Software Defined Networking: Last against the wall … · Software Defined Networking: Last against...
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Software Defined Networking: Last against the wall Steve Cosgrove Whitireia New Zealand [email protected] ABSTRACT The combination of Ethernet and TCP/IP dominates current networking. The routers used to support that network paradigm can be traced to the founding of Cisco Systems in the 1980s. In the 1990s, Cisco purchased Ethernet switching technology, and grew to dominate the infrastructure of the Internet, and enterprise networking. During the first decade of the 21st century researchers looked at various incantations of a ‘soft switch’ for use in Ethernet networks. Stanford University was one of the leaders in this research. By 2009, the Openflow protocol had been developed there, and we saw signs of the vendor co-operation that has developed to the current SDN environment (Greene, 2009). Now SDN products are available for production use from a large number of vendors, in addition to companies and educational institutes who are contributing software to the project. This poster outlines the concepts behind SDN and suggests guidelines for when to introduce the topic to an academic programme. It describes an approach used to introduce SDN to level six networking students. Keywords Big Data, SDN, Software Defined Network, Ethernet, Openflow, Network Function Virtualisation, Virtualization 1. WHAT? – WHY SDN IS SPECIAL SDN switches only hold rules, learned from the controller, which they use to decide what to do with each frame received. An SDN controller holds policy which represents business and technical rules for network traffic This contrasts with legacy networking, where each network device (typically a router or switch) contains all rules, and information it needs to make decisions. There are various protocols and tools available to automate the process, but in the end, legacy networks end up being a large number of autonomous devices. 2. WHY? – AN INTRODUCTION TO SDN The networking environment is changing. The growth of SDN is described here, and it is put in a context of other aspects of the modern ICT environment. As research and industry driven applied organisations, Polytechnics and Institutes of Technology need to introduce students to SDN. 3. The Opening of Everything In the first few decades of computing, resources were scarce and tightly controlled. The creation of the C programming language and Unix operating system started making software development more accessible. The release of the IBM PC introduced standard hardware, and an operating system that ran on multiple vendors’ hardware. The community development of Linux in the 1990s drove open adoption of TCP/IP networking protocols. In the 21 st century, virtualisation of hardware became common. Then followed standardised virtual storage protocols. Likewise, since it was first a published concept (Metcalfe, & Boggs, 1976), Ethernet networking slowly gained popularity. By the late 1990s, Ethernet networking became ubiquitous. The Hitchhiker's Guide to the Galaxy referred to those who were to be “… first against the wall when the revolution comes," (Adams, 1980). This author suggests proprietary and closed ICT systems are a hindrance to the progress of IT. It follows, the networking infrastructure was the ‘Last against the wall’ of the revolution toward open, programmable, ICT systems. SDN provides the infrastructure and tools necessary for networks that can be modified dynamically to meet the needs of clients, in the way hardware, operating systems, and software has been made accessible over the past 35 years or so. 4. PROGRESS OF THE REVOLUTION Google implemented software defined networking (SDN) in its data centres around the world (Feamster, Rexford, & Zegura, 2013). The unrelenting growth in SDN research, and uptake by all significant network hardware manufacturers (Feamster et al. 2013), has led to widespread adoption of SDN in corporate datacentres, and uptake in specialised, mission critical roles, such as movement of scientific big data (Cotter, 2014). 4.1 A Prediction of the Future In the evolution of Information and Communication Technology (ICT), technical considerations tend to take a second priority to financial considerations when selecting business software. The first benefit of SDN, suggested by business authors, is potential for cost savings. Indications of the speed of the widespread This poster appeared at the 6 th annual conference of Computing and Information Technology Research and Education New Zealand (CITRENZ2015) and the 28 h Annual Conference of the National Advisory Committee on Computing Qualifications, Queenstown, New Zealand, October 6-9, 2015. Michael Verhaart, Amit Sarkar, Rosemarie Tomlinson and Emre Erturk (Eds).
Transcript of Software Defined Networking: Last against the wall … · Software Defined Networking: Last against...
Software Defined Networking: Last against the wall Steve Cosgrove
Whitireia New Zealand
ABSTRACT The combination of Ethernet and TCP/IP dominates current networking. The routers used to support that network paradigm can be traced to the founding of Cisco Systems in the 1980s. In the 1990s, Cisco purchased Ethernet switching technology, and grew to dominate the infrastructure of the Internet, and enterprise networking.
