Memory Cost Analysis for OpenFlow Multiple Table Lookup

Multiple Table Lookup architectures in Software Defined Networking (SDN) open the door for exciting new network applications. The development of the OpenFlow protocol supported the SDN paradigm. However, the first version of the OpenFlow protocol specified a single table lookup model with the associated constraints in flow entry numbers and search capabilities. With the introduction of multiple table lookup in OpenFlow v1.1, flexible and efficient search to support SDN application innovation became possible. However, implementation of multiple table lookup in hardware to meet high performance requirements is non-trivial. One possible approach involves the use of multi-dimensional lookup algorithms. A high lookup performance can be achieved by using embedded memory for flow entry storage. A detailed study of OpenFlow flow filters for multi-dimensional lookup is presented in this paper. Based on a proposed multiple table lookup architecture, the memory consumption and update performance using parallel single field searches are evaluated. The results demonstrate an efficient multi-table lookup implementation with minimum memory usage.

Violence and Commemoration in the New Northern Ireland: Space, Memory and Management

On June 27th 2012, the Deputy First Minister of Northern Ireland and former IRA commander, Martin McGuinness shook hands with Queen Elizabeth II for the first time at an event in Belfast. For many the gesture symbolised the consolidation of Northern Ireland's transition to peace, the meeting of cultures and traditions, and hope for the future. Only a few weeks later however violence spilled onto the streets of north and west Belfast following a series of commemorative parades, marking a summer of hostilities. Those hostilities spread into a winter of protest, riot and discontent around flags and emblems and a year of tensions and commemorative-related violence marked again by a summer of rioting and protest in 2013. Outwardly these examples present two very different pictures of the 'new' Northern Ireland; the former of a society moving forward and putting the past behind it and the latter apparently divided over and wedded to different constructions of the past. Furthermore they revealed two very different 'places', the public handshake in the arena of public space; the rioting and fighting occurring in spaces distanced from the public sphere. This paper has also illustrated the difficulties around the ‘public management’ of conflict and transition as many within public agencies struggle with duties to uphold good relations and promote good governance within an environment of political strife, hostility and continuing violence.

This paper presents the key findings and implications of an exploratory project funded by the Arts and Humanities Research Council, explored the phenomenon of commemorative-related violence in Northern Ireland. We focus on 1) why the performance or celebration of the past can sometimes lead to violence in specific places; 2) map and analyse the levels of commemorative related violence in the past 15 years and 3) look at the public management implications of both conflict and transition at a strategic level within the public sector.

Historical Dialogue and Memory in Organisational Transition: the case of the Police in Northern Ireland

During Northern Ireland’s transition towards peace the role of the police as an actor in the conflict has been a key point of contention. As such, the reform of policing has been central to conflict transformation. Within this process, the role of dialogue about what policing had been and could be in the future has been vital. Such institutional post violence change processes have been hugely significant in illustrating both organisational resistance to change and the need for transitions to be powerfully manoeuvred through complex, political, organisational and cultural processes (Buchanan and Badham 1999; Pettigrew 2012). The radical and reforming nature of policing transition (Murphy 2013) has been both organisationally challenging (requiring significant transformational leadership, resourcing and external engagement from wider civic society) and politically unusual. Indeed, in a society emerging from violence the NI police are the only public sector organisation to have engaged structurally and culturally in understanding the point at which their core roles intersected with the ‘management’ of the conflict in NI generally. This paper presents an analysis of the role of historical dialogue in organisational change process, using the RUC / PSNI case. It proposes that historical dialogue is not just an external, societal process but also an internal organisational process and as such, has implications for managing institutional change in societies emerging from conflict. In doing so, it builds theoretical links between literature on conflict transformation and that on organisational memory and empirically explores messaging internal to the RUC before and during the four main periods of organisational change (Murphy 2013), with dialogue aimed at an external audience. It offers an analysis of how historical dialogue itself impacts on and is impacted by the organisational realities of change itself.