Jayshree Ullal

Author Archives: Jayshree Ullal

Transforming Silos into Universal Cloud Networking

We have witnessed a massive shift in the way applications are built and deployed, moving away from siloed IT to seamless workloads, workflows and work-streams. This revolution has changed the fundamental way that networks are architected to enable support of cloud native applications. With these new architectures, one can now automate and provision the entire network with real time agility, ushering in a new class of cloud networks.

The Universal Spine Is Born!

The rapid migration from enterprise to cloud, driven by the economics of scale, the convergence of local and wide-area networking (LAN-WAN), the migration from Fibre Channel to IP storage, the rise of analytics and the emergence of new cloud applications is dramatic. In the past two years, we have witnessed a massive shift in the way applications are built and deployed, moving away from legacy siloed infrastructure to seamless workload mobility. The demands of these new workloads change the way spine networks are reconstructed for cloud networking. As physical compute or storage silos evolve to support cloud applications, one can automate and provision the entire network to handle any workload, workflow or workstream, with real time agility.

Connecting Clouds with Spine Internetworking

As more and more modern applications move to hybrid or public clouds, the placement of these applications strains network infrastructure. It only makes sense to leverage the massive investments of public cloud providers. The need for public clouds to interact directly with data center resources requires the distributed deployment of cloud applications and appropriate networking...
Continue reading »

Security in Cloud Networking

Enterprises are grappling with security in their infrastructure and many point products try to solve this in different use -cases. As enterprises migrate from north-south to east-west traffic patterns, the need for consistent security across cloud-network and firewall infrastructure is paramount. Furthermore, additional security concerns emerge as organizations contemplate leveraging access to the public cloud...
Continue reading »

Mainstream Cloud Networking with Flexible Ethernet

Networking vendors have long touted distinct routers and switches with different LAN and WAN interfaces. Remember IBM Token Ring versus Ethernet? Or ATM or Sonet versus Ethernet or more recently Fibre Channel SANs versus Ethernet? Ethernet truly addresses the present state and next generation of networking, usually obsoleting the alternatives. Ethernet has proven its evolution...
Continue reading »

The Game Changer in Cloud Networking

The networking market is at an exciting pivot point, evolving away from legacy enterprise networking to the cloud. While the public cloud providers (“titans”) may take a “do it yourself” approach to engineering cloud network designs, mainstream enterprises demand a “cloudified” turnkey solution and want to emulate cloud operators. The increasingly massive scale of address tables, devices, flooding, broadcast traffic from discovery protocols, subnets and routing protocols have accelerated the need for disruption in networking workflows, making Arista a unique and welcome pioneer for customers ready to make SDN a reality.

Software Driven Cloud Networking Trends

To appreciate the need for SDN and cloud solutions one must step back and understand why the cloud network is dramatically different from legacy networking.

First, in a cloud, everything is dynamic. Resources become available and go off-line, users are logging in and out, and workloads are going up or down depending on compute needs. This is a fundamental difference of cloud versus static computing in enterprises.

Second, cloud data centers are much larger than typical enterprise datacenters and can contain tens, even hundreds of thousands of servers. Legacy management practices and policies that are used in smaller datacenters don’t apply to clouds since Continue reading

Converged Cloud-Class Networking – The Next Frontier

Scale-out cloud-applications continue to be the most disruptive force to traditional network architectures in the data center. They demand an open and uncompromised cloud network, unshackled by monolithic and the prehistoric proprietary networks.

Our customers and partners are reshaping this traditional networking industry. Previously burdened by monolithic software and underperforming hardware, the new evolving bifurcation of computing architectures for modern cloud-based applications has resulted in key trends and drivers for this evolution including:

1. Unstructured data is everywhere. Whether from users, applications or machines, it is growing exponentially with no vertical or industry being spared. One current obstacle to working with large data sets is the use of relational databases and desktop statistics/visualization packages that require massively parallel software running on hundreds, or even thousands of servers.
2. New workloads are changing the notion of separate SANs. This impacts the role of networking and IP storage, where virtual machine mobility sustains multiple gigabits of throughput by default with multicore processors.
3. Cloud intensive applications such as content distribution, and new infrastructure technologies such as containers and Hadoop clusters are pushing the envelope of what is possible with massively parallel transactions. These new large-scale data analytics have given birth to converged Continue reading

Software Stack Choices in Cloud Networking

The networking industry is changing rapidly with demand for more dynamic control of big data, and scale-out cloud applications. The inevitable shift to software-defined workloads and workflows is crystal clear. This calls for more “disaggregation” of software models for the network stack.

