The case studies in the Solutions Corner describe network design or deployment problems typically discussed during ExpertExpress sessions. They're based on real-life queries and consulting engagements but never represent an actual customer network.
- Large multi-homed content provider has experienced numerous brownouts in the Internet edge of its data center network caused by high CPU load on the Internet edge routers following a link or EBGP session loss.
- A large enterprise (the Customer) has an existing international WAN backbone using BGP as the routing protocol. They plan to replace a regional access network with DMVPN-based solution and want to extend the existing BGP routing protocol into the access network to be able to scale the access network to several thousand sites.
- In a network with two data centers connected with a layer-2 DCI link, implement optimal route advertisement toward enterprise WAN and Internet that survives failures of individual links, node, or subsystems, and avoids split-brain scenario or traffic blackholing.
- A large enterprise (the Customer) has a WAN backbone based on MPLS/VPN service offered by a regional Service Provider (SP). The traffic in the Customer’s WAN network has been increasing steadily prompting the customer to increase the MPLS/VPN bandwidth or to deploy an alternate VPN solution. The Customer decided to trial IPsec VPN over the public Internet, initially as a backup, and potentially as the primary WAN connectivity solution.
- In a network with two data centers (connected with a layer-3 DCI link), ensure the Internet users reach applications running in a data center even if all its Internet links fail.
- A large enterprise (the Customer) is building a private cloud infrastructure using leaf-and-spine fabric for internal network connectivity. The virtualization team hasn’t decided yet whether to use a commercial product (example: VMware vSphere) or an open-source alternative (KVM with OpenStack). It’s also unclear whether VLANs or overlay layer-2 segments will be used to implement virtual networks.