Abstract:
A system and method are provided for associating and storing data in contiguous memory locations of a secondary memory to enable efficient searching of the archived data. Current events are organized in a main memory within a data structure, e.g., an R-tree, chosen to increase the likelihood that data clustered together are more likely to relate to a same query. Most recent data is temporarily stored in the main memory to ensure that most additions of new data occur initially into the main memory, thereby enabling very high rates of data addition. The incidence of successive reads of data from a same disk memory block is increased and the length of time spent in seeking data on the disk is thereby reduced. Segments may be selected for serialization and transfer to the secondary memory without regard to age range of the data or minimal size of the block when main memory is approaching overload.

Description:
FIELD OF THE INVENTION  
       [0001]     The Present Invention relates to the organization and storage of information in electronic records by means of information technology systems. More particularly, the Present Invention relates to systems and techniques of data storage and access using data tree structures.  
       BACKGROUND OF THE INVENTION  
       [0002]     The method of organization of information stored within an electronic archive can greatly effect the average speed with which sought for information can be located within, and retrieved from, the electronic archive. In particular, most prior art optical and magnetic data storage disk devices organize data-records into individuated blocks of data and record each individuated block into a separate and physically contiguous sequence of memory locations. The average seek time required to locate a block storing a sought-for data-record stored on a data storage disk might be on the order of 10 milliseconds, while the average additional time required to locate a second sought-for data-record stored internally within the same block might be on the order of 100 microseconds. In contrast, the average search time required to find two data-records located on two different contiguous blocks of this exemplar data storage disk would typically be at least as large as two average block seek times of 10 milliseconds and might therefore be on the order of 20 milliseconds (i.e., two block seek times of 10 milliseconds each), while the average search time required to find two data-records stored within the same contiguous block would be on the order of 10.1 milliseconds (i.e., one average block seek time of 10 milliseconds to locate the first data-record and an average internal seek time of 100 microseconds to locate the second data-record).  
         [0003]     The average time required to search for information stored on a data storage disk can therefore by decreased when the method of grouping the data-records into individuated blocks increases the likelihood of occurrence that all the information required to satisfy a search of the archived data is stored in data-records stored within the fewer contiguous blocks of sequential memory locations of the disk. In other words, data structures that that reduce the average number of block seeks per query tend to be more time efficient.  
         [0004]     In certain prior art data archiving techniques, certain data-records are formatted to contain an information received from an electronic message, as well as a plurality of dimensional parameters. The index values of each the dimensional parameters may be extracted from, derived from, or related to the electronic message and/or the contents of the information of the electronic message. The data-records are then associated and clustered in an R-tree data structure on the basis of the index values of the dimensional parameters.  
         [0005]     The prior art R-tree data structure is formed with tree branches (i.e., hierarchically structured subsets of intermediate nodes and leaf nodes) extending from a root node. The root node contains pointers to each first node of each tree branch. Branches may contain sub-branches and leaf nodes. The data-records are linked to leaf nodes and are clustered within the R-tree at least partly on the basis of the index values of the dimensional parameters of the data-records. Bounding rectangles are posited as an abstraction of the efficiency dynamics of R-trees, wherein an n-dimensional “rectangle” structure is generated and evolved to associate data-records for more efficient storage and retrieval. The R-tree structure rules typically require that anyone node within the R-tree have a maximal number of directly subordinate nodes. As the R-tree expands to contain more information, the nodes will split as required to not exceed the limitation of directly subordinate nodes while organizing the nodes within prior art rules for selecting and modifying the bounding dimensions of the nodes to support efficient storage, discovery and retrieval of data.  
         [0006]     Information stored in electronic messages and records generated by a computer, or received by the computer via a computer network, are often stored within data-records that are first stored in a main memory of the computer and then transferred for archival into a secondary memory, such as an optical or magnetic data storage device. The method by which the data-records are associated and recorded in both the main memory and the secondary memory can significantly determine the efficiency, with which information contained within these data-records is stored, searched for, accessed, and retrieved.  
         [0007]     The efficient operation of a computer typically requires availability of the storage capacity of the main memory in order to execute numerous critical processes. It is therefore a general principle of computer design and operation that the storage capacity of the main memory not be committed to archiving information, but rather that the main memory remain generally as available as possible for use by the central processing unit.  
         [0008]     In contrast, the secondary memory of a computer is usually configured to provide memory capacity sufficient for archiving large volumes of information. Secondary memories are typically less costly than main memories on a cost per storage capacity comparison, but secondary memories also usually perform at a slower rate of accessibility by the central processing unit of the computer. In addition, the organization of the information as stored in a secondary memory can effect the time required to successfully conclude the search and retrieval of elements of the information from the secondary memory.  
         [0009]     Most computers and information network devices generate a plurality of records of their activity and of the activity of users and network traffic. For example, computers may log users&#39; access, network routers may log executed and observed traffic activity, and computer intrusion detection systems may log suspected malicious activity. Such data may be voluminous and organizations sometimes desire to store records of intrusion detection information and information system activity for months or years. The archives of electronic records containing information are often therefore stored on peripheral devices that have expandable storage capacity.  
         [0010]     It is therefore a long-felt need in the art to provide systems and methods that enable improved time efficiency in the searching, locating and analysis of data-records of information, such as information technology network activity and security events.  
       SUMMARY OF THE INVENTION  
       [0011]     Towards this object, and other objects that will become obvious in light of the Prior Art and the present disclosure, the Method of the Present Invention provides a system and method to organize and store data by means of information technology systems, such as a computer and an electronic communications network.  
         [0012]     According to the Method of the Present Invention, the data is associated in a data structure in a main memory of a computer in a methodology that increases the likelihood that information closely related within the data structure will be of interest to a same query. Segments of the data structure are then defined and separated from the main memory and stored in contiguous series of memory locations within a secondary memory, e.g., an optical or magnetic disk.  
