The lifetime given to SA cache entries when created or refreshed. This is the [SG-State-Period] in the MSDP spec. A value of 0 means no SA caching is done by this MSDP speaker. This object does not measure time per se; instead, it is the delta from the time at which an SA message is received at which it should be expired if not refreshed. (i.e., it is the value of fsMsdpSACacheExpiryTime immediately after receiving an SA message applying to that row.) As such, TimeInterval would be a more appropriate SYNTAX; it remains TimeTicks for backwards compatibility.