Despite differences, the advantages of a software based network edge are compelling and there is emerging consensus behind this architecture with a large number of solutions available, including: Hadoop, Mesos, OpenStack, VMware NSX, Juniper OpenContrail, Midokura Midonet, Nuage Networks Virtual Services Platform, CPLANE Dynamic Virtual Networks and PLUMgrid Open Networking Suite.
In addition, the move to a software based network edge is leading to the adoption of configuration management and deployment tools from the DevOps community such as Puppet, Chef, Ansible, CFEngine, and Salt. As network switches become more open, these same tools are increasingly being used to manage switch configurations, reducing operational complexity and increasing agility by coordinating network, server, and application configurations.
The following articles from network virtualization proponents touch on the need for visibility and performance from the physical core:
- Demo: End to end, hop by hop, physical and virtual network flow visibility with NSX, Brad Hedlund
- A Tale of Two Layers – Correlating Overlay and Physical Network Data for better OpenStack Network Analytics, OpenContrail Blog
- Elephant Detection in the vSwitch With Performance Handling in the Underlay, Network Heresy
In this evolving environment, how does software defined networking apply to the physical core and deliver the visibility and control needed to support the emerging software edge?
|Credit: Cisco ACI|
The recent announcement of Switch Fabric Accelerator (SFA) offers a modular alternative to Cisco ACI. The controller leverages open APIs to monitor and control network devices, and works with existing edge controllers and configuration management tools to deliver the visibility and control of physical network resources needed to support current and emerging edge services.
The following table compares the two approaches:
|Cisco ACI||InMon SFA|
|Switch vendors||Cisco only - Nexus 9K||Inexpensive commodity switches from multiple vendors, including: Alcatel-Lucent Enterprise, Arista, Brocade, Cisco Nexus 3K, Cumulus, Dell, Edge-Core, Extreme, Huawei, IBM, HP, Juniper, Mellanox, NEC, Pica8, Pluribus, Quanta, ZTE|
|Switch hardware||Custom Application Leaf Engine (ALE) chip + merchant silicon ASIC||Merchant silicon ASICs from Broadcom, Intel or Marvell|
|Software vSwitch||Cisco Application Virtual Switch managed by Cisco APIC||Agnostic. Choose vSwitch to maximize functionality of edge. vSwitch is managed by edge controller.|
|Visibility||Analytics based on industry standard sFlow measurement|
|Boost throughput||Cisco proprietary ALE chip and proprietary VxLAN extension||Controls based on industry standard sFlow measurement and hybrid control API|
|Reduce latency||Cisco proprietary ALE chip and proprietary VxLAN extension||Controls based on DSCP/QoS, industry standard measurement and hybrid control API|
|Limit impact of DDoS attacks||Controls based on industry standard sFlow measurements and hybrid control API|