         [0013]     In a first preferred embodiment of the Method of the Present Invention (hereafter “first method”) a computer receives information contained within one or more electronic messages and stores some or all of the information in formatted data-records (hereafter “events”). Each event includes, information, an index value T_E of a time parameter T, and at least one additional index value. The index values of the events may be parametric values or value indications that may be either extracted or derived from an electronic message and/or the information contained in an electronic message, and/or other information related to the message, an information technology activity, or an information technology system.  
         [0014]     The events may be stored in a tree data structure, e.g., an R-tree or other suitable data tree structures known in the art, and immediately maintained in a main memory of the computer. The nodes of the tree contain one or more index value pairs that include the minimum and maximum values of selected index values of all events subordinate to the instant event. Each node may contain a time-parameter index value pair of T_E values comprising the most recent time value T_R and the most aged value T_A of all events subordinate to the instant node.  
         [0015]     As the tree increases in size, branches and sub-branches are defined as segments and separated from the tree. Each segment is serialized for storage in a separated and individuated contiguous block of memory locations of a secondary memory. The contiguous block of memory locations storing a serialized segment may, in certain alternate preferred embodiments of the present invention, be located on a data storage disk of a secondary memory.  
         [0016]     In certain preferred alternate embodiments of the Method of the Present Invention a data tree is generated and maintained within a main memory of a computer wherein the root, branch and intermediate nodes are generally constrained to have at least two and typically no more than six directly subordinate nodes, and the leaf nodes of the tree are generally constrained to have at least two and typically no more than six associated events. As events are added to the data tree of the main memory and the rules governing the generation of the data tree require that nodes be split, the two nodes resulting from the split, and optionally at least some of the nodes subordinate to these two resultant nodes, are examined to identify and select segments of the tree for storage in a secondary memory of the computer. Nodes thereby examined and meeting the conditions of (a.) requiring a memory size within the bounds of an M_MAX memory size and an M_MIN memory size to store the examined node and all nodes and events subordinate to the examined node in the secondary memory, and (b.) having a T_R less than a certain T_E time value, and are then identified as defining a segment of the tree suitable for archiving in the secondary memory. A segment extending from an instant node may thus be selected for secondary memory storage, the segment comprising the instant node and that node&#39;s subordinate nodes and events. A selected segment is serialized for storage within a contiguous block of memory locations of the secondary storage, and the serialized segment is read into the secondary memory. The memory locations of the main memory used to store the nodes and events of the segment are made available for use by the computer.  
         [0017]     Alternatively or additionally, certain still alternate preferred embodiments of the Method of the Present Invention further comprise a technique for selecting segments of a data tree without requiring the occurrence of a node split. One or more nodes of a data tree may be examined to identify segments requiring no more than M_MAX contiguous storage locations in the secondary memory, and optionally (a.) having a T_R index value less than a certain time value, and/or (b.) requiring at least M_MIN contiguous storage locations in the secondary memory. The transfer of events from storage in the main memory to archiving in the secondary memory may be motivated by intent to more rapidly clear the main memory for access by the computer in performing other operations, and/or where the main memory is reaching an overload state.  
         [0018]     In certain yet alternate preferred embodiments, at least some events, and/or electronic messages from which events are at least partially extracted or derived, are received by the computer via an electronics communications network, e.g. the Internet or a telephony system.  
         [0019]     Certain additional alternate preferred embodiments of the Method of the Present Invention comprise an R-tree instantiated within the main memory . . . .  
         [0020]     The foregoing and other objects, features and advantages will be apparent from the following description of the preferred embodiment of the invention as illustrated in the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]     These, and further features of the invention, may be better understood with reference to the accompanying specification and drawings depicting the preferred embodiment, in which:  
         [0022]      FIG. 1  is a schematic diagram of an R-Tree data structure has created and maintained in accordance with the first method;  
         [0023]      FIG. 2  is a schematic of a node format of the R-Tree of  FIG. 1 ;  
         [0024]      FIG. 3  is a schematic of an event stored in the R-Tree of  FIG. 1 ;  
         [0025]      FIG. 4  is a schematic of a computer having a main memory storing the R-Tree of  FIG. 1 ;  
         [0026]      FIG. 5  is a schematic of electronic communications network comprising the computer of  FIG. 4  and communicatively coupled with the Internet;  
         [0027]      FIG. 6  is a schematic of a security event format that may be stored in the R-tree of  FIG. 1 ;  
         [0028]      FIG. 7  is a process chart of the first method that is executable by means computer of  FIG. 4 ;  
         [0029]      FIGS. 8A and 8B  are a flowchart of a method of selection of a segment of the R-Tree of  FIG. 1  for storage on a secondary memory of the computer of  FIG. 4  in accordance with the first method;  
         [0030]      FIG. 9  illustrates a method for serializing a segment of the R-Tree of  FIG. 1  for storage in the secondary memory of the computer of  FIG. 4 ;  
         [0031]      FIG. 10  is a flowchart of a variation of the first method that includes a process of transferring branches and sub-branches, i.e. segments of the R-Tree of  FIG. 1  from the main memory to the secondary memory of the computer of  FIG. 4  when the main memory is reaching an overload state;  
         [0032]      FIG. 11  is an alternate variation of the process of  FIG. 10  wherein serialized segments requiring a memory size no greater than M_MAX inclusively and having a set maximum T_R;  
         [0033]      FIG. 12  is an alternate variation of the process of  FIG. 10  wherein serialized segments requiring a memory size between M_MIN and M_MAX inclusively may be stored without regard for the T_R value of the segment; and  
         [0034]      FIG. 13  is a schematic of a serialized segment of the R-Tree of  FIG. 1  as stored in a block of contiguous memory locations of a data storage disk of the computer of  FIG. 4 . 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0035]     The following description is provided to enable any person skilled in the art to make and use the invention and sets forth the best modes contemplated by the inventor of carrying out his or her invention. Various modifications, however, will remain readily apparent to those skilled in the art, since the generic principles of the Present Invention have been defined herein.  
