Don’t Get Caught With a Bottleneck in Your Network
9/7/2006
Source: Systimax Solutions (a CommScope company)
Communication complexity is increasing every year. Faster and faster networking enables organizations of all sizes to step up their pace of operation and can be a foundation for their competitive edge. If inadequate infrastructure restricts information flow, it could damage productivity and customer service, potentially impacting profits and the organization’s reputation. At first, it might appear that money can be saved by compromising on cabling in favour of more visible assets such as servers, PCs and software. But anyone making these choices should keep in mind that a cost saving on connectivity today has the potential of costing the organization tomorrow. Servers and PCs can be swapped in a matter of minutes or hours, and software re-instated overnight if a mistake is made. However, replacing critical cabling that is strangling the organization’s information flow often means taking up floors, ripping out miles of cable and replacing the contents of communication rooms. At the very least, some departments may need to relocate or otherwise be disrupted for weeks as the work is done. With computer and software prices falling while processing demands and network speeds continue to rise, the value of cabling installations with their integral labour and material content remains relatively constant. The right cabling should serve the organization well for 15 years or more, rather than just three to five. Over this longer period of time, it may support five generations of computers and three or more versions of software. Each new generation has the potential of multiplying loads on the network. Applications such as VoIP and grid computing, combined with mirroring of PC hard drives, network-based software upgrades and virus scans, are already making unprecedented and often unanticipated demands on bandwidth. Innovative applications are being introduced against a background of rapid growth in network traffic. Paper-based and face-to-face processes are constantly migrating onto networked PCs in the quest to increase efficiency and cut costs. Examples range from collaborative planning and development tasks that previously depended on travel to meetings to exchange of material via e-mail. The move to real-time collaboration and more visual or video-based technologies over the network makes quality-of-service vital. Levels of latency tolerated for e-mail and file transfer may not be robust enough to support collaborative applications effectively. This puts even more demands on the network infrastructure. Of all the LAN protocols, Ethernet is clearly the market favourite. As Ethernet has evolved to higher-speed forms, it addressed the needs of customers with a cost-effective, reliable solution to their data networking needs. Additionally, switched Ethernet networks have shown themselves to be extremely robust, performing over every physical media layer available, from twisted-pair cables to all types of fiber-optic cables. As the demand for bandwidth continues to increase, the next step in the evolution of Ethernet has appeared – 10 Gigabit Ethernet. In July 2006, the IEEE 802.3an Task Force is expected to ratify the standard for data transmission at 10 Gb/s over copper cabling and, if the past is any guide, this new standard will kick-start the move to the next generation of faster networks. Approval of the standard will give end-users confidence to invest in the higher performance applications that suppliers can offer. Inevitably, faster data transmission will also expose the limitations of the infrastructures currently being regularly installed. When published in 2002, the original specifications for 10G Ethernet were based primarily on fiber optics. With improved copper cabling technology now available, it promises to be a more cost effective alternative. It is for this reason that the IEEE set up its 802.3an Task Force to develop this technology further. New categories of cabling, specifically Category 6A and Class EA, are being prepared and drafted to offer specifiers a higher performance alternative to Category 6. Making the choice is similar to the dilemma when Category 6 superseded Category 5/5e - only now the stakes are higher. Looking forward to supporting 10G makes a strong case for Category 6A/Class EA copper cabling in new connections for datacenters as well as to the desktop. However, choosing the right Category/Class of cabling is just the first stage in cabling selection. Finding the right total solution can be just as vital since not all solutions verify conformance with specifications in the same manner. A cabling installation isn’t like a switch or PC. It can’t be fully tested in finished form at the factory since it needs to be installed in a real-world location. Added to this, the basic physics of transmission over twisted-pair cabling means the signals they carry induce interference in adjacent conductors and channels – known as “Crosstalk”. Controlling and predicting the composite crosstalk of the complete cabling channel rather than that of its individual cabling components is vital for the performance of a network connection. Including the latest phenomenon to hit the market - Alien Crosstalk, there are hundreds of parameters in a twisted-pair cabling channel that influence its performance. We believe that modelling all these variables with various cable lengths and connector combinations is the scientific way of ensuring that specifications are met from end-to-end in any channel. Without an advanced modelling system that accounts for all these parameters, such as the system developed at SYSTIMAX® Labs, cable and component In previous incarnations of Ethernet networks, problems with cabling were often less obvious. With 10 Gig the situation is different. It’s like connecting a high-speed pump to a pipe with a bottleneck. Winding up the power may not deliver the extra throughput everyone was anticipating – and then the hunt will be on for the ones responsible for skimping on the cabling! Smart datacenter administrators understand the importance of anticipating future needs when building their facility’s infrastructure.
design is difficult to optimize. In a real-world network, end-to-end connections may - or may not - meet specifications.