Examples involving 'Restoration algorithm'

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An example where restoration actions are planned reacting to network failures.

Network design - Algorithms

Example nameDescription
FA_EA_minCongestionPrecomputedRestoration.java

Find traffic routing which minimizes the average between the network congestion in the non-failure state, and the worst network congestion among any single link failure

Keywords: Evolutionary algorithm (EA), Flow assignment (FA), Restoration algorithm

Given a set of nodes and links, with their capacities, an offered traffic, and a set of admissible paths for each demand (given by the k-shortest paths in km for each demand, being k an user-defined parameter), this algorithm uses an evolutionary algorithm metaheuristic to find for each demand two link-disjoint routes: a primary route, and a backup route used for restoration. That is, the backup route is pre-computed, but it carries not traffic unless the primary route fails. The optimization target is minimizing the average between the network congestion in the non-failure state, and the worst network congestion among the single link failures.

FA_EA_minCongestionSingleFailureOSPF.java

OSPF routing that minimizes the average congestion between (i) the congestion when no failure occurs in the network, (ii) the worse congestion ranging the cases when one single SRG is failed.

Keywords: Destination-based routing, Evolutionary algorithm (EA), Flow assignment (FA), OSPF, Restoration algorithm

This algorithm computes the OSPF routing that minimizes the average congestion between (i) the congestion when no failure occurs in the network, (ii) the worse congestion ranging the cases when one single SRG is failed. If no SRGs are defined, congestion in (i) is returned. An evolutionary algorithm is implemented. Each solution is coded as an array of as many elements as links, storing the OSPF weight in each link. Details on the particular form in which the evolutionary operators are implemented can be seen in the source code. The returning design includes the routes defined by the OSPF weights, and an attribute per link with its OSPF weight

Resilience simulation - Provisioning algorithms

Example nameDescription
NRSim_AA_genericRestorationAlgorithm.java

Generic provisioning algorithm based on restoration

Keywords: MPLS, Restoration algorithm

Algorithm which implements several restoration mechanisms: path/subpath/link restoration, and fast restoration.

NRSim_AA_OSPF_pathRerouting.java

Reroute all traffic according to the ECMP rule

Keywords: OSPF, Restoration algorithm

This algorithm reacts to any resilience event (failure/restoration) trying to routing all the traffic according to the ECMP rule, using link IGP weights. These weights are not modified by the algorithm.

NRSim_AA_WDM_pathRestoration.java

WDM Fast Reroute

Keywords: Regenerator placement, Restoration algorithm, WDM

This algorithm implements a local lightpath restoration mechanism. Since it assumes that the WDM network requires regenerators/wavelength converters, if the input design does not contain them, the algorithm computes the requirements of regeneration/conversion for each lightpath.