         [0036]     Referring now generally to the Figures and particularly to  FIG. 1 ,  FIG. 1  is a schematic diagram of an R-Tree data structure R 2  (hereafter “R-Tree”) that is instantiated and maintained in accordance with the first method and the prior art. The R-tree R 2  includes a plurality of nodes N 2 -N 8 , to include a root node N 2 , branch nodes N 4 , intermediate nodes N 6 , leaf nodes N 8  and events E. These R-tree nodes N 2 -N 8  and events E form branches R 4  and sub-branches R 6 .  
         [0037]     It is understood that each event E is subordinate to an individual leaf node N 8 , except in rare cases where an event E is immediately subordinate to a branch node N 4 , or even more rarely where an event E is immediately subordinate to a root node N 2 . The term “subordinate” is defined herein to indicate a relationship existing between two nodes wherein a first and superior node is linked by one pointer P 1 -P 6  of a node  4 - 8 , or a chain of pointers P 1 -P 6  of intermediate nodes N 6 , to a memory address of a second node, whereby the second node is subordinate to the first node. In particular, all branch nodes N 4  are subordinate to the root node N 2 . Each intermediate node N 6  is subordinate to both the root node N 2  and one and only one branch node N 4 , and possibly one or a plurality of intermediate nodes N 6 . Each leaf node N 8  is subordinate to the root node N 2 , no more than one branch node N 4 , and possibly one or more intermediate nodes N 6 .  
         [0038]     Each R-tree branch R 4  includes an originating branch node N 4  and all intermediate nodes N 6 , leaf nodes N 8  and events E subordinate to the instant originating branch node N 4 . Each R-tree sub-branch R 6  includes an originating intermediate node N 6  and all intermediate nodes N 6 , leaf nodes N 8  and events E subordinate to the instant originating intermediate node N 6 .  
         [0039]     For the sake of clarity, certain intermediate nodes R 6  are shown in  FIG. 1  without subordinate leaf nodes N 8  or events E; the suppression of these symbols is affected in  FIG. 1  to reduce the complexity of the  FIG. 1  by eliminating repetitive detail.  
         [0040]     Referring now generally to the Figures and particularly to  FIGS. 1 and 2 ,  FIG. 2  is a schematic of a possible data structure N of a node N 2 -N 8 . In the first method, each node N 2  through N 8  conforms to a prior art R-tree data structure and is identified by an identifier ID  2 . The node contains index value pairs IVP 1  through IVP 8  and pointers P-P 6 . It is understood that the number of index value pairs IV 1 - 8  and pointers P 1 -P 6  contained in each node N 2 -N 8  may vary in various alternate preferred embodiments of the Method of the Present Invention. The pointers P 1 -P 6  of the root node N 2 , branch nodes N 4  and intermediate nodes N 6  are, or comprise, memory addresses in a main memory C 2  of a computer C 4  (as per  FIG. 4 ) where subordinate nodes N 2 -N 8  and subordinate events E are at least temporarily stored. The pointers P 1 -P 6  of the leaf nodes N 8  are, or comprise, memory addresses in the main memory C 2  where events E are recorded. Each value S of the nodes N 2 -N 8  indicate the quantity of memory size required in the secondary memory C 6  to store the instant node N 2 -N 8 , all subordinate nodes N 4 -N 8 , and all subordinate events. The S value of a selected node N 2 -N 8  may be examined by the computer C 4  to determine if a branch R 4  or a sub-branch R 6  originated by the selected node N 2 -N 8  and its subordinate nodes N 4 -N 8  and events E may be stored as a serialized segment SB (as per  FIG. 13 ) in temporarily in a cache memory C 7  and also in a contiguous series of memory locations of the secondary C 6  of the computer C 4 .  
         [0041]     Referring now generally to the Figures and particularly to  FIG. 3 , each event E contains an event identifier ID-E, a plurality of Index Values I 1  through I 8  and one or more information D 1 -D 7 . The index values I 1 -I 8  and the information D 1 -D 7  may be extracted from and/or partially derived from an electronic message M (as per  FIG. 5 ). The index value I 1  is the event time value T e.    
         [0042]     Referring now generally to the Figures and particularly to  FIGS. 4 and 5 ,  FIG. 4  is a schematic of the computer C 4  of the electronic communications network NT 2  of  FIG. 5 . The R-Tree R 2  is instantiated and maintained in the main memory C 2  of the computer C 4 . The computer C 4  also includes a central processing unit C 8  comprising the cache memory C 7 , a network interface C 10 , the main memory C 2  and the secondary memory C 6 . Either of the segments ST 2  and ST 4  (as per  FIG. 1 ) may be separated from the R-tree R 2 , serialized by the computer C 4  and one of the stored in a contiguous block B of a data storage disk C 12  of the secondary memory C 6 . The serialized segment SB of the R-tree R 2  may be stored in the cache memory C 7  prior to writing the serialized segment SB to the secondary memory C 6 .  
         [0043]     A communications bus C 14  of the computer system C 4  bi-directionally communicatively couples the central processing unit C 8 , the cache memory C 7 , the network interface C 10 , the main memory C 2  and the secondary memory C 6 . The secondary memory C 6  includes the data storage disk C 12 , a disk motor C 16  and a controller C 18 . The controller C 18  reads and writes data to and from the data storage disk C 12  and the central processing unit C 8  (hereafter “CPU” C 8 ). The controller C 18  additionally directs the operations of the disk motor C 16  to enable the reading and writing to and from the data storage disk C 12 .  
         [0044]     The main memory C 2  of the computer system C 4  includes high speed memory electronics that are typically more expensive that the components of the secondary memory C 6 . The main memory C 2  may also be used by the computer system C 4  to execute a variety of computational functions, such as running an operating system of the computer system C 4  and performing basic input-output operating system functions.  
