Will existing test equipment be able to handle 100Gbit Ethernet?

The broadband speeds delivered by the 100Gbit Ethernet can be exploited by telecom and data communication networks alike. This technology will permit greater subscriber uptake of all manner of advanced multimedia services, while simultaneously helping operators to lower their overall running costs. It does, however, require major test equipment upgrades - thus setting a number of difficult challenges. Some of these challenges will be solely of a technological nature, however, with most industry analysts agreeing that demand for increased bandwidth will push way ahead of the expected revenues that can be generated for some time yet, there are also commercial obstacles that need to be overcome. But looking at it solely from the perspective of test engineers, what are the implications of migrating to the 100Gbit Ethernet infrastructure. As described in the IEEE 802.3ba specification, 100Gbit Ethernet utilises multi-wavelength parallel optical transmission lines to transfer very large quantities of data, in contrast to conventional serial methodologies which have been more limited in their data capacity. All four of the optical channels employed are capable of taking up to 25Gbit/s of data. These data streams are then converted into ten electrical lanes that can each carry 2 x 5Gbits. As it is founded on Internet Protocol (IP) technology, the boost in operational efficiency levels that can be realised by replacing existing network resources with ones that are 100Gbit Ethernet based presents operators with a more flexible framework that can support a far broader array of features and functionality, in addition to the high data rates witnessed. It is the move to an IP based architecture that necessitates a radical change to the test strategy being employed. In particular, the parallel topology of 100Gbit Ethernet can potentially have huge effects on transmission with regard to signal skew. As a result greater care and attention will be called here by test engineers. Furthermore, in order to being compliant with the IEEE 802.3ba standard, a bit error rate (BER) rate of 10-12 has to be maintained. If there is any divergence from this the test engineer will need to be able to uncover this and resolve the problem that has led to it. In addition, test procedures such as line interface testing, line-coding modulation testing, transmitter analysis and fibre characterisation will all need to be undertaken. To complicate matters further it will, for the foreseeable future still be necessary to test established communication protocols, like as SONET/SDH, 10Gbit Ethernet Ethernet and OTN. With 100Gbit Ethernet testing now moving out of the laboratory environment and into the field, as roll-out begins to ramp up, several new aspects must be given serious consideration. Field based test engineers must be in possession of highly portable, compact, lightweight and easy to operate instrumentation that can deliver result that exhibit the highest degrees of accuracy. The intuitive operation of such instrumentation is of prime importance. This means that the specified test process can be completed rapidly, with the risk of errors being made kept to an absolute minimum, so that additional costs are not accrued through having to redeploy engineers to repeat tests that were done incorrectly. Finally, so that different pieces of instrumentation do not need to be specified in order to cover 10 , 40 and 100Gbit Ethernet network technology, multi-protocol equipment is highly desirable. In response to this, several manufacturers have introduced products with the capacity to analyse all of these protocols. The appearance on the market of sophisticated, high performance 100Gbit Ethernet testers that can support both legacy and emerging technologies will facilitate the roll-out of next generation communication networks. There will still be questions about how such items should be sourced that need to be addressed though. Budgetary constraints can often make direct purchase difficult and so in some cases rental over a certain time period may prove to be better option. Equipment rental firms can now supply test engineers with the tools they need for implementing and maintaining complex IP-based communication networks using 100G Ethernet technology. Since rental can be dealt with as an operational rather than a capital expense, it does not require heavy upfront investment. It also means that on-going costs (such as insurance, finance repayments, repair, recalibration, etc.) can be taken out of the equation, as well as alleviating the threat of being left with redundant equipment. Livingston is one such rental company that has started sourcing 100G Ethernet test equipment, supplying operators and their contract partners with models that are technically capable of implementing this infrastructure. For example, back in August, it assisted in a new Guinness World Record being set, when DANTE (Delivery of Advanced Network Technology to Europe) attained the fastest ever rate for implementing multi-Terabit optical capacity - installing and activating 8 Tbits/s of long haul super-channel optical capacity in a mere 19mins. DANTE is responsible for the construction and operation high speed communication infrastructure for foremost research institutions - so that information and ideas can be shared. Its GÉANT network is the largest research and education communication network in Europe. Built on the DTN-X packet optical transport networking platform from Infinera, it has over 50million users located at 10,000 different scientific establishments across the continent (including the CERN particle physics research centre). It is vital that DANTE is in a position to bring additional capacity online as soon as it is needed. Validation of the record was carried out using an EXFO FTB-85100G 100Gbit Ethernet tester (which can cope with testing at full-line-rate Ethernet and IP packet generation at over 148million packets/s) and an EXFO FTB-5240S optical spectrum analyser (with wide dynamic range and high resolution) that had been sourced from Livingston. These items provided the breadth of functionality and high degree of repeatability needed to ensure accurate test results. In conclusion, the implementation of 100Gbit Ethernet technology will result in overall network complexity being markedly increased and the diversity of test procedures that need to be executed expanding significantly. The acquisition of high end test hardware for such undertaking, with hefty price tags certain to be involved, may prove problematic in this uncertain business environment. Consequently some companies are finding equipment rental to be a more attractive alternative to direct purchase - allowing them to avoid being exposed to the threat of having underutilised test equipment in stock as well as circumventing the array of unseen costs associated with equipment ownership. Reinier Truer is with Livingston