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ITD: Load Balancing, Traffic Steering & Clustering using Nexus 5k/6k/7k/9k

Cisco Intelligent Traffic Director (ITD) is an innovative solution to bridge the performance gap between a multi-terabit switch and gigabit servers and appliances. It is a hardware based multi-terabit layer 4 load-balancing, traffic steering and clustering solution on the Nexus 5k/6k/7k/9k series of switches.

It allows customers to deploy servers and appliances from any vendor with no network or topology changes. With a few simple configuration steps on a Cisco Nexus switch, customers can create an appliance or server cluster and deploy multiple devices to scale service capacity with ease. The servers or appliances do not have to be directly connected to the Cisco Nexus switch.

ITD won the Best of Interop 2015 in Data Center Category.

With our patent pending innovative algorithms, ITD (Intelligent Traffic Director) supports IP-stickiness, resiliency, consistent hash, exclude access-list, NAT (EFT), VIP, health monitoring, sophisticated failure handling policies, N+M redundancy, IPv4, IPv6, VRF, weighted load-balancing, bi-directional flow-coherency, and IPSLA probes including DNS. There is no service module or external appliance needed. ITD provides order of magnitude CAPEX and OPEX savings for the customers. ITD is much superior than legacy solutions like PBR, WCCP, ECMP, port-channel, layer-4 load-balancer appliances.

ITD provides :

  1. Hardware based multi-terabit/s L3/L4 load-balancing at wire-speed.
  2. Zero latency load-balancing.
  3. CAPEX savings : No service module or external L3/L4 load-balancer needed. Every Nexus port can be used as load-balancer.
  4. Redirect line-rate traffic to any devices, for example web cache engines, Web Accelerator Engines (WAE), video-caches, etc.
  5. Capability to create clusters of devices, for example, Firewalls, Intrusion Prevention System (IPS), or Web Application Firewall (WAF), Hadoop cluster
  6. IP-stickiness
  7. Resilient (like resilient ECMP), Consistent hash
  8. VIP based L4 load-balancing
  9. NAT (available for EFT/PoC). Allows non-DSR deployments.
  10. Weighted load-balancing
  11. Load-balances to large number of devices/servers
  12. ACL along with redirection and load balancing simultaneously.
  13. Bi-directional flow-coherency. Traffic from A–>B and B–>A goes to same node.
  14. Order of magnitude OPEX savings : reduction in configuration, and ease of deployment
  15. Order of magnitude CAPEX savings : Wiring, Power, Rackspace and Cost savings
  16. The servers/appliances don’t have to be directly connected to Nexus switch
  17. Monitoring the health of servers/appliances.
  18. N + M redundancy.
  19. Automatic failure handling of servers/appliances.
  20. VRF support, vPC support, VDC support
  21. Supported on all linecards of Nexus 9k/7k/6k/5k series.
  22. Supports both IPv4 and IPv6
  23. Cisco Prime DCNM Support
  24. exclude access-list
  25. No certification, integration, or qualification needed between the devices and the Cisco NX-OS switch.
  26. The feature does not add any load to the supervisor CPU.
  27. ITD uses orders of magnitude less hardware TCAM resources than WCCP.
  28. Handles unlimited number of flows.

For example,

  • Load-balance traffic to 256 servers of 10Gbps each.
  • Load-balance to cluster of Firewalls. ITD is much superior than PBR.
  • Scale IPS, IDS and WAF by load-balancing to standalone devices.
  • Scale the NFV solution by load-balancing to low cost VM/container based NFV.
  • Scale the WAAS / WAE solution.
  • Scale the VDS-TC (video-caching) solution.
  • Scale the Layer-7 load-balancer, by distributing traffic to L7 LBs.
  • ECMP/Port-channel cause re-hashing of flows. ITD is resilient, and doesn’t cause re-hashing on node add/delete/failure.

Documentation, slides, videos:

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Please note that ITD is not a replacement for Layer-7 load-balancer (URL, cookies, SSL, etc). Please email: for further questions.

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