         [0045]     The secondary memory C 6  may be a lower cost memory storage device, such as a peripheral device that includes a library of one or more optical or magnetic memory disks C 12 . A contrast of the qualities and characteristics of the main memory C 2  and the secondary memory C 6  of the computer system C 4  typically surfaces these common, but not necessary, distinctions: 
        the CPU C 8  reads from and writes to the main memory C 2  faster than to the secondary memory C 6 ;     the main memory C 2  is required for use by the CPU  10  in performing critical operational functions and can not be dedicated solely to storage of events E;     the memory capacity of the secondary memory C 6  may be more easily and less expensively increased than the memory capacity of the main memory C 2  may be expanded; and     the secondary memory C 6  may be provided in certain preferred embodiments of the method of the present invention as one or more peripheral devices, libraries of magnetic or optical disks C 12 , and/or memory storage systems C 20  coupled with the communications network NT 2  (as per  FIG. 5 ).        
 
         [0050]     Referring now generally to the Figures and particularly to  FIG. 5 ,  FIG. 5  presents an electronic communications network NT 2  including the computer system C 4  and memory storage systems C 20 . The communications network NT 2  may be communicatively coupled with an external computer network NT 4 . The communications network NT 2  and the external computer network NT 4  are capable of supporting digital electronics message traffic and may be, comprise, or be comprised within, an electronics communications network such a telephony network, a computer network, an intranet, and an extranet and/or the Internet NT 6 .  
         [0051]     A plurality of network computers NT 8  of the communications network NT 2  receive electronic messages M originating from within the communications network NT 2 , from the external computer network NT 4  and/or the Internet NT 6 . Optionally, additionally or alternatively, one or more electronic messages M of the message traffic received by the computer C 4  may be generated by the computer C 4  itself, one of the network computers NT 8 , the Internet NT 6 , and/or the external computer network NT 4 .  
         [0052]     One or more messages M may optionally contain information that related to the activity of the communications network NT 2 , external network NT 4 , an unauthorized attempt of intrusion targeting the communications network NT 2 , and/or a possible unauthorized attempt of intrusion targeting the communications network NT 2 .  
         [0053]     The computer C 4  may receive events E, and alternatively or additionally messages M from which events E may be at least partially derived. The events E and the messages M may be communicated to the computer C 4  from the external computer network NT 4  and/or the network computers NT 8  via the communications network NT 2 . The communications network NT 2  and the external computer network NT 4  may be, comprise, or be comprised within, an electronics communications network such a telephony network, an intranet, and extranet and/or the Internet NT 6 .  
         [0054]     Referring now generally to the Figures and particularly to  FIG. 3 , each event E contains a plurality of index values I 1  through I 8  and one or more information D 1 -D 7 . The syntax of the event E organizes the storage of index values I 1  through I 8  of individual and separate bounding dimensions, including a time dimension I 1 , and optionally other data, such as representations of information contained in an electronic message M associated with a related security event. When generated under communications protocols common to Internet NT 6  communications, an electronic message M may contain messaging information in conformance with the Internet Protocol (hereafter “IP”). For example, an electronic message M received by a network computer NT 8  from the Internet NT 6  via the external computer network NT 4  may contain the index values I 1 -I 8  of a time T dimension I 1 , an event type ET dimension I 2 , an IP source address I 3 , and IP destination address I 4 , and a destination port number I 5 , sourcing switch/physical port dimension I 6 , event priority dimension I 7 , and optionally one or more an additional dimensions I 8 .  
         [0055]     Referring now generally to the Figures and particularly to  FIGS. 2 and 3 , each index value pair IVP 1 -IVP 8  of each node R 2 - 8  contains maximum index values I 1   max -I 8   max  and minimum index values I 1   min -I 8   min  of one distinct bounding dimension. The values I 1   max -I 8   max  and I 1   min -I 8   min  of the index value pairs IVP 1 -IVP 8  of each node N 2 -N 8  are bounding values of the dimensions of all subordinate nodes N 4 -N 8  and events E of the instant node N 2 -N 8 . For example, I 1   min  and I 1   max  are respectively minimum and maximum index values of the time dimension T and I 2   min  and I 2   max  are respectively minimum and maximum index values of the event type ET dimension.  
         [0056]     In the case of the root node N 2 , the maximum index values Imax 1 -Imax 8  are each the highest value of the relevant dimension held by any event E stored within the data tree R 2 . The pairs of parametric values IVP 1 -IVP 8  contain in the first method according to the following dimensions: 
        IVP 1 —time dimension, where I 1   max  (or “T_R”) is the most recent time value and I 1   min  (or “T_A”) is the most previous time value of all of the events stored in the R-Tree R 2 ;     IVP 2 —event ET dimension, where I 2   max  is the alpha-numerically largest event type ET designator and I 2   min  is the alpha-numerically smallest event type ET designator of all of the events stored in the R-Tree R 2 ;     IVP 3 —source IP address dimension, where I 3   max  is the alpha-numerically largest source IP designator and I 3   min  is the alpha-numerically smallest source IP designator of all of the events stored in the R-Tree R 2 ;     IVP 4 —destination IP address dimension, where I 4   max  is the alpha-numerically largest source IP address designator and I 4   minx  is the alpha-numerically smallest source IP address designator of all of the events stored in the R-Tree R 2 ;     IVP 5 —destination IP port dimension, where I 5   max  is the alpha-numerically largest source IP port designator and I 5   min  is the alpha-numerically smallest source IP port designator of all of the events stored in the R-Tree R 2 ;     IVP 6  sourcing switch/physical port dimension, where I 6   max  is the alpha-numerically largest sourcing switch/physical port designator and I 6   min  is the alpha-numerically smallest sourcing switch/physical port designator of all of the events stored in the R-Tree R 2 ;     IVP 7 —event priority dimension, where I 7   max  is the alpha-numerically largest event priority designator and I 7   min  is the alpha-numerically smallest event priority designator of all of the events stored in the R-Tree R 2 ; and     IVP 8 —additional dimension, where I 8   max  is the alpha-numerically largest designator and I 8   min  is the alpha-numerically smallest designator of an additional dimension of all of the events stored in the R-Tree R 2 .        
