INTENT-BASED SERVICE AUTOMATION FOR 5G CORE NETWORK FUNCTION SLICING

The techniques presented herein maintain network function (NF) resource adjacencies regardless of the shared or dedicated nature of the NF and independent of the segmentation of the NF\u27s cluster resources across geographic management domains. To achieve this, the techniques use intent-based networking models in order to create NF resources that facilitate the network slice creation and resource allocation. More specifically, the techniques utilize a Yet Another Next Generation (YANG) model representation of a network slice to facilitate creation and state management of all NFs associated with a network slice instance. The YANG model enables inter-site and intercluster adjacencies where cloud-native container network interface (CNI) communications is invalid. This also provides reference points for inter-domain orchestration between the mobility NFs, the underlying data center switching resources, and wide area network (WAN) transport slices

Gröbner Bases and digital design

The theory of Gröbner Bases have many practical applications. The methods can be efficiently implemented in a computer system. They can also be used to solve complicated systems of equations. This essay treats the theory behind Gröbner Bases, and its algebraic foundations. The essay also examines a possible application to the simplification of digital circuits.Validerat; 20101217 (root

A time constrained real-time process calculus

There are two important questions to ask regarding the correct execution of a real-time program: (i) Is there a platform such that the program executes correctly? (ii) Does the program execute correctly on a particular platform? The execution of a program is correct if all actions are taken within their execution window, i.e. after their release time but before their deadline. A program which executes correctly on a specific platform is said to be feasible on that platform and an incorrect program is one which is not feasible on any platform. In this thesis we develop a timed process calculus, based on the pi-calculus, which can help answer these questions. We express the time window in which computation is legal by use of two time restrictions, before and after, to express a deadline and a release time offset respectively. We choose to look at correctness through the traces of the program. The trace of a program will always be a sequence of interleaved internal reductions and time steps, because programs have no free names. We define the meaning of a feasible program by use of these traces. In particular we define the speed of a particular system as the ratio between work steps and time steps. Based on this calculus we show how the two questions above can be answered in terms of traces of the process calculus and prove the classical utilization limit for Earliest Deadline First scheduling holds.Godkänd; 2008; 20081010 (ysko

FIFO networking : punctual event-triggered networking

It is desirable to be able to combine ease of implementation of a network with the ability to analyze the properties of the network. In order to address this we present a MAC protocol where the network acts as a FIFO, and examine the resulting properties of the network using both a theoretical study of the waiting times and a simulation experiment. It turns out that this type of protocol would allows us to achieve real-time guarantees for an event-triggered system, as well as controlled jitter for message delivery. Further, temporal composability, and how to design a system using FIFO networking, is discussed.Godkänd; 2009; 20090923 (leijon

Multipurpose models for QoS monitoring

Telecom operators face an increasing need for service quality management to cope with competition and complex service portfolios in the mobile sector. Improvements in this area can lead to significant market benefits for operators in highly competitive markets. We propose an architecture for a service monitoring tool, including a time aware formal language for model specification. Using these models allows for increased predictability and flexibility in a constantly changing environment.Godkänd; 2007; 20070523 (leijon)</p

Rethinking network management solutions

Telecommunication network management solutions need to shift perspective from one of network element management to service management. Operators need a service view of their network, with automatic service-impact correlation. This requires some major changes in the underlying solutions: equipment vendors must improve the supplied management interfaces and network management solutions must implement a higher degree of automation and correlation with a service focus. One obstacle is the lack of models and formalism to describe topology and service structuresValiderad; 2006; 20061217 (ysko)</p

Propagation of location information in constrained type inference

The Timber type system is an extension of the classical Hindley-Milner type system, incorporating both qualified types and first class polymorphism. Since we also have subtyping, type errors in this system manifest themselves as unsatisfiable constraints rather than as non-unifiable types as in the Hindley-Milner system. In this thesis, we present a theoretical model for propagating the source of a constraint so that it can be presented to the user in case of an error. We also present examples from an implementation of our system for the Timber compiler. We propagate the location information by adding annotations to the syntax tree and then preserve that information as we build the predicates and types needed for type checking. We conclude that the approach to annotation taken here is one possible solution for the propagation of location information in constrained type inference.Validerat; 20101217 (root

SALmon : a Service Modeling Language and Monitoring Engine

To be able to monitor complex services and examine their properties we need a modeling language that can express them in an efficient manner. As telecom operators deploy and sell increasingly complex services the need to monitor these services increases. We propose a novel domain specific language called SALmon, which allows for efficient representation of service models, together with a computational engine for evaluation of service models. This working prototype allows us to perform  experiments with full scale service models, and proves to be a good trade-off between simplicity and expressive power.Godkänd; 2008; 20080922 (stewal)</p

Semantic Alarms

Functions Virtualisation (NFV) and Software Driven Networks (SDN) aggregate resources across multiple domains. This puts requirements on understanding the overall alarm status across these domains and dependencies between them. Current practice of low-quality alarm documentation and confusion around fundamental concepts like alarm states, alarm-types and the underlying protocols like syslog and SNMP traps makes it hard to create one unified alarm interface as part of the SDN API.If alarm interfaces for the various components were expressed in a more formal manner including dependencies and propagation between the alarms the NFV/SDN interface could automatically present an integrated alarm API as well as a synthesized alarm state across the virtualized functions.We present a novel approach to alarm interfaces by providing a formal alarm model together with a domain-specific language that allows us to specify both the alarm models and the constraints placed on the alarm models in a consistent manner. This means that we can verify the consistency of an alarm interfaces and automatically generate interfaces, multi-domain correlation and aggregated states.Godkänd; 2014; 20140110 (stewal