Branka Mikavica

Lightpath routing and spectrum allocation over elastic optical networks in content provisioning with cloud migration

In this paper, the problem of content provisioning over elastic optical network (EON) with possible cloud migration is addressed. We perform the analysis that encompasses the problem of content placement into cloud data centers together with lightpath routing and spectrum assignment in EON. We propose a novel mixed integer linear programming model to solve the considered optimization problem. Multiple attribute decision-making methods are used to determine the relevance of each criterion in the objective function. The developed model achieves appropriate placement of content groups into cloud data centers and determines the lightpaths depending on a given bandwidth demand for content provisioning, thus optimizing cloud migration, spectrum utilization and lightpath length, simultaneously. The model is evaluated in two realistic optical network scenarios: the medium-sized INT9 network and the Euro28 network topology. Extensive optimization experiments are performed and the analysis of the network resources utilization is provided.

Possibility of fractional calculus application for telecommunication traffic modelling

Frakcioni racun je oblast matematicke analize koja se bavi izucavanjem i primenom izvoda i integrala proizvoljnog reda. Ovom teorijom bavili su se mnogi poznati matematicari među kojima su Ojler, Riman, Liuvil, Abel i Furije. Predloženo je vise definicija za izracunavanje izvoda i integrala necelog reda. U ovom radu daje se pregled nekih predloženih definicija, kao i osnovne postavke frakcionog racuna sa posebnim naglaskom na mogucnostima njegove primene u domenu modelovanja telekomunikacionog saobracaja. Cinjenica je da frakcioni racun poslednjih decenija nalazi sve vecu primenu u raznim naucnim oblastima. Modeli zasnovani na frakcionom racunu pokazali su se korisnim u fizici, mehanici, elektrotehnici, biohemiji, medicini, ekonomiji, teoriji verovatnoce. U ovom radu analizira se mogucnost primene frakcionog racuna u modelovanju telekomunikacionog saobracaja. Istraživanja pokazuju da se karakteristike telekomunikacionog saobracaja na lokalnom i globalnom nivou u mreži, kao sto su samoslicnost i zavisnost u dugom opsegu, efikasnije mogu opisati pomocu frakcionog racuna umesto konvencionalnih stohastickih procesa. U radu su prikazani predloženi modeli zasnovani na frakcionom racunu koji modeluju fenomene prisutne u savremenim telekomunikacionim mrežama.

Benefits of retail-minus concept for access service price determination

This paper analyzes the possibility of retail-minus concept application at the market with one incumbent and one or more potential entrants. A comparative numerical analysis of access prices is presented, taking into account the widespread cost based concept and the retail-minus concept. Relevant parameter in determination of the access prices is a measure of substitutability of the offered services.