 
         [0065]     The index values stored in the nodes N 2 -N 8  stored within the data tree R 2  are interpreted in accordance with the first method as bounding dimensions IVP 1 -IVP 8  of index values I 1 -I 8  of distinct dimensions in accordance with the prior art operation of R-tree generation, use and maintenance.  
         [0066]     In the case of each branch node N 4  of the exemplary R-tree R 2  of  FIG. 1 , the maximum index values Imax 1 -Imax 8  are each the highest value of the relevant dimension held by any event E subordinate to the relevant branch node N 4 . The pairs of parametric values IVP 1 -IVP 8  of each branch node N 4  contain, and in accordance with the first method, the following dimensions: 
        IVP 1 —time dimension, where I 1   max  is the most recent time value T_R and I 1   min  is the most previous time value T_A of all of the events E subordinate to the branch node N 4 ;     IVP 2 —event dimension, where I 2   max  is the alpha-numerically largest event type designator and I 2   max  is the alpha-numerically smallest event type designator EVENT TYPE of all of the events E subordinate to the branch node N 4 ;     IVP 3 —source IP address dimension, where I 3   max  is the alpha-numerically largest source IP designator and I 2   min  is the alpha-numerically smallest source IP designator of all of the events E subordinate to the branch node N 4 ;     IVP 4 —destination IP address dimension, where I 4   max  is the alpha-numerically largest source IP address designator and I 4   min  is the alpha-numerically smallest source IP address designator of all of the events E subordinate to the branch node N 4 ;     IVP 5 —destination IP port dimension, where I 5   max  is the alpha-numerically largest source IP port designator and I 5   max  is the alpha-numerically smallest source IP port designator of all of the events E subordinate to the branch node N 4 ;     IVP 6  sourcing switch/physical port dimension, where I 6   max  is the alpha-numerically largest sourcing switch/physical port designator and I 6   min  is the alpha-numerically smallest sourcing switch/physical port designator of all of the events E subordinate to the branch node N 4 ;     IVP 7 —event priority dimension, where I 7   max  is the alpha-numerically largest event priority designator and I 7   min  is the alpha-numerically smallest event priority designator of all of the events E subordinate to the branch node N 4 ; and     IVP 8 —additional dimension, where I 8   max  is the alpha-numerically largest designator and I 8   min  is the alpha-numerically smallest designator of an additional dimension all of the events E subordinate to the branch node N 4 .        
 
         [0075]     In the case of each intermediate node N 6  of the exemplary R-tree R 2  of  FIG. 1 , the maximum index values Imax 1 -Imax 8  are each the highest value of the relevant dimension held by any event E subordinate to the relevant intermediate node N 6 . The pairs of parametric values IVP 1 -IVP 8  contain, and in accordance with the first method, the following dimensions: 
        IVP 1 —time T dimension, where I 1   max  is the most recent time value T_R and I 1   min  is the most previous time value T_A of all of the events E subordinate to the intermediate node N 6 ;     IVP 2 —event type ET dimension, where I 2   max  is the alpha-numerically largest event type designator and I 2   min  is the alpha-numerically smallest event type designator of all of the events E subordinate to the intermediate node N 6 ;     IVP 3 —source IP address dimension, where I 3   max  is the alpha-numerically largest source IP designator and I 2   min  is the alpha-numerically smallest source IP designator of all of the events E subordinate to the intermediate node N 6 ;     IVP 4 —destination IP address dimension, where I 4   max  is the alpha-numerically largest source IP address designator and I 4   min  is the alpha-numerically smallest source IP address designator of all of the events E subordinate to the intermediate node N 6 ;     IVP 5 —destination IP port dimension, where I 5   max  is the alpha-numerically largest source IP port designator and I 5   min  is the alpha-numerically smallest source IP port designator of all of the events E subordinate to the intermediate node N 6 ;     IVP 6  sourcing switch/physical port dimension, where I 6   max  is the alpha-numerically largest sourcing switch/physical port designator and I 6   min  is the alpha-numerically smallest sourcing switch/physical port designator of all of the events E subordinate to the intermediate node N 6 ;     IVP 7 —event priority dimension, where I 7   max  is the alpha-numerically largest event priority designator and I 7   min  is the alpha-numerically smallest event priority designator of all of the events E subordinate to the intermediate node N 6 ; and     IVP 8 —additional dimension, where I 8   max  is the alpha-numerically largest designator and I 8   min  is the alpha-numerically smallest designator of an additional dimension all of the events E subordinate to the intermediate node N 6 .        
