5G is an enabler to several new use cases. To support all of them, the network infrastructure must be flexible and it should adapt to the different situations. This feature is powered by SDN, NFV, and Automation, three of the main pillars on which the 5G network is built.Traditional network management approaches may not be suitable for the 5G Core Network User Plane, which holds strict requirements in terms of latency and throughput. Therefore, Artificial Intelligence agents have been proposed to manage the 5G in a more efficient manner, delivering a more optimized allocation of the resources. This approach requires real-time monitoring of the data passing by the Core Network, a feature not standardized by the current protocols. In this thesis, the design of a monitoring protocol for the 5G Core Network User Plane has been studied, focusing on precise measurement of latencies. Then, a In-band Network Telemetry (INT) framework has been implemented on top of a User Plane Function prototype. The prototype is built on top of a novel User Plane implementation, based on chaining of atomic functions called micro-UPFs (µUPFs).While the main focus of this work has been latency measurement, packet counters, byte counters and Inter Packet Gap values can be collected from the framework, proving the main KPIs of a 5G User Plane. The INT framework has been implemented through two new µUPFs, one for updating the INT metadata and one for collecting them. These metadata are attached to the user packets as GTP-U extended header, maintaining compatibility with the standard protocol. Moreover, the implemented framework allows high flexibility through dynamic tuning of the parameters, providing mechanisms to reduce the amount of telemetry data generated and, thus, the system overhead.The framework has been tested on a physical setup of four server machines, abstracting a Core Network User Plane, connected with 10 Gbps NICs. In all the tests performed, the performances of the User Plane are affected by the new functionalities only when INT metadata are inserted very frequently. The results show that is possible to monitor the three main KPIs of a 5G User Plane without heavily limiting the system performances. / 5G är en möjliggörare för flera nya användningsfall: för att stödja dem alla måste nätverksinfrastrukturen vara flexibel och den ska anpassa sig till de olika situationerna. Denna funktion drivs av SDN, NFV och Automation, tre av de viktigaste pelarna som 5G-nätverket är byggt på.Traditionella nätverkshanteringsstrategier kanske inte passar för 5G Core Network, som har strikta krav när det gäller latens och genomströmning. Därför har Artificial Intelligence-agenter föreslagits att hantera 5G på ett mer effektivt sätt, vilket ger en mer optimerad fördelning av resurserna. Detta tillvägagångssätt kräver realtidsövervakning av data som passerar via Core Network, en funktion som inte standardiseras med de aktuella protokollen.I denna avhandling har utformningen av ett övervakningsprotokoll för 5G Core Network User Plane studerats med fokus på exakt mätning av latenser. Sedan har ett in-band Network Telemetry (INT) -ramverk implementerats ovanpå en prototyp för User Plane Function. Denna prototyp utnyttjade Chain Controllerarkitekturen, en ny användarplan-implementering baserad på kedjan av atomfunktioner som kallas µUPF.Medan huvudfokuset för detta arbete har varit latensmätning, kan paketräknare, byttäknare och Inter Packet Gap-värden samlas in från ramverket, vilket bevisar de viktigaste KPI: erna i ett 5G-nätverk. INT-ramverket har implementerats genom två nya µUPF, en för att uppdatera INT-metadata och en för att samla dem. Dessa metadata är anslutna till användarpaketen som GTP-U utökad rubrik, bibehållande kompatibilitet med standardprotokollet. Dessutom tillåter det implementerade ramverket hög flexibilitet som tillåter dynamisk inställning av parametrarna, tillhandahåller mekanismer för att minska mängden telemetri-data som genereras och därmed systemomkostnaderna.Ramverket har testats på en fysisk installation av fyra servermaskiner som abstraherar ett Core Network User Plane, anslutet med 10 Gbps NIC. I samtliga tester påverkas testbäddens prestationer av de nya funktionerna först när INT-metadata sätts in mycket ofta. Resultaten visar att det är möjligt att övervaka de tre huvudsakliga KPI: erna i ett 5G-nätverk utan att starkt begränsa systemprestanda.

This thesis is focused on methods for nodes localization in Internet using latency prediction in synthetic coordinates systems. Thesis also deal with methods, which latency prediction between nodes is based on other systems. Among such a methods particularly belongs King, which uses DNS (domain name service). Furthermore, thesis deal with relevance of overlay networks in latency prediction and their use for different services. Practical part of this thesis concentrates on method for latency prediction in synthetic coordinate system Global Network positioning. There were made two programs for counting coordinates of landmarks and hosts in this system. Measurements and calculations made in this thesis, are focused to determine accuracy of latency prediction of this method and their evaluation is made at the end of thesis.

This thesis deals with predicting the latency between two network nodes, such as the two stations, two servers or server and station. The main reason for adoption of effective latency prediction techniques is the elimination of network load caused by unnecessary repeated transmissios or by direct measurement of the latency. Of the many proposed methods of latency estimation, this thesis is focused on methods using artificial coordinate systems with primary focus on the Vivaldi algorithm. Characteristics of the latency prediction methods and properties of various coordinate systems used in practice are evaluated. The issue of the number of dimensions of space defined only by the latency matrix between nodes is also mentioned. Furthermore, some other systems, based on logical clustering of nearby nodes, are mentioned. Description of simulation software VivaldiMonitor developed as part of the thesis is included. The primary purpose is analysis of the behavior of overlay networks implementing Vivaldi algorithm with less than a few hundred nodes. The Vivaldi algorithm is assessed by several simulations carried out using the aforementioned software.