About policy settings for location awareness

You configure location awareness on the Location Awareness tab of the Manage > Services: Policies page. Location awareness enables Client Accelerator endpoints to detect that they are in a branch office with a SteelHead and to allow the branch office SteelHead to optimize their traffic.

When a Client Accelerator endpoint is in a branch office that has a SteelHead, the location awareness settings determine whether optimization is performed by the Client Accelerator endpoint or by the SteelHead. Client Accelerator endpoint can be configured to operate in any one of three modes when in the branch office:

• If latency-based location awareness is disabled (which also means that branch warming is unavailable), the Client Accelerator endpoint performs optimization. The Client Accelerator endpoint does not experience improved performance when accessing data segments that have been previously accessed by other users at the branch office, and the client warms only its own Client Accelerator RiOS data store. The branch office SteelHead does not warm its RiOS data store with data segments accessed by the Client Accelerator endpoint, so when another user at the branch office transfers the same data, the second user experiences cold performance.

• If latency-based location awareness is enabled but branch warming is not, then the branch office SteelHead performs optimization. In this case, the Client Accelerator endpoint experiences warm performance while in the branch office. The branch office SteelHead warms its RiOS data store with segments previously accessed by the Client Accelerator endpoint and by other users at the branch office. This is the default setting.

• If latency-based location awareness and branch warming are both enabled, the Client Accelerator endpoint will perform optimization with the server-side SteelHead, and it will also pull data segments from the branch-side SteelHead if another user in the branch has already accessed the same data. The Client Accelerator endpoint will also push all its newly acquired data segments to the branch SteelHead so other users may experience warm performance when they access that same data, whether the optimization is performed directly by the branch-side SteelHead or by another Client Accelerator endpoint that is in Branch Warming mode. When the user leaves the branch office, the Client Accelerator endpoint provides warm performance.

Branch warming co-operates with and optimizes transfers for a server-side SteelHead. New data transfers between the client and server are populated in the Client Accelerator RiOS data store, the branch SteelHead RiOS data store, and the server-side SteelHead RiOS data store.

When data is downloaded from the server, the server-side SteelHead checks if either the Client Accelerator endpoint or the branch SteelHead has the data in its RiOS data store. If either device already has the data segments, the server-side SteelHead sends only references to the data. The Client Accelerator endpoint and the branch SteelHead communicate with each other to resolve the references.

• Enable latency-based location awareness and branch warming on the controller.

• Enable branch warming on both the client-side and server-side SteelHeads.

• Both the client-side and server-side SteelHeads must be deployed in-path or virtual in-path (that is, no fixed-target rules).

• Enable enhanced autodiscovery on both the client-side and server-side SteelHeads.

Branch warming might not improve performance for configurations using Client Accelerator endpoints that communicate with multiple server-side appliances in different scenarios. For example, if a Client Accelerator home user peers with one server-side SteelHead after logging in through a VPN network and peers with a different server-side SteelHead after logging in from the branch office, branch warming does not improve performance.

For branch warming to work on the Client Accelerator endpoint, branch warming must be enabled on both the client-side and server-side SteelHeads. For your convenience, instructions are provided here for configuring the SteelHeads.

• Optimize over adapters specified above if latency to SteelHead is more than: ( ) ms—Specifies the value of latency to the SteelHead (in milliseconds) above which optimization over the specified adapters occurs. The default value is 10 ms.

• Enable branch warming—Enables branch warming. Branch warming is disabled by default.

• Adapters to optimize

– Position—Select start, end, or a rule number from the drop-down list. The controllers evaluate rules in numerical order, starting with rule 1. If the conditions set in the rule match, then the rule is applied, and the system moves on to the next packet. If the conditions set in the rule don’t match, the system consults the next rule. For example, if the conditions of rule 1 don’t match, rule 2 is consulted. If rule 2 matches the conditions, it is applied, and no further rules are consulted.

– Adapter—Determines the adapter. Select the adapter from the drop-down list. You can also add a new adapter when you add a new rule. Select Other Adapter(s) from the drop-down list and enter the adapter name in the Other - Please specify field.