 
         [0084]     In the case of each leaf node N 8  of the exemplary R-tree R 2  of  FIG. 1 , the maximum index values Imax 1 -Imax 8  are each the highest value of the relevant dimension held by any event E Subordinate to the relevant leaf node N 8 . The pairs of parametric values IVP 1 -IVP 8  contain, and in accordance with the first method, the following dimensions: 
        IVP 1 —time T dimension, where I 1   max  is the most recent time value T_R and I 1   min  is the most previous time value T_A of all of the events E subordinate to the leaf node N 8 ;     IVP 2 —event type ET dimension, where I 2   max  is the alpha-numerically largest event type designator and I 2   min  is the alpha-numerically smallest event type designator of all of the events E subordinate to the leaf node N 8 ;     IVP 3 —source IP address dimension, where I 3   max  is the alpha-numerically largest source IP designator and I 3   min  is the alpha-numerically smallest source IP designator of all of the events E subordinate to the leaf node N 8 ;     IVP 4 —destination IP address dimension, where I 4   max  is the alpha-numerically largest source IP address designator and I 4   min  is the alpha-numerically smallest source IP address designator of all of the events E subordinate to the leaf node N 8 ;     IVP 5 —destination IP port dimension, where I 5   max  is the alpha-numerically largest source IP port designator and I 5   min  is the alpha-numerically smallest source IP port designator of all of the events E subordinate to the leaf node N 8 ;     IVP 6  sourcing switch/physical port dimension, where I 6   max  is the alpha-numerically largest sourcing switch/physical port designator and I 6   min  is the alpha-numerically smallest sourcing switch/physical port designator of all of the events E subordinate to the leaf node N 8 ;     IVP 7 —event priority dimension, where I 7   max  is the alpha-numerically largest event priority designator and I 7   min  is the alpha-numerically smallest event priority designator of all of the events E subordinate to the leaf node N 8 ; and     IVP 8 —additional dimension, where I 8   max  is the alpha-numerically largest designator and I 8   min  is the alpha-numerically smallest designator of an additional dimension all of the events E subordinate to the leaf node N 8 .        
 
         [0093]     Referring now generally to the Figures and particularly to  FIG. 6 , in certain alternate variations of the Method of the Present Invention, the network computers NT 8  are programmed to detect unauthorized intrusion attempts. To this end, the network computers NT 8  analyze the contents of electronic messages M and generate security events E.S containing security event information when an incoming electronic message M has indications of being part of an attempted intrusion.  
         [0094]     In certain prior art methods of intrusion detection, information stored in an electronic message M or associated with the conditions of receipt of the electronic message M are compared against a library L of intrusion indications stored in the network NT 2 , and an intrusion detection security event E.S is generated when a match is found between one or more entries of an intrusion indication library L and a particular electronic message M. For example, the intrusion detection library L may contain a plurality of signatures of known or suspected indications that the electronic message M may contain at least part of a software worm or virus. When a match is found between an electronic message M and an intrusion detection signature a security event E.S is generated by a network computer NT 8 , where the security event E.S is formatted as illustrated in  FIG. 3  and comprises: 
        a. an event identifier field ID-E;     b. a time field E 1 , containing an I 1  time index value;     c. event type field E 2 , containing an I 2  ET index value;     d. source IP field E 3 , containing an I 3  index value;     e. destination IP field E 4 , containing an I 4  index value;     f. destination port field E 5 , containing an I 5  index value;     g. sourcing switch/physical port field E 6 , containing an I 6  index value;     h. event priority field E 7 , containing an I 7  index value; and     i. message information field(s) E 8 , containing an I 8  index value.        
 
         [0104]     The time field E 1  contains the index value I 1  specifying a time of generation of the event. The event type field E 2  stores an identification of type of intrusion event indication that matched the electronic message M. The source IP field E 3  stores the source IP address designated by the electronic message. The destination IP field E 4  records the destination IP address designated by the electronic message. The destination port field E 5  stores the destination port designated by the electronic message. The sourcing switch/physical port E 6  contains the switch or physical port from which the electronic message was received by the network computer  8  or as was designated by the electronic message. The event priority field E 7  records a priority assigned by the network computer NT 8  to the security event E.S. One or more message information fields E 8  store information stored in, derived from, or related to, the electronic message M, such as raw text as originally contained in the electronic message from which the security event E.S was derived.  
         [0105]     In various alternate preferred embodiments of the Method of the Present Invention, one or more messages M may be, comprise, or be comprised within, one more events E and/or security events E.S. Optionally or additionally, the computer system C 4  may derive index values I 1 -I 8  from information related to an event E and thereupon associate the generated index values I 1 -I 8  with the event E from which the index values I 1 -I 8  were derived. It is understood that the scope of the term “event” as claimed herein encompasses both events E and security events E.S.  
         [0106]     Referring now generally to the Figures and particularly to  FIG. 7 ,  FIG. 7  is a process chart of the first method that is executable by means computer C 4  of  FIG. 4 . In step  7 .A the computer C 4  is powered up. In step  7 .B the format for the events E are established. In option step  7 .C of  FIG. 6  of the security events E.S is established. In step  7 .D the R-tree R 2  is instantiated. In step  7 .E the computer C 4  determines if events E &amp; E.S shall be to the secondary memory C 6  in an expedited process of  FIG. 10, 12 , or  12 . If the computer C 4  determines to expedite the process of selecting transferring segments ST 2  and ST 4  from the main memory C 2  to the secondary memory C 6 , the computer C 4  proceeds on to a step selected from step  10 .A of  FIG. 10 , step  11 .A of  FIG. 11 , or step  12 .A of  FIG. 12 . If not proceeding on to steps  10 .A,  11 .A or  12 .A, the computer C 4  proceeds to execute step  7 .F to receive a message M, an event E or a security event E.S via the communications network NT 2 . In optional step  7 .G the message M. event E or security event E.S are processed and modified, wherein the computer C 4  may execute instructions related or unrelated to the storage of the event E, as well as generating or modifying index values I 1 -I 8  and other content of the event E. In step  7 .H the event E is instantiated as the event E will be stored. The event E, which may be a security event E.S and/or at least partially derived from a message M as received in step  7 .F, is stored in the R-tree R 2 , and the index value pairs IVP 1 -IVP 8  of the nodes N 2 -N 8  of the R-tree R 2  are updated.  
         [0107]     In step  7 .J the computer determines if the addition of the event E as performed in step  7 .H caused a node N 2 -N 8  to split, as directed by prior art R-tree methodology. Where the computer C 4  determines that a node split has occurred, the computer C 4  proceeds on to step  8 A of  FIG. 8 . Where no node split is detected by the computer C 4 , the computer C 4  proceeds on to step  7 .K to determine if the reception, creation and storage of events E shall continue.  
