PCoIP client-side image caching stores image content on the client to avoid retransmission. This feature reduces bandwidth usage.
The PCoIP image cache captures spatial, as well as temporal, redundancy. For example, when you scroll down through a PDF document, new content appears from the bottom of the window and the oldest content disappears from the top of the window. All the other content remains constant and moves upward. The PCoIP image cache is capable of detecting this spatial and temporal redundancy.
Because during scrolling, the display information sent to the client device is primarily a sequence of cache indices, using the image cache saves a significant amount of bandwidth. This efficient scrolling has benefits both on the LAN and over the WAN.
On the LAN, where bandwidth is relatively unconstrained, using client-side image caching delivers significant bandwidth savings.
Over the WAN, to stay within the available bandwidth constraints, scrolling performance would be degraded without client-side caching. Over the WAN, client-side caching saves bandwidth and ensure a smooth, highly responsive scrolling experience.
With client-side caching, the client stores portions of the display that were previously transmitted. The cache size is one-half of the available RAM. If that amount of RAM is less than 50MB, the cache size is 50MB.