Implementation and Evaluation of a Network Element Control Protocol

Tämä opinnäytetyö koostuu erään ohjaus- ja välityselementtien väliseen tiedonsiirtoon käytettävän verkkoelementin ohjausprotokollan toteutuksesta ja arvioinnista. Tätä ohjausprotokollaa käytetään verkkoelementin sisällä verkko-operaattorin runkoverkossa. Kirjoittaja on tutkinut kolmea yleisesti käytössä olevaa dynaamista verkkokytkimen ohjausprotokollaa ja yksi näistä on valittu toteutettavaksi tässä tutkimuksessa. Tämä kyseinen protokolla on forwarding and control element separation (ForCES). Euroopan Unionin seitsemännen puiteohjelman ETNA-projektissa on tehty IETF:n määrittelystä poikkeavia muutoksia ForCES-protokollaan: PATH-DATATLV- kerros poistettiin sekä muita TLV-tietorakenteita muutettiin projektin tarpeiden mukaisesti. ETNA on myös lisännyt ylimääräisiä ID-arvoja, tietotyyppejä, tapahtuma- ja tuloskoodeja sekä muita arvoja. Arvot on valittu niin, etteivät ne mene päällekkäin IETF:n ForCES määrittelyjen kanssa. Tässä tutkimuksessa tehty ohjelmistototeutus on C++-kirjasto, jossa on 31 luokkaa ja 15 436 riviä lähdekoodia. Ohjelmistokoodi on testattu kirjoittajan tekemällä testiohjelmalla ja se toimii ilman tunnettuja virhetoimintoja. Tutkimuksen arviointiosuus koostuu muistinvarauksen ja viestin muodostusajan mittaamisesta. Kilotavun mittaiset ja 185 TLV-tietorakennetta sisältävät testiviestit varasivat yli 500 % ylimääräistä muistia verrattuna viesten nettopituuteen. Tämän ylimääräisen muistinkäytön suhteellinen osuus viestien nettopituuteen verrattuna kuitenkin pienenee, samalla kun TLV-tietorakenteiden pituus kasvaa. Viestinmuodostuksen käsittelyaika kasvoi lineaarisesti, mutta mittauksissa havaittiin viestien käsittelyn alussa jonkin verran ylimääräistä käsittelyaikaa etenkin lyhyillä viesteillä, joissa oli vähän TLV-tietorakenteita. Suunnittelimme ja toteutimme Aalto-yliopistossa ohjauselementin ForCES-protokollan toteutuksen ja Ben Gurionin yliopisto Israelissa oli vastuussa välityselementin suunnittelusta ja toteutuksesta. Molemmat toteutukset yhdistettiin ja demonstroitiin yhdessä kehitettyä uutta runkoverkon mallia.This thesis consists of the implementation and evaluation of a network element control protocol that is used for the communication between the control element and the forwarding element in a network element in a network operator's core network. The author has investigated three commonly used dynamic switch control protocols and one of them is chosen to be implemented in this study. This protocol is the forwarding and control element separation (ForCES). In the EU 7th framework program's ETNA project, there has been done some modifications to the IETF specified ForCES protocol: the PATH-DATA-TLV layer was removed among other type-length-value (TLV) data structure modifications. ETNA has also added extra IDs, data types, event and result codes, and other values choosing them so that they do not overlap with the values in the IETF ForCES specification. The implementation done in this study is a C++ library with 31 classes and 15 436 lines of source code. The code was tested with a test program written by the author and is working without any known bugs. The evaluation part of the study consists of memory allocation and message construction time performance measurements. The test messages with one kilobyte length and 185 TLVs allocated over 500 % extra memory compared to the message network length. However, this overhead is proportional to the network length of the message and will decrease as the length of the TLVs increase. The processing time for the message construction was linearly increasing, but there was some offset time at the beginning of the message processing especially with short messages with a few TLVs. In Aalto University, we designed and implemented the control element implementation of the ForCES protocol and the Ben Gurion University was responsible for the design and implementation of the forwarding element. Both implementations were integrated together and there was demonstrated a new co-developed proof-of-concept core network model

A Survey on the Contributions of Software-Defined Networking to Traffic Engineering

Since the appearance of OpenFlow back in 2008, software-defined networking (SDN) has gained momentum. Although there are some discrepancies between the standards developing organizations working with SDN about what SDN is and how it is defined, they all outline traffic engineering (TE) as a key application. One of the most common objectives of TE is the congestion minimization, where techniques such as traffic splitting among multiple paths or advanced reservation systems are used. In such a scenario, this manuscript surveys the role of a comprehensive list of SDN protocols in TE solutions, in order to assess how these protocols can benefit TE. The SDN protocols have been categorized using the SDN architecture proposed by the open networking foundation, which differentiates among data-controller plane interfaces, application-controller plane interfaces, and management interfaces, in order to state how the interface type in which they operate influences TE. In addition, the impact of the SDN protocols on TE has been evaluated by comparing them with the path computation element (PCE)-based architecture. The PCE-based architecture has been selected to measure the impact of SDN on TE because it is the most novel TE architecture until the date, and because it already defines a set of metrics to measure the performance of TE solutions. We conclude that using the three types of interfaces simultaneously will result in more powerful and enhanced TE solutions, since they benefit TE in complementary ways.European Commission through the Horizon 2020 Research and Innovation Programme (GN4) under Grant 691567 Spanish Ministry of Economy and Competitiveness under the Secure Deployment of Services Over SDN and NFV-based Networks Project S&NSEC under Grant TEC2013-47960-C4-3-

