The agility and flexibility cloud provides are critical to helping customers meet their business needs, and most adopt a hybrid-cloud or multi-cloud approach. That said, cloud is not free, and the increase in cloud adoption has put more focus on the total cost of operations and how to lower it. After all, application infrastructure cost is one of the major components of IT expenses.

A prime example of how Citrix ADC helps many customers to reduce back-end infrastructure cost is through connection multiplexing. This blog post will highlight three ways Citrix ADC can help you save money on your cloud journey:

• Use of Citrix ADC instead of L4 load balancers that don’t support multiplexing on cloud
• Consolidation of L4 and L7 load balancing and application security in the same Citrix ADC for better management and visibility
• Complement cloud load balancers (for example, using Citrix ADC behind L4 cloud load balancers)

In each case Citrix ADC can reduce back-end infrastructure costs via connection multiplexing, resulting in the use of fewer servers.

What is Connection Multiplexing?

Connection multiplexing is a method of reusing connections to avoid the overhead on the server that comes with establishing new connections for each request. Connection multiplexing support in Citrix ADC ensures that server connections are efficiently reused, which results in dramatically reduced SSL/TLS load on back-end servers.

Solution 1: Use of Citrix ADC instead of L4 load balancers that don’t support multiplexing on cloud

For any given load, the use of Citrix ADC requires 40 percent fewer back-end servers when compared with L4 load balancers in the cloud. This is because Citrix ADC supports connection multiplexing. L4 cloud provider load balancers without multiplexing support must establish a new connection for each request, which places more compute burden on the back-end servers, especially for TCP and SSL/TLS.

For Example, a L4 load balancer without multiplexing support might require five back-end servers to cope with a load of 5,000 SSL connections per second. With Citrix ADC, three servers would suffice. Citrix ADC reuses connections, which reduces the processing overhead on each server by around 40 percent, as shown below.

Table 1: The difference in overall cost for compute resources to handle the given load on AWS Cloud

Table 2: The difference in overall cost for compute resources to handle the given load on Azure Cloud

The resulting savings here is $122 per month in AWS and $109.4 per month in Azure. In other scenarios, these saving can be much higher as customers use more servers to cope with larger workloads. In all the scenarios, you will see a cost savings of about 40 percent in server compute because of Citrix ADC and multiplexing support.

Solution 2: Consolidation of L4 and L7 load balancing and application security in the same Citrix ADC for better management and visibility

In many cloud deployments, customers use two different layers of load balancers for Layer 4 and Layer 7 decision making. The consolidation of distinct L4 and L7 load balancers into a single Citrix ADC provides three distinct advantages

• 40 percent savings on back-end infrastructure via multiplexing
• Lower operational overhead (consolidation of multiple service types — HTTPS, TLS/SSL-TCP, HTTP, TCP, UDP)
• Lower total cost of ownership — Citrix ADC supports both Layer 4 and Layer 7 Service types

Citrix ADC can consolidate multiple layers of load balancers to reduce costs.

In addition, the enhanced feature set of Citrix ADC reduces the need for additional services like a web application firewall for application security, reducing costs further.

Solution 3: Complement cloud load balancers (for example, using Citrix ADC behind L4 Cloud load balancers)

Some customers want to retain Cloud load balancers and use Citrix ADC, as shown below, to save on server workloads. There are a variety of reasons for this, including:

• Retain the L4 cloud load balancer as Tier-1 load balancer to maintain a single static IP address per availability zone
• Use Citrix ADC as a Tier-2 load balancer to reduce server cost by 40 percent
• Use Citrix ADC for its rich Layer 7 functionalities like global server load balancing (GSLB), rewrite, responder, authentication, and application security (WAF) use cases.

With Citrix ADC, you can lower server TCO by 40 percent, lower your operational overhead by consolidating multiple service types (HTTPS, TLS/SSL-TCP, HTTP, TCP, UDP) in a single Citrix ADC, and complement your Layer 4 cloud load balancer. Learn more about Citrix ADC today.