Choosing On-Box or Off-Box for Deployment of a GoldenGate Replicat Process

When you deploy GoldenGate for TimesTen, you ultimately instantiate a set of processes that are responsible for receiving all replicated data from the GoldenGate source, storing it in a (local) trail file, reading the replicated data from the trail file and applying it to the target TimesTen database.

On-Box	Off-Box
If you deploy GoldenGate for TimesTen in the same host, VM, container, or pod as the target TimesTen database, then you can use either direct mode or client-server connectivity. This is known as an on-box deployment in GoldenGate terms. Generally, direct mode connectivity is preferred and recommended for this scenario	If you deploy GoldenGate for TimesTen in a different host, VM, container, or pod to the target TimesTen database, then you have to use client-server connectivity. In GoldenGate terms this is an off-box deployment.
TimesTen direct mode is a local only connectivity method that enables applications to interact with a local (same host) TimesTen database.	TimesTen client-server mode provides regular client-server connectivity through TCP/IP connections.
Direct mode connections use a highly efficient mechanism that eliminates inter-process communication, context switches and other overheads. Direct mode delivers the lowest possible data access latency together with high throughput. Use of direct mode is limited to application processes that are executing in one of the following environments: In the same bare metal host as the TimesTen database. In the same virtual machine as the TimesTen database. In the same container as the TimesTen database or, for Kubernetes environments, in a container in the same pod as the TimesTen database container.	In client-server mode, the applications can run anywhere that has suitable network connectivity to the host where TimesTen is running.
Direct mode connections offer better performance with less overhead. Using direct mode connections will significantly increase the complexity if you want high availability when using a combination of TimesTen and GoldenGate configurations. For example, when you combine GoldenGate with either a TimesTen active-standby pair or TimesTen Scaleout, automated failover and recovery for GoldenGate is significantly more complex compared to an off-box configuration using client-server connections. Host resources (CPU, memory, storage) must be sufficient to accommodate the TimesTen database instance, the TimesTen database, all GoldenGate processes, all associated processing plus any other local processing (such as applications).	Client-server mode potentially offers more flexibility than direct mode, but this flexibility comes at the cost of increased overhead and lower performance due to network latency, additional processing, and so on.