During the first decade of the 21st century researchers looked at various incantations of a ‘soft switch’ for use in Ethernet networks. Stanford University was one of the leaders in this research. By 2009, the Openflow protocol had been developed there, and we saw signs of the vendor co-operation that has developed to the current SDN environment (Greene, 2009). Now SDN products are available for production use from a large number of vendors, in addition to companies and educational institutes who are contributing software to the project.
This poster outlines the concepts behind SDN and suggests guidelines for when to introduce the topic to an academic programme. It describes an approach used to introduce SDN to level six networking students.
Keywords
Big Data, SDN, Software Defined Network, Ethernet, Openflow, Network Function Virtualisation, Virtualization
1. WHAT? – WHY SDN IS SPECIAL SDN switches only hold rules, learned from the controller, which they use to decide what to do with each frame received. An SDN controller holds policy which represents business and technical rules for network traffic
This contrasts with legacy networking, where each network device (typically a router or switch) contains all rules, and information it needs to make decisions.
There are various protocols and tools available to automate the process, but in the end, legacy networks end up being a large number of autonomous devices.
2. WHY? – AN INTRODUCTION TO SDN The networking environment is changing. The growth of SDN is described here, and it is put in a context of other aspects of the modern ICT environment.
As research and industry driven applied organisations, Polytechnics and Institutes of Technology need to introduce students to SDN.
3. The Opening of Everything In the first few decades of computing, resources were scarce and tightly controlled. The creation of the C programming language and Unix operating system started making software development more accessible.
The release of the IBM PC introduced standard hardware, and an operating system that ran on multiple vendors’ hardware. The community development of Linux in the 1990s drove open adoption of TCP/IP networking protocols.
In the 21st century, virtualisation of hardware became common. Then followed standardised virtual storage protocols.
Likewise, since it was first a published concept (Metcalfe, & Boggs, 1976), Ethernet networking slowly gained popularity. By the late 1990s, Ethernet networking became ubiquitous.
The Hitchhiker's Guide to the Galaxy referred to those who were to be “… first against the wall when the revolution comes," (Adams, 1980). This author suggests proprietary and closed ICT systems are a hindrance to the progress of IT. It follows, the networking infrastructure was the ‘Last against the wall’ of the revolution toward open, programmable, ICT systems.
SDN provides the infrastructure and tools necessary for networks that can be modified dynamically to meet the needs of clients, in the way hardware, operating systems, and software has been made accessible over the past 35 years or so.
4. PROGRESS OF THE REVOLUTION Google implemented software defined networking (SDN) in its data centres around the world (Feamster, Rexford, & Zegura, 2013). The unrelenting growth in SDN research, and uptake by all significant network hardware manufacturers (Feamster et al. 2013), has led to widespread adoption of SDN in corporate datacentres, and uptake in specialised, mission critical roles, such as movement of scientific big data (Cotter, 2014).
4.1 A Prediction of the Future In the evolution of Information and Communication Technology (ICT), technical considerations tend to take a second priority to financial considerations when selecting business software. The first benefit of SDN, suggested by business authors, is potential for cost savings. Indications of the speed of the widespread
This poster appeared at the 6th annual conference of Computing and Information Technology Research and Education New Zealand (CITRENZ2015) and the 28h Annual Conference of the National Advisory Committee on Computing Qualifications, Queenstown, New Zealand, October 6-9, 2015. Michael Verhaart, Amit Sarkar, Rosemarie Tomlinson and Emre Erturk (Eds).
adoption of SDN is shown in datacentres, and the leading vendors who are contributing to hardware and software to production and research projects (https://www.opendaylight.org/membership). The OpenDaylight project is creating a reference framework to ease a widespread move to SDN technologies. (OpenDaylight, nd).
5. WHEN? – GOOD THINGS TAKE TIME This section introduces some of the moves towards getting SDN beyond the datacentre, and into academic curricula.
5.1 Widespread use One of the broadest applications of SDN would be the Royal Melbourne Institute of Technology (RMIT) (Pearce, 2014). At another end of the ‘food chain’, Yiakoumis, Yap, Katti, Parulkar, and McKeown (2011) describe one example of the use of SDN to provide advanced functionality to home network users.
