---
title:  Common Topologies for HTTP Session Management
---

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Decide which topology is best for your usage. The module configuration process is slightly different for each topology.

By default, a peer-to-peer configuration creates a replicated region across all servers. By default, a client/server configuration creates a partitioned region across all servers.

## <a id="common_gemfire_topologies__p2p_configuration" class="no-quick-link"></a>Peer-to-Peer Configuration

<img src="../../images_svg/http_module_p2p_with_locator.svg" id="common_gemfire_topologies__image_nqv_gzw_rv" class="image" />

In a peer-to-peer configuration, each instance within an application server contains its own cache. Each instance communicates with the locator and with other instances as peers. By default, data is replicated. A peer-to-peer configuration is useful when multiple systems want fast access to all session data. This configuration is also the simplest one to set up and does not require any external processes.

## <a id="common_gemfire_topologies__cs_configuration" class="no-quick-link"></a>Client/Server Configuration

<img src="../../images_svg/http_module_cs_with_locator.svg" id="common_gemfire_topologies__image_oss_zyw_rv" class="image" />

In a client/server configuration, the Tomcat instance operates as a <%=vars.product_name%> client, which must communicate with one or more <%=vars.product_name%> servers to acquire session data. The client maintains its own local cache and will communicate with the server to satisfy cache misses. A client/server configuration is useful when you want to separate the application server instance from the cached session data. In this configuration, you can reduce the memory consumption of the application server since session data is stored in separate <%=vars.product_name%> server processes.