Should networking move to a more open standards-based approach or continue with legacy stacks? The answer is defined by considering the following three options for networking software stacks, and the actual choice depends on the factors as shown below in Figure 1.

1. Classic OS: The established network vendors tend to develop multi-million lines of complex software code with enterprise or service provider class features for LAN or WAN. This closed monolithic “Blob-OS” model can be based on modified and proprietary versions of a BSD or Linux Kernel. Traditional enterprise support is the hallmark of this model, but innovation is rarely evident. Claims of programmability usually include band-aid APIs, or guest virtual machine access. The classic OS addresses mature markets akin to a mainframe usually for customers with siloed IT stacks that support legacy applications.

2. Cloud OS: At Arista, our software engineers build based on an open Linux Kernel, providing programmable capabilities that legacy switch-based Blob-OSs do Continue reading

Relevance of SDN in Cloud Networking

SDN (Software Defined Networking) is finally becoming clearer. It is not “Still Don’t Know” nor is it a specific overlay controller. Simply put, it is an open and programmable way to build networks for customers looking at utilizing hybrid combinations of public and private cloud access.

We are witnessing a shift from multi-tier oversubscribed legacy enterprise networks to two-tier leaf-spine or single-tier Spline™ cloud networks with east- west traffic patterns scaling across thousands of servers. Arista was the first to introduce this new architectural “leaf-spine” approach for cloud-based networks and five years later others are still attempting to mimic. Lets review some practical examples.

Facebook: Take an important and familiar social networking application, Facebook. Their public information shows that they deploy a memcache architecture, which allowed them to reduce the user access time to half a millisecond by using fewer network tiers, resulting in lower application latency. As we log into Facebook, the single login request triggers thousands of look-ups on databases and memcache servers. Legacy enterprise multi-tiered networks would result in delayed look-ups and would negatively impact the user experience and interest in a significant way.

Amazon: Shopping couldn’t be easier than online on your favorite site. Have you Continue reading

Software-Defined Cloud Networking Reflections

Every year I reflect upon how my predictions compare to actual outcomes. Once again, that time has come, so let’s take a walk together down 2014’s memory lane, while also looking forward to exciting industry developments in 2015. Clearly innovation in networking is returning as we are seeing venture capitalists once again investing in networking innovation!

Prediction #1: The rise in server virtualization is driving network virtualization deployments.

Evaluation #1: Half True.

One can transcend network boundaries at both L2 and L3, building seamless virtual and physical networks with VXLAN as the key L2 over L3 foundation. The VXLAN specification co-authored by Arista and VMware, and in a similar vein the NVGRE specification co-authored by Arista and Microsoft, were key turning points for network virtualization. Arista’s strategic partnership announced in August 2014 with VMware (NSX, vSphere and vCloud Director) and multivendor interoperability with other controllers from Nuage Networks, OpenStack and the OpenFlow community were key milestones in 2014. New protocols take time to be adopted – usually 3-5 years. VXLAN is at that tipping point for broader implementations in place of the proprietary, vendor-specific options we have seen.

Prediction #2: “SDN” is no more “Still Don’t Know”.

Evaluation #2: Continue reading

Pioneers vs. Protectors in Cloud Networking Innovation

The innovation of hundreds of startup companies created the Internet, and the Internet has changed the world. Innovation continues to have a dramatic impact on networking in recent years. These new developments have changed the way applications, workloads and networks interact. Having been involved in this industry for more than three decades, I have witnessed and been part of these transformations from the 1980s to the 2015 era. Each phase of innovation has been characterized by new companies and entrants, as depicted below:

PHASES OF NETWORK INNOVATION
Epoch Vendors Network Technologies Trends
First
1980–1995
AT&T, Sun, 3Com, NET, Proteon,
UB, BBN, DEC, IBM
ARPANET, Circuits, Hubs,
SNA, Ethernet, Token
Ring, Routers
Terminal-Mainframes and
Minis, Channel Attach
Second
1995–2010
Cisco, Juniper, Nortel/Bay,
Alcatel, Lucent, Avaya
Switching, Multiprotocol
Routing, LAN-WAN,
TCP/IP
PC, Client-Server, Web,
North-South traffic
Third
2010–present
Arista, VMware, Facebook, Microsoft,
Splunk, Red Hat, Palo Alto, Aruba,
many others
The SDN Era of Open,
Programmable
Networking,
DevOps meets NetOps,
Universal Cloud Networks
Mobile Virtual Workloads
and Workflows,
Big Data,
Hyperscale Web,
Virtual Machines /
Containers

Traits of a Pioneering Innovator vs. Protector

Dominant companies often fall by the wayside when they do not anticipate and react to clear market trends as Continue reading

Happy Tenth Anniversary Arista Networks!

