Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

1998

Computer Sciences

University of Nebraska - Lincoln

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

Optimizing Amplifier Placements In A Multiwavelength Optical Lan/Man: The Unequally Powered Wavelengths Case, Byrav Ramamurthy, Jason Iness, Biswanath Mukherjee Dec 1998

Optimizing Amplifier Placements In A Multiwavelength Optical Lan/Man: The Unequally Powered Wavelengths Case, Byrav Ramamurthy, Jason Iness, Biswanath Mukherjee

School of Computing: Faculty Publications

Optical networks based on passive-star couplers and employing WDM have been proposed for deployment in local and metropolitan areas. These networks suffer from splitting, coupling, and attenuation losses. Since there is an upper bound on transmitter power and a lower bound on receiver sensitivity, optical amplifiers are usually required to compensate for the power losses mentioned above. Due to the high cost of amplifiers, it is desirable to minimize their total number in the network. However, an optical amplifier has constraints on the maximum gain and the maximum output power it can supply; thus, optical amplifier placement becomes a challenging …


Wavelength Conversion In Wdm Networking, Byrav Ramamurthy, Biswanath Mukherjee Sep 1998

Wavelength Conversion In Wdm Networking, Byrav Ramamurthy, Biswanath Mukherjee

School of Computing: Faculty Publications

Wavelength conversion has been proposed for use in wavelength-division multiplexed networks to improve efficiency. This study highlights systems challenges and performance issues which need to be addressed in order to incorporate wavelength conversion effectively. A review/survey of the enabling technologies, design methods, and analytical models used in wavelength-convertible networks is provided.


Optimizing Amplifier Placements In A Multiwavelength Optical Lan/Man: The Equally Powered-Wavelengths Case, Byrav Ramamurthy, Jason Iness, Biswanath Mukherjee Sep 1998

Optimizing Amplifier Placements In A Multiwavelength Optical Lan/Man: The Equally Powered-Wavelengths Case, Byrav Ramamurthy, Jason Iness, Biswanath Mukherjee

School of Computing: Faculty Publications

Wavelength division multiplexing (WDM) provides the ability to utilize the enormous bandwidth offered by optical networks, using today’s electronics. WDM-based optical networks employing passive-star couplers have been proposed for deployment in local and metropolitan areas. Optical amplification is often required in such networks to compensate for the signal attenuation along the fiber links and the splitting and coupling losses in the network. However, an optical amplifier has constraints on the maximum gain and the maximum output power it can supply; thus optical amplifier placement becomes a challenging problem. A simplifying assumption for analytical tractability requires that all wavelengths, present at …


Empirical Studies Of A Safe Regression Test Selection Technique, Gregg Rothermel, Mary Jean Harrold Jun 1998

Empirical Studies Of A Safe Regression Test Selection Technique, Gregg Rothermel, Mary Jean Harrold

School of Computing: Faculty Publications

Regression testing is an expensive testing procedure utilized to validate modified software. Regression test selection techniques attempt to reduce the cost of regression testing by selecting a subset of a program’s existing test suite. Safe regression test selection techniques select subsets that, under certain well-defined conditions, exclude no tests (from the original test suite) that if executed would reveal faults in the modified software. Many regression test selection techniques, including several safe techniques, have been proposed, but few have been subjected to empirical validation. This paper reports empirical studies on a particular safe regression test selection technique, in which the …


Ber-Based Call Admission In Wavelength-Routed Optical Networks, Debasish Datta, Byrav Ramamurthy, Helena Feng, Jonathan P. Heritage, Biswanath Mukherjee Jan 1998

Ber-Based Call Admission In Wavelength-Routed Optical Networks, Debasish Datta, Byrav Ramamurthy, Helena Feng, Jonathan P. Heritage, Biswanath Mukherjee

CSE Conference and Workshop Papers

Consider a wavelength-routed optical network in which nodes, i.e., multiwave length cross-connect switches (XCSs), are connected by fiber to form an arbitrary physical topology. A new call is admitted into the network if an all-optical lightpath can be established between the call’s source and destination nodes. Wavelength converters are assumed absent in this work.