5.2 Available Resources Resource preparation is a significant consideration for academics considering course changes.
A key tool for researching SDN is Mininet, which Lantz, Heller, McKeown (2010) described as a prototyping environment that supports SDN research by using lightweight virtualization. Mininet creates virtual hardware (H1 and H2 in Figure 1). By default, it will also create:
Virtual switches (standard Linux OpenVswitch) A virtual SDN controller ‘Physical’ links between all devices. These links use
real Linux sockets between the virtual devices, however, link quality can be ‘degraded’ by specifying a particular speed, or packet loss etc.
The switches and controller can be replaced with different software, or physical devices.
The Mininet Team provide a guide to downloading and learning to use the product here: http://mininet.org/download/
5.3 Academic imperative Consideration must be given to the wider academic environment. If a suitable course needs to be revised, or there is space in a programme for a new course, then that could be a good time!
6. HOW? – AN INTRODUCTION EXAMPLE Mininet provides a very flexible, and low cost path to SDN.
A casual scan of the literature suggests that penetration is concentrated on software and postgraduate research. This section outlines initial integration of SDN content into a level six (‘2nd year’) networking course.
6.1 20 + SDN = 30 The process of changing Whitireia IT courses from 20 credits to 15 presented an option to create a 30 credit networking course to replace the existing 20 credit one. The new course covers routing and switching from Cisco Network Academy program. The remaining content applies the general routing and switching information already learned, to a SDN environment.
6.2 SDN Hardware Content Using blades on the Whitireia supercomputer (Chard S, Cosgrove S 2011), each student was allocated a virtual machine on which they could run Mininet, along with controllers such as Ryu and OpenDaylight. Exercises were based on example tutorials used at the 2014 NZNOG conference (2014 https://nsrc.org/workshops/2014/nznog-sdn/wiki ) and from SDN Hub. http://sdnhub.org/tutorials/opendaylight/
6.3 The Future is Software The next step is to incorporate some SDN hardware into the School of IT teaching and research network. This will be used to build the skills of staff, and provide a platform for post-graduate research projects.
There is also the vision to find space in our programmes to include development of software to control the SDN environment.
7. REFERENCES Adams, D. (1980). The Hitchhiker's Guide To The Galaxy. New
York: Harmony Books.
Chard S, & Cosgrove S. (2011). Is it a paper weight, light dimmer, patio heater, or a high performance computing centre? eResearch Symposium, 2011. Dunedin Otago, NZ
Cotter, S. (2014) SDN-based innovation in New Zealand, Science and Technology Conference (Modern Networking Technologies) (MoNeTeC), 2014 International , vol., no., pp.1,2, 28-29 Oct. 2014.
Feamster N, Rexford J, & Zegura E. (2013). The Road to SDN: An Intellectual History of Programmable Networks. Georgia Tech Princeton University, GA. https://www.cs.princeton.edu/courses/archive/fall13/cos597E/papers/sdnhistory.pdf.
Greene K. (2009) TR10: Software-defined networking. MIT Technology Review, March/April 2009. http://www2.technologyreview.com/article/412194/tr10-software-defined-networking/
Lantz B, Heller B, & McKeown N. (2010). A Network in a Laptop: Rapid Prototyping for Software-Defined Networks. 9th ACM Workshop on Hot Topics in Networks, 2010, Monterey, CA.
Metcalfe R, & Boggs D. (1976). Ethernet: distributed packet switching for local computer networks. Commun. ACM 19, 7 (July 1976), 395-404. DOI=10.1145/360248.360253
OpenDaylight.(nd). About the Foundation retrieved from https://www.opendaylight.org/about-foundation
Pearce R,(2014). RMIT University builds virtual networking labs for students. Computerworld. Retrieved from http://www.computerworld.com.au/article/560653/rmit-university-builds-virtual-networking-labs-students/
Yiakoumis Y, Yap K, Katti S, Parulkar G, & McKeown N. (2011). Slicing home networks. In Proceedings of the 2nd ACM SIGCOMM workshop on Home networks (HomeNets '11). ACM, New York, NY, USA, 1-6.
Figure 1 Basic Mininet topology, based on https://wiki.opendaylight.org/view/OVSDB_Integration:Mininet_OVSDB_Tutorial.
