When covering options based on Software defined and Open Networking during engagements, I make use or a particular slide (which is fluid and always evolving) – which discusses the Design Principles for Future Ready DC Networks. The preamble and build up focuses on the all too familiar themes of SDN/ON value and benefits, What problems they are a Solution to, to what end are they a means.
I compile notes for the key themes around SDN/ON so I have a ready recourse should I need. The source of the notes could be Analyst reports, Forums, Foundations, and my own thoughts. This list is not exhaustive by any means, and I may tweak it with additions or deletions based on what is relevant to the particular customer, e.g. orchestration or micro-services/containers.
I will contribute to the blog, some of the themes and trends which are deemed to be the key.
The De-coupling of the components making up the (Previously) vertically integrated box. This separation has many benefits e.g. innovation, scale and changes to each layer, independently of the others.
- The choice of OS is no longer tied to the box.
“Interest and adoption of white-/brite-box switching has increased significantly within hyperscale data centers … expect it to reach 22% of the total DC Ethernet switch market by 2020 (Gartner 2017)
- The control plane and data plane no longer co-exist in the box.
SDN is “The physical separation of the network control plane from the forwarding plane, and where a control plane controls several devices.” ONF, https://www.opennetworking.org/sdn-definition/
- The box is merchant silicon based commodity switch (No specialized ASICs).
“The NGDCNs found at some of the world’s most advanced data centers (LinkedIn, FaceBook, Google, Microsoft) are driving towards modular pod approaches …. utilizing cheaper commodity switches based off switching merchant-silicon from providers like Broadcom, Marvell ..” (SDxCentral, Next Gen DCN 2017)
“ …Given the broad spectrum of software options, we believe that merchant-based platforms can meet the needs of at least 80% of enterprises.” (Gartner 2017)
- Cisco Nexus 3k/9K (2nd Gen):
- ASE, LSE = Cisco (Custom) ASIC [16 nm]
- NFE = Merchant Silicon: Broadcom Tomahawk/Trident 2+ [28-40 nm]
Garnet MQ for the DCN further notes that while some vendors are still focused on custom ASICs, atleast for certain usecases where developing the entire vertical stack would put them at advantage, there is a general industry-wide move where the focus of the innovation is increasingly on the software, while silicon is reduced to being commoditized/merchant.
Dell EMC’s next generation OS for the data center – OS10, makes use of a Switch Abstraction interface that abstracts the NPU, and makes it possible to program it. The OS runs an unmodified version of Linux (based on Debian Jesse), which facilitates both standardisation, as well as making innovation independent of any proprietary code base.
While the number of ways in which Dis-aggregation has an impact would be a list without end, some of the things to consider include:
- Operational Cost Savings
Reduced management overhead and time to launch a service or set up a network – including automation. Network management functions can be executed via a software on the virtual level, reducing the time and cost of managing physical hardware changes and configurations.
- Capital Cost Savings
COTS hardware and increased interoperability of networking gear, is reducing the number of proprietary networking products and pushing the networking industry toward greater standardization. Over time, this allows merchant silicon vendors to create high quality, lower cost products which contribute to lower hardware costs overall. (SDxCentral, 2017)