This Industry Viewpoint was contributed by Rob Shore, Senior Vice President of Marketing, Infinera
While IT organizations, new business models, and the customer experience tend to dominate the digital transformation headlines, the communications infrastructure underlying digital transformation is quietly but surely undergoing a paradigm shift. This shift includes a rethinking of the role of traditional network technologies and elements, including IP routers – a bedrock of the internet backbone.
IP routing will continue to play a key role as networks evolve. But market forces are driving a fresh look at IP transport network architectures. The emergence of 5G, for example, promises a major increase in bandwidth to users and capacity per unit area, while also enabling new applications based on ultra- low latency and high availability, and massive IoT scale.
Breaking Down Barriers to Innovation
New emerging network concepts and applications - as in 5G networks - require fast technology innovation cycles. Yet traditional monolithic network element architectures restrict the flexibility for changes and increase the cost and complexity of the network. This is especially the case of traditional IP routers based on closed, proprietary hardware, with dependencies on chassis-based architectures required for scaling that result in vendor lock-in and lead to snail-pRoaced innovation and high costs. To accelerate innovation and prepare the network for new applications, the disaggregation of hardware and software components delivers the promise of easily adding and upgrading best-in-breed functions.
Disaggregation is not a new concept. In fact, in the economic literature it is a natural consequence of industry maturity and has been successful adopted in a wide range of industries in addition to IT and telecoms. One recent carrier network example is the disaggregation of optical transport systems into Open Line Systems (OLS) and open transponders/muxponders. Another is the disaggregation of network functions such as firewalls, broadband network gateways and the mobile core into software-based virtual network functions (VNFs) running on server hardware powered by commodity general purpose CPUs. The network edge is also being disaggregated based on data center principles, with initiatives such as the ONF’s Central Office Re-Architected as a Data Center (CORD) and ETSI’s Multi-Access Edge Compute (MEC).
The Open Network Revolution
Routers however have until now, by and large resisted the open networking trend, with disaggregation a major threat to the business models and profitability of the leading router vendors. However, as the router industry has matured, merchant silicon and open source software have made router disaggregation possible. High performance silicon is available from a number of merchant vendors and is already widely used by leading router vendors in many of their traditional router product lines. Cost-effective pluggables can be used for high-speed interconnects based on 100GbE and 400GbE, providing an alternative to chassis backplanes. Open Network Linux (ONL) provides a powerful platform for Network Operating Systems (NOS) enabling developers to leverage a library of basic open source functions focusing on more advance functions and differentiation, while Open Network Install Environment (ONIE) provides an open environment for installing a compliant NOS onto third party white box hardware.
|High Performance silicon including network processors and fabric chips available from merchant silicon vendors|
|High-Speed Ethernet Pluggables||100GE and 400GbE. Optical and Direct Attached Copper (DAC) cable assemblies. Cost-effective alternative to chassis backplanes.|
|Open Network Linux (ONL)||Provides a platform for NOS development leveraging a library of basic router functions.|
|Open Network Install Environment (ONIE)||An open source initiative that defines an open “install environment” for white box switches.|
Table 1 - Router Disaggregation Enablers
Traditional routers provide a monolithic package of hardware and software from a single vendor. While this model has in the past provided benefits with guaranteed hardware/software interoperability and a single point of contact for purchasing, service and support, it today creates a number of challenges for network operators. The high vendor lock-in of proprietary, closed routers and the small number of router vendors results in limited pricing pressure and high costs. Innovation is dependent on the capabilities of the single selected vendor rather than an ecosystem and prevents network operators from leveraging different rates of hardware and software innovation independently, or selecting best-of breed hardware and software independently.
Principles of Router Disaggregation
At its most basic level disaggregated routing separates the router software and hardware. The hardware becomes a white box based on merchant silicon, while the software becomes a Network Operators System (NOS). And while the white box and NOS can now come from different vendors, you cannot just take any white box and run any NOS on it. Software is needed to adapt the NOS to the specific white box and its merchant silicon. This software comprises two elements. Software that comes on the white box to load the NOS, with ONIE, as discussed previously, becoming a de facto standard. And a hardware abstraction layer in the NOS that adapts it to run on the specific merchant silicon in the white box.
