Abstract:
Methods, devices, and systems for employing binary objects representing SIP messages. More specifically, a binary SIP stack is provided which allows a mechanism to enhance the efficiency of communications and more particularly to enhance the efficiency of SIP communications between SIP network elements. Also, mechanisms are provided which allow for a SIP stack to be easily and efficiently generated, transmitted over a communication network, and parsed/processed by a communication device.

Description:
FIELD OF THE INVENTION 
     The invention relates generally to communications and more specifically to messages used to facilitate communications. 
     BACKGROUND 
     Currently, Session Initiation Protocol (SIP) messages require a significant amount of processing due to their extensive headers and strings. The SIP stacks currently use objects and strings scattered throughout memory. The cost of accessing random memory addresses causes excessive cache invalidation limiting the performance of the code. Further, in order to send a SIP message, the binary representation of the message (objects and strings) must be converted back into a full text message and then parsed by the receiver side, requiring additional time for processing on both ends and limiting the communication rate. Given the advanced communication rates in other communication protocols, users may be hesitant to adopt SIP as their primary communication protocol even though it provides many additional feature offerings. 
     SUMMARY 
     Certain technologies have been developed to increase general memory efficiency. As one example, U.S. Pat. No. 6,625,718 to Steiner, the entire contents of which are hereby incorporated herein by reference, describes a self-relative pointer for use in a software data structure. This concept saves a significant amount of memory and also provides for quicker compiling/decompiling and more efficient code. Using this solution, complex objects could be passed between processes and over networks without special conversion and extra intermediate memory storage. The &#39;718 patent does not, however, address memory allocation when generating electronic communications, such as electronic messages and more particularly SIP messages nor did it address a relative store messaging cache. 
     Accordingly, there exists a need to enhance the efficiency of communications and more particularly to enhance the efficiency of SIP communications. Also, there exists a need for SIP messages that can be easily and efficiently generated, transmitted over a communication network, and parsed/processed by a communication device. 
     These and other needs are addressed by embodiments of the present invention. More specifically, the present invention, in one embodiment, provides a method of generating, in a communication device, an electronic message for transmission across a communication network, comprising: 
     allocating a contiguous memory segment of the communication device for storing electronic message data, the segment comprising a fixed portion and a variable portion; and 
     creating a pointer in the fixed portion of the memory segment that points to the variable portion of the memory segment, wherein the pointer is a self-relative pointer. 
     In accordance with at least some embodiments of the present invention, a SIP message is provided with a self-relative pointer to data (strings, headers, and/or objects) and a temporally allocated store relative to the message object. The SIP message may be interchangeable between two modes (normal mode and wire mode). In the wire mode or offset mode the SIP message is transportable as a packet over any media, medium, or communication network. The data can be transmitted to another machine or moved in memory with no building and parsing of the SIP message. In this mode, a self-relative pointer offset may be used. 
     In the normal mode, or binary mode, the SIP message is at a particular device and can be parsed into a binary object with pointers used for strings headers and other objects referenced by the message into a single contiguous memory block. The binary form of the message can be converted to the wire mode by toggling the relative pointers to the wire mode (by employing a subtract operation whereby the distance from the pointed-to memory location to the pointing memory location is determined as a scalar value). This allows the binary object to be sent over the wire to another device. On the receiving end, the pointers are converted to normal mode and the SIP message can be used immediately. Previous solutions required the SIP message be built into a text message, sent and then parsed on the receiving end. Since parsing and building are the most expensive operations in SIP messaging, embodiments of the present invention vastly increases performance and Central Processing Unit (CPU) loading. 
     Utilization of a fixed relative pointer helps increase memory efficiency. A message can be formed as a contiguous data segment composed of a fixed and variable part. In the fixed part, variable size objects, such as message header identifiers, are stored as a relative pointer to the variable part, such as header strings, arrays, and data, of the memory segment. Since fixed relative pointers are used, the variable portion may be maintained as a contiguous chunk of data. 
     As one non-limiting example, a FROM header in the SIP message is a class that has a URI and a tag. Both of these fields are variable in length so the FROM header has two pointers in the fixed part that point to the actual URI and tag string in the variable part. The message would have a relative pointer that points to the FROM header. 
     By keeping the memory segment contiguous, modern super-scaler processors can be exploited to keep the memory segment in Level 2 (L2) cache and prevent the constant L2 cache thrashing common with prior implementations. A cache line swap is 64 bytes and can delay processing by 40-80 clock cycles, that&#39;s enough to do 80-160 floating point operations. 
