METHOD OF CACHING
Caching algorithms estimate the popularity (future request rate or re-use time) and base caching decision on popularity (future request rate or re-use time). Thereby the popularity (future request rate or re-use time) upon which the decisions are made, is not limited to the locally measured one, but a combination of all popularities of all storage means, where the weight of each is determined by social relations between users served by the different storage means.
1 . Method for storing a selection of multimedia objects by a first storage means, the method comprising:
serving a group of users by said first storage means;
calculating a first popularity factor for each of the multimedia objects based on a number of historical requests of the respective multimedia object by said group of users;
retrieving a database comprising information defining relations between said group of users and other groups of users served by respective further storage means;
retrieving a further popularity factor for each of the multimedia objects from each of said further storage means;
calculating a similarity factor defining a similarity between said first storage means and each one of said further storage means, based on the retrieved database;
calculating a second popularity factor for each of the multimedia objects based on said first popularity factor and said further popularity factors, wherein the weight of the further popularity factors depends on the corresponding calculated similarity factor;
selecting multimedia objects with the highest second popularity factor;
storing said selected multimedia objects in the first storage means.
2 . (canceled)
3 . Method according to claim 1 , wherein each of the further popularity factors are calculated based on a number of historical requests of the respective multimedia object by said respective other groups of users.
4 . Method according to claim 1 , wherein said database comprises a matrix wherein at least one of a column and a row represent said users, and wherein at least another one of said column and said row represent said further users, and wherein the values in the matrix define the relation between the respective users identified by the row index and the users identified by the column index.
5 . Method according to claim 4 , wherein said matrix comprises a first predetermined value when a user identified by the row index is linked to the another user identified by the column index via a social community, and a second predetermined value when the user identified by the row index is not linked to the other user identified by the column index via said social community.
6 . Method according to claim 5 , wherein the social community comprises at least one of Facebook, Twitter, Instagram, Google+, Netflix, Snapshot, Pinterest and Vine.
7 . Method according to claim 1 , wherein the selecting multimedia objects comprises ranking the multimedia objects from highest to lowest second popularity factor and selecting a top list of the ranked multimedia objects.
8 . Method according to claim 7 , wherein the top list comprises a predetermined number of multimedia objects, or comprises a number of multimedia objects occupying a predetermined data capacity.
9 . Method according to claim 1 wherein said retrieving said database comprises observing requests made by said number of users and by said further number of users over a period of time, and detecting respective similarities between said number of users and said further number of users.
10 . Method according to claim 1 , wherein said calculating said second popularity factor is calculated for each multimedia object as the sum of the first popularity factor and the further popularity factors multiplied by their corresponding similarity factors.
11 . Method according to claim 11 , wherein the second popularity factor further includes an externally determined popularity factor received from an external server, multiplied by a predetermined factor.
12 . Storage means adapted for serving a number of users in a network, and wherein said storage means comprises programmed instructions for executing the method according to claim 1 .
13 . Router comprising a storage means according to claim 12 .
14 . Computer program adapted for being executed by a computer to execute the method according to claim 1 .
15 . Computer readable storage medium comprising programmed instructions to execute the method according to claim 1 .