Unlocking the Benefits
Enabled by reduced vendor lock-in, disaggregated routing provides benefits to network operators building the next-generation infrastructure to support digital transformation. These benefits include competitive pricing, more choice, faster innovation and cost-effective scaling, all of which ultimately have the potential to significantly lower both CapEx and OpEx, as shown in table 2.
|Lower CapEx||Lower OpEx|
|✓ Competitive Pricing at Selection
✓ Competitive Upgrade Pricing
|✓ Competitive Service &
|More Choice||✓ Mix and Match Best Hardware and Best Software
= More Optimal Price/Performance
|✓ Reduced Cost Per Bit
✓ More Efficient Routing
|✓ Lower Footprint
✓ Lower Power Consumption
|Cost-effective Scaling||✓ Reduced Upfront CapEx
✓ Extended Solution Lifespan
✓ Simplified Sparing
|✓ Optimized Space & Power
✓ Fewer Part Numbers
✓ Simplified Sparing
Table 2- Disaggregated Routing Lower CapEx and OpEx
Reduced Vendor Lock-In
Traditional monolithic routers force operators to purchase a bundle of hardware and software from a single vendor, then lock them in for the duration of the router lifecycle in the network. With a small number of vendors dominating the service provider router market, competitive pricing pressures are muted. By lowering the barriers to entry for both hardware and software vendors, disaggregation has the potential to significantly increase price competition. Reduced vendor-lock-in is also a key enabler for more choice and faster innovation.
Disaggregated routing enables network operators to optimally mix and match the best hardware and the best software for a given use case. Not all white boxes are the same. Interfaces, capacity, buffering, latency, features and functionality will differ from white box to white box. Carrier-class white boxes may also need to address requirements like synchronization, redundancy, environmental hardening, sub 300mm depth, and stacking interfaces. Likewise, not all NOS are the same. Different use cases will require different features and protocols. A carrier-class NOS will also require a degree of protocol “hardening” that may not be required for an enterprise-class NOS, as well as high availability features such as hitless software upgrades and multi-unit scaling. However, with at least fifteen vendors currently providing multiple white boxes and with at least ten current options for the NOS, disaggregated routing provides an unprecedented level of choice with the flexibility to mix and match white boxes and NOS to best match the requirements of a particular operator/use case.
Faster Innovation Cycles
Innovation is key to driving down CapEx and OpEx, scaling performance and enabling new services. With a traditional monolithic router, innovation is constrained by the capabilities of the single selected vendor. The disaggregated router approach enables network operators to leverage the innovation capabilities of the entire ecosystem, selecting best-in-class vendors and upgrading based on the innovation cycle of each component of the disaggregated solution. As discussed previously, with reduced barriers to entry, new and smaller vendors will now be able to compete, bringing their innovation capabilities to the market.
Disaggregated routing avoids having to choose between a fully utilized device that meets the initial requirements but will not scale to meet future requirements and an under-utilized chassis with high upfront CapEx, footprint and power consumption. Starting with a single white box, capacity can be first scaled by adding additional white boxes leveraging stacking, then as capacity requirements grow fabric white boxes can be added. With this approach, disaggregated routing can also address the capacity requirements of different parts of the network, all leveraging a very limited set of individual white boxes and a common NOS.
In markets around the world 5G is driving transport network upgrades that will mark a milestone in digital transformation. IP routing will have a key role to play due to its scalability, flexible resiliency and the operational simplicity of a single end-to-end control plane. Providing an alternative to traditional monolithic architectures, however, disaggregated routing enables network operators to gain the traditional benefits of IP routing while also benefiting from minimized vendor lock-in, competitive pricing, more choice, faster innovation and cost-effective scaling, all with the potential to significantly lower both CapEx and OpEx.