     Additionally, the SIP message may comprise virtual pointers that point to a virtual class that can also be allocated in the variable part of the memory segment by virtue of an empty default constructor. With an empty default constructor, the new operator can be overridden and setup a virtual table (vtable) for the class during a from-wire conversion of the relative pointers from offsets to real pointers to the variable part of the message. 
     The term “computer-readable medium” as used herein refers to any tangible storage and/or transmission medium that participates in providing instructions to a processor for execution. Such a medium may take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media includes, for example, NVRAM, or magnetic or optical disks. Volatile media includes dynamic memory, such as main memory. Common forms of computer-readable media include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, or any other magnetic medium, magneto-optical medium, a CD-ROM, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, RAM, PROM, EPROM, FLASH-EPROM, solid state medium like a memory card, any other memory chip or cartridge, a carrier wave as described hereinafter, or any other medium from which a computer can read. A digital file attachment to e-mail or other self-contained information archive or set of archives is considered a distribution medium equivalent to a tangible storage medium. When the computer-readable media is configured as a database, it is to be understood that the database may be any type of database, such as relational, hierarchical, object-oriented, and/or the like. Accordingly, the invention is considered to include a tangible storage medium or distribution medium and prior art-recognized equivalents and successor media, in which the software implementations of the present invention are stored. 
     The terms “determine,” “calculate” and “compute,” and variations thereof, as used herein, are used interchangeably and include any type of methodology, process, mathematical operation or technique. 
     The term “module” or “tool” as used herein refers to any known or later developed hardware, software, firmware, artificial intelligence, fuzzy logic, or combination of hardware and software that is capable of performing the functionality associated with that element. Also, while the invention is described in terms of exemplary embodiments, it should be appreciated that individual aspects of the invention can be separately claimed. 
     The preceding is a simplified summary of embodiments of the invention to provide an understanding of some aspects of the invention. This summary is neither an extensive nor exhaustive overview of the invention and its various embodiments. It is intended neither to identify key or critical elements of the invention nor to delineate the scope of the invention but to present selected concepts of the invention in a simplified form as an introduction to the more detailed description presented below. As will be appreciated, other embodiments of the invention are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is block diagram depicting a communication system in accordance with at least some embodiments of the present invention; 
         FIG. 2  is a block diagram depicting a first format of an electronic message in accordance with at least some embodiments of the present invention; 
         FIG. 3  is a block diagram depicting a second format of an electronic message in accordance with at least some embodiments of the present invention; 
         FIG. 4  is a block diagram depicting a series of data structures used to build a virtual class in accordance with at least some embodiments of the present invention; 
         FIG. 5  is a flow diagram depicting a message generation and transmission method in accordance with at least some embodiments of the present invention; and 
         FIG. 6  is a flow diagram depicting a message processing method in accordance with at least some embodiments of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     The invention will be illustrated below in conjunction with an exemplary communication system. Although well suited for use with, e.g., a system using a server(s) and/or database(s), the invention is not limited to use with any particular type of communication system or configuration of system elements. Those skilled in the art will recognize that the disclosed techniques may be used in any communication application in which it is desirable to increase communication efficiencies. 
     The exemplary systems and methods of this invention will also be described in relation to analysis software, modules, and associated analysis hardware. However, to avoid unnecessarily obscuring the present invention, the following description omits well-known structures, components and devices that may be shown in block diagram form, are well known, or are otherwise summarized. 
     For purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the present invention. It should be appreciated, however, that the present invention may be practiced in a variety of ways beyond the specific details set forth herein. 
     Referring now to  FIG. 1 , an exemplary communication system  100  will be described in accordance with at least some embodiments of the present invention. The communication system  100  may comprise a communication network  104  that facilitates communications between one or more communication devices  108 . 
     The communication network  104  may be any type of known communication medium or collection of communication mediums and may use any type of protocols to transport messages between endpoints. The communication network  104  may include wired and/or wireless communication technologies. The Internet is an example of the communication network  104  that constitutes and IP network consisting of many computers and other communication devices located all over the world, which are connected through many telephone systems and other means. Other examples of the communication network  104  include, without limitation, a standard Plain Old Telephone System (POTS), an Integrated Services Digital Network (ISDN), the Public Switched Telephone Network (PSTN), a Local Area Network (LAN), a Wide Area Network (WAN), a Session Initiation Protocol (SIP) network, and any other type of packet-switched or circuit-switched network known in the art. In addition, it can be appreciated that the communication network  104  need not be limited to any one network type, and instead may be comprised of a number of different networks and/or network types. Moreover, the communication network  104  may comprise a number of different communication mediums such as coaxial cable, copper cable/wire, fiber-optic cable, antennas for transmitting/receiving wireless messages, and combinations thereof. 
