A computer-implemented method of compressing data between a source computer and a target computer to support continuous availability of applications (112,114,162,164), comprising: a) receiving a current instance of data in an input buffer, wherein the current instance of data logically defines a deduplication view that is a candidate portion of the data selected from the input buffer including at least one deduplication-view range (1522,1524)that is a selected portion of the deduplication view; b) selecting a candidate chunk of a representation of the deduplication view having a selected deduplication view range (1670, 1672); c) computing a signature hash from a signature length range of data starting in the candidate chunk; d) identifying a matching dictionary entry having a matching signature hash from a dictionary, wherein the matching dictionary entry prospectively identifies a location of a prior occurrence of a selected range of consecutive symbols including the signature length range of data within at least one of the representation of the current instance of data and a representation of a prior instance of data in the input buffer, wherein each dictionary entry is typed to enable persistence based upon at least one of the following: i) proximity to the current instance of data, ii) frequency of recurrence, and iii) length of time since initial matched occurrence; e) using the typed dictionary entry, partitioning the dictionary into multiple tiers enabling at least one of: i) varying bases for dictionary entry persistence within the dictionary, and ii) varying bases for match verification of the recurrence of the selected range; f) applying modes of compression selected from the group consisting of (i) repeat pattern replacement; (ii) deduplication mode (iii) deflate mode; and g) forming a deduplication processed representation of the selected deduplication view range, wherein a deduplication item is substituted for each selected range of consecutive symbols verified as recurring, wherein the deduplication item identifies the location of the prior occurrence of the selected range. a) receiving a current instance of data in an input buffer, wherein the current instance of data logically defines a deduplication view that is a candidate portion of the data selected from the input buffer including at least one deduplication-view range (1522,1524)that is a selected portion of the deduplication view; b) selecting a candidate chunk of a representation of the deduplication view having a selected deduplication view range (1670, 1672); c) computing a signature hash from a signature length range of data starting in the candidate chunk; d) identifying a matching dictionary entry having a matching signature hash from a dictionary, wherein the matching dictionary entry prospectively identifies a location of a prior occurrence of a selected range of consecutive symbols including the signature length range of data within at least one of the representation of the current instance of data and a representation of a prior instance of data in the input buffer, wherein each dictionary entry is typed to enable persistence based upon at least one of the following: i) proximity to the current instance of data, ii) frequency of recurrence, and iii) length of time since initial matched occurrence; e) using the typed dictionary entry, partitioning the dictionary into multiple tiers enabling at least one of: i) varying bases for dictionary entry persistence within the dictionary, and ii) varying bases for match verification of the recurrence of the selected range; f) applying modes of compression selected from the group consisting of (i) repeat pattern replacement; (ii) deduplication mode (iii) deflate mode; and g) forming a deduplication processed representation of the selected deduplication view range, wherein a deduplication item is substituted for each selected range of consecutive symbols verified as recurring, wherein the deduplication item identifies the location of the prior occurrence of the selected range.