         [0108]     Referring now generally to the Figures and particularly to  FIGS. 8A and 8B ,  FIGS. 8A and 8B  are a flowchart of a method of selection of a segment SB of the R-Tree of  FIG. 1  for storage on a secondary memory of the computer of  FIG. 4  in accordance with the first method. In step  8 .A the two nodes N 2 -N 8  of a node split (of step  7 .H) are identified. In step  8 B a first node N 2 -N 8  of the nodes split in step  7 .I (of  FIG. 7 ) is examined to determine if the maximum T_R index value held as the I 1   max  index value of the time IVP 1  of the first node of the split is less recent than a specified time T_ 0 . If the I 1   max  index value of the first split node is T_ 0 , than the computer C 4  determines in step  8 C if the Svalue of the first node is less than equal to an M_MIN value, e.g., 256 Kbytes memory locations. The computer C 4  determines in step  8 D if a branch R 4  originated by the first node is less than or equal to an M_MAX memory size, e.g, 2 Byte memory locations. If the computer C 4  determines that the branch R 4  originated by the first node of the split has an Svalue between M_MIN and M_MAX inclusive, than the computer C 4  proceeds on from step  8 D to step  9 A and to serialize and transfer the branch R 4  to the secondary memory C 6 . Alternately, if the computer C 4  proceeds from step  8 D to step  8 E and determines that the sub-branch R 6  originated by an intermediate node N 6  subordinate to the first node of the split has an Svalue between M_MIN and M_MAX inclusive, and has a T_R value less recent than T_ 0 , then the computer C 4  proceeds on from step  8 E to step  9 A and to serialize and transfer the sub-branch R 6  to the secondary memory C 6 .  
         [0109]     In step  8 F a second node N 2 -N 8  of the nodes split in step  7 .H (of  FIG. 7 ) is selected for examination. The computer C 4  determines in step  8 G if the maximum T_R index value held as the I 1   max  index value of the time IVP 1  of the second node N 2 -N 8  of the remaining node resulting from the split of step  7 I is less recent than the time T_ 0 . If the I 1   max  index value of this second resultant node of the split of step  7 I is less recent than the time T_ 0 , than the computer C 4  determines in step  8 H if the Svalue of the second node is less than equal to an M_MIN value, e.g., 256 Kbytes memory locations. The computer C 4  determines in step  8 I if a branch R 4  originated by the second node is less than or equal to an M_MAX memory size, e.g, 2 Mbytes of memory locations. If the computer C 4  determines that the branch R 4  originated by the second node of the split has an Svalue between M_MIN and M_MAX inclusive, than the computer C 4  proceeds on from step  8 I to step  9 A and to serialize and transfer the branch R 4  to the secondary memory C 6 . In addition, if the computer C 4  determines that the sub-branch R 6  originated by an intermediate node N 6  subordinate to the second node of the split has an Svalue between M_MIN and M_MAX inclusive, and has a T_R value less recent than the T time, than the computer C 4  proceeds on from step  8 J to step  9 A and to serialize and transfer the sub-branch R 6  to the secondary memory C 6 .  
         [0110]     Referring now generally to the Figures and particularly to  FIGS. 9 and 13 ,  FIG. 9  illustrates a method for serializing a segment of the R-Tree of  FIG. 1  for storage in the secondary memory of the computer of  FIG. 4 .  FIG. 13  is a schematic of the serialized segment SB as stored in cache memory C 7  or on a secondary memory C 6 . In step  9 A a serialized segment SB is instantiated in the memory C 4  and/or the cache memory C 7 . A trailer SBT and a header SBH containing a message serial number are added to the serial segment SB in step  9 B. In step  9 C the originating node R 2 -R 8  of the branch R 4  or sub-branch R 6  of the segment (as selected in step  8   d  or  8 I) and the subordinate nodes and events of the instant branch R 4  or sub-branch R 6  are read into the SB format. In step  9 D pointers linking each node to directly subordinate nodes R 4 -R 8  and events are replaced with memory location offsets OFF that maintain the links from each node R 2 -R 8  to each node R 4 -R 8  and event E. In step  9 E the trailers SBT and headers SBH are updated upon the basis of the content entered into the serialized segment SB in steps  9 C and  9 D. In step  9 F the serialized segment SB is transferred to the secondary memory controller C 16  of the secondary memory C 6  and additional information may be added to the trailer SBT and header SBH by the secondary memory controller C 16 . In step  9 G the serialized segment SB is read into the data storage disk C 12  of the secondary memory C 6  and the memory locations of the main memory C 2  used for storing the information transferred for storage in the secondary memory C 6  are released for other uses by the computer C 4 . In step  9 I the computer C 4  returns to either processing a recently split node or to step  7 K of the process of FIG. D.  
         [0111]     Referring now generally to the Figures and particularly to  FIG. 10 ,  FIG. 10  is a flowchart of a variation of the first method that includes a process of examining and possibly transferring segments ST 2  and/or ST 4  of the R-Tree of  FIG. 1  from the main memory to the secondary memory C 6  of the computer C 4  of  FIG. 4  when the main memory C 2  is reaching an overload state. The execution of the process of  FIG. 10  by the computer C 4  expedites transfer of segments ST 2  &amp; ST 4  of the R-tree R 2  from the main memory C 2  by removing any branch or sub-branch that is no larger than an M_MAX value, e.g., 2 Mbytes of memory storage, and without regard to the age of the events E transferred for archival outside of the main memory C 2 . In step  10 A a branch node N 4  is selected. In step  10 B the computer C 4  determines if the Svalue of the branch node N 4  selected in the previous step  10 A is less than or equal an M_MAX value. If the Svalue of the examined branch node N 4  is less than or equal to an M_MAX value, then the computer C 4  proceeds from step  10 B to execute step  9 A and to serialize and store a segment ST 2  derived from the branch R 4  originated by the instant branch node N 4  most recently selected in step  10 A. If the Svalue of the examined branch node N 4  of step  10 B is greater than an M_MAX value, then the computer C 4  proceeds on from step  10 B to execute step  10 C to determine if a sub-branch R 6  of the branch R 4  originated by the instant branch node N 4  is less than or equal to the M_MAX value. If a subordinate intermediate node N 6  of the most recently examined branch node N 4  is found to have an Svalue less than or equal to the M_MAX value, then the computer C 4  proceeds on to step  9 A from step  10 C to serialize and store a segment SB derived from the sub-branch R 6  selected in step  10 C. The software execution of the computer C 4  will return to step  10 D after passing from steps  10 B or  10 C to step  9 A and after executing the process of serialization process of  FIG. 9 . In step  10 E the computer C 4  determines if there are any remaining unexamined branches R 4  to analyze for immediate storage in the secondary memory C 6  and prompt removal from the main memory C 2 . The software execution flow returns to step  7 K from step  10 D after each branch R 4  of the R-tree R 2  has been examined for expedited transfer to the secondary memory C 6 .  