Every year at Arista has been filled with milestones and enriching memories. I want to acknowledge and thank each and every Arista well-wisher for contributing to this incredible experience. So let’s take a walk together down memory lane and look back on our journey from start-up to a now public company. I think of Arista’s first decade as being comprised of three phases:

2004+ Our Humble Beginnings:

Funded in a unique fashion, without traditional venture capital investment, Arista (first called Arastra, located on Arastradero road in Palo Alto) was placed in a unique position. Our founders, Andy and David, were our funders, too, and they cared deeply about building the company with the right technology foundation. Ken Duda, also a founder and our EOS software genius, brought a radical, resilient and programmable network-OS for modern, disruptive applications. Bringing some of the best and brightest engineering minds together resulted in an innovative network-wide operating system that challenged legacy enterprise switching vendors. Andy Bechtolsheim and I launched the company officially in October 2008. With just 50 engineers we gained 50 customers by the end of 2008, proving what small focused teams could accomplish. Our early adopters welcomed us as a breath of Continue reading

The Evolution from Products to Platforms in Software Driven Cloud Networking

Legacy networking vendors have often declared that they do not build “boxes” but actually build “systems and architectures”. I have tried to understand what that really means. Undoubtedly, new applications on the Internet have evolved and now depend on a modern infrastructure that outlives any particular static workload or physical machine. Indeed, at Arista, we along with our customers are looking at a technology evolution that goes beyond individual components to a universal cloud architecture.

Disruptive Innovation Begins with Products, aka “Boxes”

Building a “best of breed” product is a vital foundation to building a good system. Typical metrics may include feeds and speeds such as latency, power, port density (non-blocking), fabric capacity, throughput and scale combined with a feature-rich network operating system. Examples of this include Cisco’s routers and Catalyst switches (with IOS) in the 1990s, F5’s Big IP and Splunk’s data analytics in the past decade, or even more recently, Arista’s 7000 series Leaf-Spine-Spline products. Vendors with breakthrough products are pioneers and thought-leaders in their markets and often establish trends rather than follow them. Sustained differentiation beyond point features is a common theme. Such products are disruptive in nature, bringing critical business benefits and reducing capex spend within Continue reading

Balanced Buffer Design for Mission-Critical Cloud Networks

Leading customers and researchers in cloud and data center networking have been promoting the importance of understanding the impact of TCP/IP flow and congestion control, speed mismatch and adequate buffering for many decades. The problem space has not changed during this time, but the increase in the rates of speed by 100X and in storage capacity by 1000X have aggravated the problem of reliable performance under load for data intensive content and for storage applications, in particular. One Arista fan summed it up best by saying:

“Basically the numbers have changed by order of magnitude, but the problem is the same!”

Poor performance and inadequate buffering in a demanding network is a painful reminder that buffering, flow control, and congestion management must be properly designed. TCP/IP was not inherently built for rate-fairness, and packets are intentionally dropped (yes, only window fairness is possible). Yet the effect of these drops can be multiplicative given major speed mismatches of 10-100X inside the data center. In the past, QoS and rate metering were adequate. However, at multi-gigabit and terabit speeds and particularly as more storage moves from Fiber Channel (with buffer credits) to Ethernet, packet loss gets more acute.

Benefits of Balanced Continue reading

The Impact of White Box on Cloud Networking

The adoption of cloud networking architectures by both the hyper-scale cloud companies and increasingly enterprise networks proves the need for open standards and modern networking software to gain the benefits of agility, programmability and resiliency. These architectures are all driven by the move to standardized topologies and container-scale deployment to achieve cloud economics.

The recent Facebook introduction of a reference design to align to the OCP (Open Compute Platform) server project with a network switch (“Wedge”) based on a Linux OS is a good benchmark for the use of open standards, control and merchant silicon. While many may view this as a threat to legacy proprietary networking, to me it’s a welcome validation of Arista’s approach to building modern software that is open and programmable as opposed to a proprietary, bloated and complex legacy OS. It is also a symbol of Arista’s co-development of APIs offering access for specific application control in Facebook’s network. This is a fitting example of how “white box” technology could be applied to a specific SDN use case. It is not trying to address broad data center use with multiple applications and mobile workloads.

Arista EOS for Universal Workloads and Workflows

Two factors are driving Continue reading