IT and networking departments are evolving new strategies and technologies to address demand for apps, bandwidth and services.
Users today take the network for granted. But behind the scenes, IT and networking departments are working feverishly to evolve new strategies and deploy technologies that can satisfy the appetite for more apps, bandwidth and services – cheaper and faster.
To accommodate an application-centric perspective, the concerted shift to software-defined networking (SDN) entails realigning the network architecture conceptually into three distinct layers that are accessible through open application programming interfaces (APIs).
First, there is the infrastructure layer, which consists of the network elements and devices that provide packet switching and forwarding.
The second layer is the control layer, which centralises control functionality and supervises the network forwarding behaviour through an open interface.
The third layer is the application layer, where the business applications are accessed via the SDN communications services.
The SDN architecture has three key attributes: logically centralised intelligence; programmability; and abstraction, where the business applications on the SDN are abstracted from the underlying network technologies.
Cloud computing realignment
Embracing the hybrid cloud entails more than just scaled-up server virtualisation. The key to performance improvements and cost reduction involves consolidation and virtualisation, along with changes in management and governance, risk and compliance procedures.
Consolidation entails reducing the number of datacentres and physical servers. It means integrating multiple IT components, such as servers, networking and storage. By combining these components into a single virtual entity, IT can pool and share its collective resources. By centralising the management of those resources, significant cost savings can be achieved.
Recent announcements from legacy IT suppliers, such as SAP, Oracle, Microsoft and Cisco, demonstrate their support for the hybrid cloud. While building out their own clouds, they are also offering most of their software on public clouds, notably Amazon Web Services.
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A new direction
The shift to alternative networks in the local area network (LAN) affects the whole Open Systems Interconnection (OSI) model, from the network layer to the application layer. The traditional OSI layers can be software controlled on bare metal servers. The wide area network (WAN) connection going through a virtual Layer 2 switch filters and forwards traffic only at the data link layer using switches such as Juniper’s MX or HP’s 2920 series.
The next step is a Virtual Layer 3-4 router for Layer 3 routing, typically by partitioning sets of ports into separate virtual LANs and routing between them. The newer series of virtual router products from Cisco, Juniper and other networks can add load balancers, network firewalls, application firewalls, SSL VPN, IPSec VPN, intrusion prevention, content switching, compression and caching. It is not just servers that are being virtualised. Applications, hardware resources and everything in between can reside in virtual containers to reduce costs and increase flexibility. Providers, such as Embrane and Brocade, focus on creating agile networks through the virtualisation of Layer 3-7 network services.
Application performance in highly scalable clusters may require front-end intelligence. This highlights the importance of application-delivery controllers (ADCs). These can also provide compression, caching, connection multiplexing, traffic shaping, application layer security, SSL offload and content switching, distributed denial of service (DDoS) protection, advanced routing strategies and server performance monitoring. The focus on applications has redefined the corporate IT service delivery and implementation cycle (DevOps). This encompasses processes from development through quality assessment to staging and operations. This means network planners can build a more intelligent test environment, add more automation into the network and enable a private cloud offering.
DevOps also encompasses processes designed to facilitate the collaboration between app development and IT operations, to bring the portfolio of IT technology and applications forward. To get decision makers involved, IT planners want to combine the business process framework with application and information frameworks. This has led corporate IT to adopt tools, such as Oracle AIA and IBM Maximo, to facilitate integration.
Commercial network virtualisation
To realise their own performance and cost requirements, telcos and infrastructure providers are implementing network function virtualisation (NFV) to address:
- The increasing variety of proprietary hardware appliances;
- The complexity of integrating and deploying these appliances in a network;
- The still shorter hardware lifecycles as innovation accelerates.
This is achieved by evolving standard IT virtualisation technology to consolidate multiple network equipment types onto industry-standard high-volume servers, switches and storage. Network functions are implemented in software that can run on a range of industry-standard bare-metal server hardware, which can be instantiated in various locations in the network as required. This technology promises significant benefits for network operators and their customers by virtualising and consolidating network functions that traditionally have been implemented in dedicated hardware. NFV is thus highly complementary to SDN, being mutually beneficial but not dependent on each other.
By using cloud technologies, network operators expect to achieve greater agility and accelerate new service deployments while driving down operating expense and capital expenditure costs. Over-the-top-services, such as Facebook; e-commerce suppliers such as Amazon; and telcos such as BT and Verizon, are all going down this path. This threatens the proprietary business models of companies such as Citrix, Microsoft, F5 Networks, Red Hat, Sourcefire, Canonical, Embrane, Juniper, Brocade, Arista Networks, Big Switch Networks, Extreme Networks and NoviFlow.
However, it is good news for the dominant X86 server manufacturers, notably HP, Dell and Lenovo. Dell is using specialised compute pods to provide acceleration for SDN to facilitate NFV, such as a high-density Z9500 switch. It also has an OpenStack fabric controller to simplify NFV deployments. With its active infrastructure, Dell offers IT services with a workload-optimised, automated and integrated infrastructure, unified management (Active Systems Manager) and pre-integrated solutions (Active Systems).
Networking equipment suppliers have responded with their own hardware platforms, notably Cisco, by launching a series of software and platform releases that emphasise new degrees of openness (for example, OpFlex to replace Open Flow). These network hardware providers are able to offer not only their own underlying hardware, but also their own global intercloud network infrastructure. After the SDN-NFV consolidation of high-cost dedicated single-purpose hardware appliances, service providers see the creation of software as a service (SaaS) SDN-NFV clouds emerging in 2015-16, leading to virtual service providers offering seamless capacity and scalability by 2020.
Market and technology indicators point in the same direction: consolidation, convergence and virtualisation with SDN in a hybrid cloud environment – in the WAN and the LAN. Network performance will improve with lower operating expenditure. But right now standards are still fluid, and suppliers are jockeying for positions, creating dead ends and lock-ins to first-generation, end-to-end systems.
Migrating systems and apps to virtual servers in the cloud or between cloud providers is still tricky, requiring snapshotting data/apps from the old server and reloading them to the new server while restarting the apps. To minimise cost and downtime, extra tools, such as Vision Solutions Double-Take Move, are often needed. Decision-makers must weigh investing now (and expect to pay a premium) to get the performance, against waiting, but factor in capital expenditure investments in migration tools and more mature software platforms in a few years when the technology passes the hype phase and stabilises more. Now is the right time to establish the integrated business-IT DevOps organisation to lead the development and implementation process with a phased SDN-cloud migration, adapted to the existing asset depreciation cycle.