This article presents an advanced framework for Dynamic Traffic Management (DTM), significantly extending our prior work on minimizing inter-domain traffic costs. The main extension enables cost optimization among multiple sending and multiple receiving domains. The mechanism works for volume and 95thpercentile tariffs. The main paradigm of DTM operation remains unchanged: DTM reacts dynamically on traffic changes on inter-domain links shifting some part of traffic (manageable traffic) from one link to another. This mechanism is based on flow load-balancing, it is centrally controlled by SDN controllers. It requires cooperation between operators receiving and generating traffic. Communication between domain operators is realized by SDN controllers (inter-domain SDN). DTM has been applied to inter-cloud communication for DCs located in different ISP domains. The experiments conducted in the hardware testbed, involving numerous sending and receiving sites, demonstrate that DTM can save up to 36% of the transfer cost.

This article introduces the concept, implementation and evaluation of Dynamic Traffic Management (DTM). This management mechanism minimizes traffic transfer costs on interdomain links. It works for volume and 95 h percentile tariffs. DTM reacts dynamically to traffic changes on inter-domain links shifting some part of traffic (manageable traffic) from one link to another. The management mechanism works in a distributed way. It requires cooperation between operators, namely Internet Service Providers (ISPs), receiving and generating traffic. Communication between ISPs is realized by SDN controllers (inter-domain SDN). DTM has been applied to intercloud communication for Data Centers (DCs) located in different ISP domains. Moreover, it is cloud-agnostic, i.e., DTM does not engage Cloud Service Providers (CSPs) into management procedures. Evaluation performed in the testbed shows that DTM is capable of decreasing ISP costs of transit traffic up to 29%.

In this paper, an innovative and adaptive BitTorrent-based peer-to-peer television (P2PTV) system is proposed and investigated. It is shown how end-users of such systems and Internet Service Providers (ISPs) may benefit from simultaneous usage of both (a) the recently standardized ALTO Protocol, and (b) Scalable Video Coding (SVC). The system description is followed by a thorough evaluation of the results gathered during the simulation experiments.

Information technology is widely used in processes vital to enterprises.Therefore, IT systems must meet at least the same level of security as required from the business processes supported by these systems.In this paper, we present a view on cybersecurity management as an enterprise-centered process, and we advocate the use of enterprise architecture in security management.Activities such as risk assessment, selection of security controls, as well as their deployment and monitoring should be carried out as a part of enterprise architecture activity.A set of useful frameworks and tools is presented and discussed.

Researchers who address the problem of application-level traffic optimization often consider only the simplest comparison scenario: (a) the case before the option to cooperate and optimize the service is enabled, and (b) the case in which all clients try to optimize the traffic. In this paper, the situations that a user may not wish to cooperate or that a user does not perceive the optimization possibility to be valuable enough to cooperate are taken into account. An analytical model for estimating the popularity of the cooperate-to-optimize option is derived. A method for calculating the time-dependent value of the predicted popularity is presented. The model is verified by simulation experiments.

The paper presents a concept of a rating algorithm aiming at overall peer-to-peer traffic reduction (and locality awareness) and decrease of load on costly links, thus diminishing operator's costs. The rating algorithm is not only performed by a sole Oracle, as is typically proposed, but its operation is also supported by a similar entity located in other domains. Due to this concept, a usually omitted fact that the inter-domain routes are asymmetrical is properly dealt with. Simulations performed on a real topology show the usefulness of the presented approach.

The paper proves that it is possible to optimize application-level multicast operation from the viewpoint of traffic flows. A modification of the FreePastry/Scribe application is proposed to enable cooperation with the IETF ALTO (Application- Layer Traffic Optimization) protocol. Consequently, the overlay topology is constructed taking into account the underlying network topology. The presented results show that costly traffic types can be reduced while the increase of the delay is not harmful.