SDN Access Control for the Masses

The evolution of Software-Defined Networking (SDN) has so far been predominantly geared towards defining and refining the abstractions on the forwarding and control planes. However, despite a maturing south-bound interface and a range of proposed network operating systems, the network management application layer is yet to be specified and standardized. It has currently poorly defined access control mechanisms that could be exposed to network applications. Available mechanisms allow only rudimentary control and lack procedures to partition resource access across multiple dimensions. We address this by extending the SDN north-bound interface to provide control over shared resources to key stakeholders of network infrastructure: network providers, operators and application developers. We introduce a taxonomy of SDN access models, describe a comprehensive design for SDN access control and implement the proposed solution as an extension of the ONOS network controller intent framework

Will SDN be part of 5G?

For many, this is no longer a valid question and the case is considered settled with SDN/NFV (Software Defined Networking/Network Function Virtualization) providing the inevitable innovation enablers solving many outstanding management issues regarding 5G. However, given the monumental task of softwarization of radio access network (RAN) while 5G is just around the corner and some companies have started unveiling their 5G equipment already, the concern is very realistic that we may only see some point solutions involving SDN technology instead of a fully SDN-enabled RAN. This survey paper identifies all important obstacles in the way and looks at the state of the art of the relevant solutions. This survey is different from the previous surveys on SDN-based RAN as it focuses on the salient problems and discusses solutions proposed within and outside SDN literature. Our main focus is on fronthaul, backward compatibility, supposedly disruptive nature of SDN deployment, business cases and monetization of SDN related upgrades, latency of general purpose processors (GPP), and additional security vulnerabilities, softwarization brings along to the RAN. We have also provided a summary of the architectural developments in SDN-based RAN landscape as not all work can be covered under the focused issues. This paper provides a comprehensive survey on the state of the art of SDN-based RAN and clearly points out the gaps in the technology.Comment: 33 pages, 10 figure

Packet forwarding for heterogeneous technologies for integrated fronthaul/backhaul

Proceeding of: 2016 European Conference on Networks and Communications (EuCNC)To meet the future mobile user demand at a reduced cost, operators are looking at solutions such as C-RAN and different functional splits to decrease the cost of deploying and maintaining cell sites. The use of these technologies forces operators to manage two physically separated networks, one for backhaul and one for fronthaul. To solve this issue, transport networks for 5G will carry both fronthaul and backhaul traffic operating over heterogeneous data plane technologies. Such an integrated fronthaul/backhaul (denoted as 5G-Crosshaul) transport network will be software-controlled to adapt to the fluctuating capacity demand of the new generation air interfaces. Based on a proposed data- and control-plane architecture for 5G-Crosshaul, we propose a frame format common to both fronthaul and backhaul traffic as well as a corresponding abstraction of the forwarding behavior of the network elements. The common frame format and the forwarding abstraction define the information to be exchanged at the southbound interface (SBI) of the 5G-Crosshaul Control Infrastructure (XCI). This paper derives requirements for the SBI from 5G use cases.The authors of this paper have been sponsored in part by the project H2020-ICT-2014-2 “5G-Crosshaul”: The 5G integrated fronthaul/backhaul” (671598

Building Programmable Wireless Networks: An Architectural Survey

In recent times, there have been a lot of efforts for improving the ossified Internet architecture in a bid to sustain unstinted growth and innovation. A major reason for the perceived architectural ossification is the lack of ability to program the network as a system. This situation has resulted partly from historical decisions in the original Internet design which emphasized decentralized network operations through co-located data and control planes on each network device. The situation for wireless networks is no different resulting in a lot of complexity and a plethora of largely incompatible wireless technologies. The emergence of "programmable wireless networks", that allow greater flexibility, ease of management and configurability, is a step in the right direction to overcome the aforementioned shortcomings of the wireless networks. In this paper, we provide a broad overview of the architectures proposed in literature for building programmable wireless networks focusing primarily on three popular techniques, i.e., software defined networks, cognitive radio networks, and virtualized networks. This survey is a self-contained tutorial on these techniques and its applications. We also discuss the opportunities and challenges in building next-generation programmable wireless networks and identify open research issues and future research directions.Comment: 19 page