         [0112]     Referring now generally to the Figures and particularly to  FIG. 11 ,  FIG. 11  is an alternate variation of the process of  FIG. 10  wherein serialized segments ST 2  &amp; ST 4  requiring a memory size between M_MIN and M_MAX inclusively may be stored without a minimum memory size requirements. The execution of the process of  FIG. 11  by the computer C 4  expedites transfer of segments ST 2  &amp; ST 4  of the R-tree R 2  from the main memory C 2  by removing any branch or sub-branch that presents (a.) a T_R less a time T value, and (b.) an Svalue no larger than an M_MAX value, e.g., 2 Mbytes of memory storage, and without regard to a minimum disc storage size requirement. In step  11 C a branch R 4  of a branch node N 4  found to have an Svalue of no more than an M_MAX value and a T_R value less than a time T will be selected for serialization and archiving into the secondary memory C 6  as per the software process of  FIG. 9 . In step  11 B a sub-branch R 6  of an intermediate node N 4  found to have an Svalue of no more than an M_MAX value and, as determined in step  11 C, a T_R value less than the time T_ 0  will be selected for serialization and archiving into the secondary memory C 6  as per the software process of  FIG. 9 . The software execution of the computer C 4  will return to step  11 E after passing from step  11 C to step  9 A and after executing the process of serialization process of  FIG. 9 . The software execution flow returns from step  11 E to step  7 K when each branch R 4  and the sub-branches R 6  of the unarchived branches R 4  have each been examined for transfer to the secondary memory C 6 .  
         [0113]     Referring now generally to the Figures and particularly to  FIG. 12 ,  FIG. 12  is an alternate variation of the process of  FIG. 10  wherein serialized segments ST 2  &amp; ST 4  requiring a memory size no smaller than M_MIN n and no greater than M_MAX inclusively and without regard to a T_R value. The execution of the process of  FIG. 12  by the computer C 4  expedites transfer of segments ST 2  &amp; ST 4  of the R-tree R 2  from the main memory C 2  by removing any branch or sub-branch that presents an Svalue (a.) no smaller than and M_MIN value, e.g., 256 Kbytes of memory locations, and (b.) no larger than an M_MAX value, e.g., 2 Mbytes of memory capacity, and without regard to a T_R value of the relevant nodes N 2 -N 8 . In step  12 B a branch R 4  of a branch node N 4  found to have an Svalue both (a.) no less than an M_MIN value, and (b.) no more than an M_MAX value is selected for serialization and archiving into the secondary memory C 6  as per the software process of  FIG. 9 . In step  12 C a sub-branch R 6  of an intermediate node N 4  found to have an Svalue both (a.) no less than an M_MIN value, and (b.) no more than an M_MAX value is selected for serialization and archiving into the secondary memory C 6  as per the software process of  FIG. 9 . The software execution of the computer C 4  will return to step  12 D after passing from steps  12 B or  12 C to step  9 A and after executing the process of serialization process of  FIG. 9 . The software execution flow returns from step  12 G to step  7 K when each branch R 4  and the remaining sub-branches R 6  of the unarchived branches R 4  have each been examined for transfer to the secondary memory C 6 .  
         [0114]     Referring now generally to the Figures and particularly to  FIG. 13 ,  FIG. 13  is a schematic of a serialized segment SB of the R-Tree R 2  of  FIG. 1  as stored in a block B of contiguous memory locations of a data storage disk of the computer of  FIG. 4 . The header SBH and the trailer SBT contain size information plus serialization numbers that support or enable recovery of the serialized segment SB in the event of certain types and degrees of malfunction of the secondary memory C 6 . The serialization numbers of the header SBH and the trailer SBT further associate the serialized segment SB with the R-tree R 2  and other serialized segments ST 2  &amp; ST 4  derived from the R-tree R 2 . In addition, the size and serialization numbers of the header SBH and the trailer SBT further identify and distinguish the serialized segment SB form other serialized segments ST 2  &amp; ST 4  derived from the R-tree R 2 .  
         [0115]     The serialized segment SB further includes nodes R 2 -R 8  and events E, with the pointers P 1 -P 6  translated from memory addresses of the main memory R 4  to offsets that directly associate a node R 2 -R 8  with immediately subordinate nodes R 4 -R 8  and events E with offset counts that specify the location of the subordinate nodes N 4 -N 8  and events E stored within the same serialized segment SB.  
         [0116]     The above description is intended to be illustrative, and not restrictive. The examples given should only be interpreted as illustrations of some of the preferred embodiments of the invention, and the full scope of the invention should be determined by the appended claims and their legal equivalents. Those skilled in the art will appreciate that various adaptations and modifications of the just-described preferred embodiments can be configured without departing from the scope and spirit of the invention. The scope of the invention as disclosed and claimed should, therefore, be determined with reference to the knowledge of one skilled in the art and in light of the disclosures presented above.