Background Description

A PON network is a point-to-multipoint network which uses fiber cables as physical medium. It is for example used by telecom operators to provide high-speed internet access to their end-customers via a fiber connection. Traffic send by the end user into the network is called upstream traffic (e.g. to upload a photo). Traffic from the network towards the end user is called downstream traffic (e.g. to download a website).  On the fiber, the optical wavelength of the signal sent by all end users is the same. This means that they cannot send together at the same timeslot without destroying each other’s signal. All upstream traffic in this PON network is sent under the control of a software service called Dynamic Bandwidth Allocation (DBA). An upstream packet of a particular user cannot be sent without permission given by this DBA engine. This DBA SW engine has to grant and allocate each upstream packet that passes through this fiber based network. The DBA monitors the upstream traffic of each of the end users at the multi point side.  Based on this information the DBA will allocate some timeslots at each of the end users and it informs them about these allocations. These timeslots are unique and they are used by the end users to send the data present in their queues in to the network. The allocation of this timeslot must be updated each 125 microseconds.

One of the leading companies in the PON market is Nokia. Its broadband networks division has multiple development sites spread all over the world. One of these R&D sites is located in Antwerp, where the thesis and internship will take place.

You are/have:

Proficient in C++ Good knowledge of telecommunication principles, preferably for fiber technologies a bachelor's degree in engineering, preferrably on computer science.

Thesis Aim:

Currently this allocation done by the DBA engine takes into account the current traffic needs, the traffic profiles and the PON capacity. But is does not take into account the bandwidth consumption over time by each individual user. Telecom Operators are experiencing more and more issues in their networks due to super users, i.e., users that consume huge bandwidths over a longer period of time (e.g. continuous avg upstream data rate of 700 Mbps over 7 days). Having a mechanism in place at the operator side that alarms this to the operator and adjusts the traffic profiles for these super users to avoid PON network impact, would be valuable.

As a proof of concept we would like you to:

to analyse the problem, to search for a method to detect and monitor the super users in upstream and avoid PON network impact from super-user, to update the C++ code on our real-time embedded platform in one of our products.

Proposed Methodology:

Search for exiting literature related to this topic. (PON, DBA, traffic shaping, fairness) Study the existing code base. Devise a solution. Create code to implement this proposed solution. Prove on a test setup that the proposed solution works within the given constrains.