Page 44 - 5G Basics - Core Network Aspects

1 Core network aspects

I.3 Caching

ICN supports two main caching mechanisms depending on how and where a data object is cached: on-path
caching and off-path caching.
On-path caching selects a caching point(s) among nodes on the downloading path when a data object is being
downloaded from its sender to requester. Since the caching decision can be made whenever data objects are
downloaded, on-path caching provides an implicit mechanism for ICN to distribute more data objects to the
places where there are heavy requests with the minimum extra overhead of caching protocol.
Off-path caching selects an optimal location of the network and caches a data object on the selected
locations. Its operation is the same as a traditional surrogate server placement in CDN in the sense that the
optimal selection of proper spots over the network yields optimal performance. However, off-path caching
may be suitable only for small networks since it becomes impractical for large networks due to the significant
increase in signalling traffic overhead caused by coordinated caching among caching nodes.

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