Coreografias de serviços Web representam uma forma mais escalável e flexível de compor serviços do que uma abordagem centralizada como a orquestração, e seu papel na integração e comunicação de sistemas de larga escala é vital para os objetivos da SOC (Computação Orientada a Serviços) e da Internet do Futuro. Atualmente coreografias de serviços Web possuem vários desafios de pesquisa, dos quais a qualidade de serviço (QoS) e o monitoramento de coreografias de serviçosWeb são linhas importantes. O objetivo deste trabalho é propor e implementar um mecanismo de monitoramento não intrusivo de coreografias de serviços Web baseado em SLAs (Acordos de Nível de Serviço) que especificam as restrições de atributos de QoS de maneira probabilística. Esta dissertação propõe um mecanismo para coreografias de serviços Web que: (1) define requisitos de QoS; (2) especifica contratos probabilísticos sobre parâmetros de QoS usando SLA; e (3) realiza um monitoramento não intrusivo de coreografias de serviços Web para detectar violações de SLA. / Web services choreographies are a more scalable and flexible way to compose services than a centralized approach like orchestrations, and its role in the integration and communication of large-scale systems is vital for the goals of SoC (Service Oriented Computing) and Future Internet. Currently,Web services choreographies have several research challenges. From all challenges, quality of service (QoS) and monitoring of Web services choreography are important research lines. The goal of this work is to propose and implement a mechanism for non-intrusive monitoring of Web services choreography based on SLAs (Service Level Agreements) that define constraints of QoS attributes in a probabilistic way. This thesis proposes a mechanism for Web services choreographies that:(1) defines QoS requirements; (2) specifies probabilistic contracts on QoS parameters using SLAs; and (3) monitors, non-intrusively, the enactment of Web services choreographies to detect SLA violations.

Coreografias de serviços Web representam uma forma mais escalável e flexível de compor serviços do que uma abordagem centralizada como a orquestração, e seu papel na integração e comunicação de sistemas de larga escala é vital para os objetivos da SOC (Computação Orientada a Serviços) e da Internet do Futuro. Atualmente coreografias de serviços Web possuem vários desafios de pesquisa, dos quais a qualidade de serviço (QoS) e o monitoramento de coreografias de serviçosWeb são linhas importantes. O objetivo deste trabalho é propor e implementar um mecanismo de monitoramento não intrusivo de coreografias de serviços Web baseado em SLAs (Acordos de Nível de Serviço) que especificam as restrições de atributos de QoS de maneira probabilística. Esta dissertação propõe um mecanismo para coreografias de serviços Web que: (1) define requisitos de QoS; (2) especifica contratos probabilísticos sobre parâmetros de QoS usando SLA; e (3) realiza um monitoramento não intrusivo de coreografias de serviços Web para detectar violações de SLA. / Web services choreographies are a more scalable and flexible way to compose services than a centralized approach like orchestrations, and its role in the integration and communication of large-scale systems is vital for the goals of SoC (Service Oriented Computing) and Future Internet. Currently,Web services choreographies have several research challenges. From all challenges, quality of service (QoS) and monitoring of Web services choreography are important research lines. The goal of this work is to propose and implement a mechanism for non-intrusive monitoring of Web services choreography based on SLAs (Service Level Agreements) that define constraints of QoS attributes in a probabilistic way. This thesis proposes a mechanism for Web services choreographies that:(1) defines QoS requirements; (2) specifies probabilistic contracts on QoS parameters using SLAs; and (3) monitors, non-intrusively, the enactment of Web services choreographies to detect SLA violations.

The Internet of the 21th century is a different version from the original Internet. The Internet is becoming more and more a huge distribution network for large quantities of data (Photos, Music, and Video) with different types of connections and needs. TCP/IP the work horse for the Internet was intended as a vehicle to transport best effort Connection oriented data where the main focus is about transporting data from point A to point B regardless of the type of data or the nature of path.  Information Centric Networking (ICN) is a new paradigm shift in a networking where the focus in networking is shifted from the host address to the content name. The current TCP/IP model for transporting data depends on establishing an end to end connection between client and server. However, in ICN, the client requests the data by name and the request is handled by the network without the need to go each time to a fixed server address as each node in the network can serve data. ICN works on a hop by hop basis where each node have visibility over the content requested enabling it to take more sophisticated decisions in comparison to TCP/IP where the forwarding node take decisions based on the source and destination IP addresses. ICN have different implementations projects with different visions and one of those projects is Named Data Networking (NDN) and that’s what we use for our work. NDN/ICN architecture consists of different layers and one of those layers is the Forwarding Strategy (FS) layer which is responsible for deciding how to forward the coming request/response. In this thesis we implement and simulate three Forwarding Strategies (Best Face Selection, Round Robin, and Weighted Round Robin) and investigate how they can adapt to changes in link bandwidth with variable traffic rate. We performed a number of simulations using the ndnSIMv2.1 simulator. We concluded that Weighted Round Robin offers high throughput and reliability in comparison to the other two strategies. Also, the three strategies offer better reliability than using a single static face and offer lower cost than using the broadcast strategy. We also concluded that there is a need for a dynamic congestion control algorithm that takes into consideration the dynamic nature of ICN. / 2000-talets Internet är en annan version av det ursprungliga Internet. Internet blir mer och mer ett stort distributionsnät för stora mängder data (foton, musik och video) med olika typer av anslutningar och behov. TCP / IP är arbetshäst för Internet var tänkt som ett fordon för att transportera best effort Anslutning orienterade uppgifter där huvudfokus handlar om att transportera data från punkt A till punkt B, oavsett vilken typ av data eller vilken typ av väg. Information Centric Nätverk (ICN) är ett nytt paradigmskifte inom nätverk där fokus i nätverket flyttas från värdadressen till innehållets namn. Den aktuella TCP / IP-modellen för transport av data beror på att etablera en anslutning mellan klient och server (s.k. end-to-end). I ICN begär klienten data med namn och begäran hanteras av nätverket utan att behöva gå till en fix serveradress eftersom varje nod i nätverket kan besvara en begäran med data. ICN arbetar på en ”hop by hop” basis där varje nod har överblick över det begärda innehållet, vilket gör det möjligt att ta mer avancerade beslut i jämförelse med TCP / IP, där den vidarebefordrande nodens beslut fattas baserat på källans och destinationens IP-adresser. Det finns olika implementeringar av ICN med olika visioner och en av dessa implementeringar heter Named Data Networking (NDN) och det är vad vi använder för vårt arbete. NDNs / ICNs arkitektur består av olika lager och ett av dessa lager är Forwarding Strategies (FS) där vi definierar de åtgärder vi vidtar på varje begäran / svar. I detta projekt implementeras och simuleras tre Forwarding strategier (Best Face Selection, Round Robin, och Weighted Round Robin) och undersöks hur de kan anpassa sig till förändringar i länkbandbredd med konstant och variabel trafikhastigheten. Vi utfört ett antal simuleringar med hjälp av ndnSIMv2.1 simulatorn. Vi drog slutsatsen att Weighted Round Robin erbjuder hög genomströmning och tillförlitlighet i jämförelse med de två andra strategierna.  De tre strategierna erbjuder även högre tillförlitlighet än att använda ett enda statiskt  interface och erbjuder lägre kostnad än att använda broadcast strategin. Vi konstaterade också att det finns ett behov av en dynamisk ”congestion control”-algoritm som tar hänsyn till ICNs dynamiska karaktär.