established in international Mice (mechanical, ingress, chemical and electromagnetic) classifications. They were conducted by GHMT AG, an independent test laboratory founded in 1992. GHMT is an ISO/IEC 17025 certified third-party laboratory and one of the world's leading cabling test houses. GHMT specialises in cabling and systems, EMC analysis and concepts, as well as wireless applications.

Key findings in the GHMT study include the fact that 10GBase-T is very noise-sensitive because of the higher transmission frequency and lower signal levels caused by more complex coding schemes. In this context, shielded systems offer high coupling attenuation and therefore extraordinary Anext (alien cross-talk) and EMC performance, whereas unshielded systems show significantly weaker Anext performance and coupling attenuation because of balance-only based noise reduction.

In the GHMT evaluation, unshielded systems failed four out of five electromagnetic immunity tests as specified by the international Mice definitions to describe different environmental levels. In contrast, shielded systems work with 10GBase-T 'by design,' UTP systems require an increased level of time-consuming and costly 'immunity installation' practices.

Full details of the study can be found at a dedicated web site: