Cisco CSS 11500 Series content services switches (Figure 4) and the Cisco Content Switching Module (CSM) for Cisco Catalyst? 6500 Series switches (Figure 5) offer an integrated GSLB solution. These server load balancers contain DNS processing capabilities, allowing a network designer to deploy a GSLB solution without the addition of any external devices to process DNS requests. These Cisco products are targeted at disaster recovery and global load balancing of a small number of data centers.
In switch-based GSLB deployments, the Cisco CSM and the Cisco CSS 11500 Series are simultaneously performing two major processes. The first process is interacting with the DNS infrastructure, as described previously, and the second process is load-balancing client traffic across multiple servers. These products are unique in that they combine local server load balancing with global server load balancing.
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