This paper first motivates how advances in networking architectures and protocols can complement advances in optical communications research to increase the overall value of optical networks by enabling more applications. A review of existing optical networking solutions is then provided along with a classification of different types of optical networks. Finally, we show how single-hop and multihop wavelength-routed networks can be used efficiently for fast end-to-end file transfers, when these networks are equipped with a hardware-implementable signaling protocol, a routing protocol, and a simple transport protocol. 1 Introduction Advances in networking architectures and protocols are driven by both new inventions in communications technologies and new applications. The work presented in this paper describes new optical networking architectures and protocols enabled by recent advances in multi-channel Wavelength Division Multiplexed (WDM) communications. In Section 2, we describe some of the important optical communications components such as WDM multiplexers/demultiplexers, programmable Optical Add/ Drop Multiplexers (OADMs), Optical Crossconnects (OXCs), tunable and fixed transmitters, continuousmode and burst-mode receivers (tunable or fixed), amplifiers, and WDM passive star couplers.Besides these technological advances in optical communications components, optical fiber deployment is now finally reaching customer premises buildings, i.e., enterprise/multiple tenant buildings in metropolitan areas. Given that fiber was already deployed on long-haul lines (between cities/continents), end-to-end fiber connectivity is now available to many business users.To exploit this increasing reach of fiber and the capabilities of new optical communications components, new networking architectures and protocols are needed to enable a larger set of communications applications on optical networks. A number of network architectures have already been proposed and some even implemented. As a review, we provide a description/classification of these 1. This author was funded by CATT, Center for Advanced Technology in Telecommunications, Polytechnic University, New York.

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Alpha-s 2 casein has a significant influence on protein content in goat milk, and the technological properties important for cheese processing. Specific alleles (A, B, C, E and F) of the alpha (α) s2 -casein gene (CSN1S2) result in higher protein, casein and fat content, and improved coagulation properties, which are useful for improved cheese making. The aim of this study was to investigate the polymorphism and genetic variation of CSN1S2 in South African dairy goats, using DNA sequencing technology. Sixty dairy goats (20 Saanes, 20 British Alpine, and 20 Toggenburg) and 20 meat-type goats were sequenced with four primers to distinguish among the seven known alleles for α s2 -casein. A total of four alleles (A, B, C and F) for CSN1S2 were observed among the dairy-and meat-type populations with ten genotypes across the populations. The A allele and the AA genotype were the most frequent across the populations, with the favourable AC genotype being the most frequent (0.300) in the Saanen population. Two unique genotypes were detected in the Toggenburg (BB and BF) and one in the meat-type goats (CF). The results indicate moderate genetic variation for α s2 -casein in the South African goat populations (42.3-63.6%). Low positive F ST values suggest limited inbreeding. This study confirmed the presence of favourable alleles in the South African goat populations, indicating room for genetic improvement using directional selection for favourable genotypes.

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