     The communication devices  108  may be any type of known communication or processing device such as a personal computer, laptop, Personal Digital Assistant (PDA), cellular phone, smart phone, telephone, contact center resource, or combinations thereof. The communication devices  108  may be controlled by or associated with a single user or may be adapted for use by many users (e.g., an enterprise communication device that allows any enterprise user to utilize the communication device upon presentation of a valid user name and password). In general each communication device  108  may be adapted to support video, audio, text, and/or data communications with other communication devices  108 . The type of medium used by the communication device  108  to communicate with other communication devices may depend upon the communication applications available on the communication device  108 . 
     In accordance with at least some embodiments of the present invention, the communication devices  108  may alternatively, or additionally, comprise a server, switch, gateway, router, proxy, or other type of network communication device. More specifically, the communication device  108  is not necessarily limited to user communication devices. Rather, the present invention contemplates that a communication device  108  may comprise any device capable of receiving, sending, generating, processing, and/or parsing messages. Accordingly, a communication device  108  may include user devices as well as network and/or enterprise devices. 
     As can be seen in  FIG. 1 , the communication devices  108  may be equipped with a processor  112 , memory  116 , and a network interface  120 . Certain details of the processor  112  and memory  116  are described in U.S. Pat. No. 6,625,718, the entire contents of which are hereby incorporated herein by reference. More specifically, the memory  116  may be adapted to store electronic messages in a contiguous segment of memory and that segment of memory  116  may be divided into a fixed portion and a variable portion. The fixed portion may comprise a pointer that points to associated data in the variable portion. In accordance with at least some embodiments of the present invention, the pointer in the fixed portion may be either a self-relative pointer that defines a pointed-to location in the variable portion in terms of an offset value from its own location. In other words, the address of the pointer is offset by the value of the pointer obtaining the address of the pointed-to location. 
     The memory  116  may comprise solid-state memory resident, removable or remote in nature, such as DRAM and SDRAM. Where the processor  112  comprises a controller, the memory  116  may be integral to the processor  112 . Additionally, the memory  116  may be volatile and/or non-volatile memory. 
     The processor  112  may be adapted to store messages received from the communication network  104  in memory  116  and/or prepare messages for transmission across the communication network  104  based on data stored in the memory  116 . The network interface  120  is provided to facilitate the communication device&#39;s ability to send/receive messages across the communication network  104 . In accordance with at least some embodiments of the present invention, the network interface  120  may comprise a network adapter such as a modem, a network card, an Ethernet card or Ethernet port, a USB port, a wireless adapter, or any other known type of network interface. 
     With reference now to  FIGS. 2 and 3 , additional details of an electronic message  200 ,  300  will be described in accordance with at least some embodiments of the present invention. As can be seen in  FIG. 2 , the electronic message  200  may occupy a contiguous segment of memory that is divided into a fixed portion  204  and a variable portion  208 . A header may be provided in the fixed portion  204  that points to another memory location in the variable portion  208 . The fixed portion  204  is generally used to store pointers and other relatively small amounts of data. The variable portion  208 , on the other hand, is generally used to store strings of data. However, embedded pointers  212  may also be included in the variable portion  208  that point to another memory location  216  also within the variable portion  208  of the contiguous memory segment. 
     In a normal mode, the electronic message  200  is at a particular communication device  108  and may be stored in memory  116  of such a device  108 . In this state, the message  200  may be parsed into a binary object such that additional processing based on the message contents (i.e., contents in the variable portion  208 ) can be executed by the communication device  108 . In the normal mode, the pointers in the message  200  identify a pointed-to location by actually identifying the address of the memory location. For example, if the pointed-to memory location comprises a memory address of 0X12345, then the pointer for that pointed-to memory location would actually identify the memory address 0X12345. In this mode, the distance between the pointer memory location and the pointed-to memory location is not necessarily reflected by the pointer itself. This is a traditional pointer that can be readily processed by the communication device  108 . 
     As can be seen in  FIG. 3 , however, the message  200  may be converted from the normal mode into a wire mode. Once in the wire mode or offset mode the message  300  is transportable over any media or communication medium in the communication network  104 . More specifically, if the message  300  comprises an electronic message such as a SIP message, then the message  300  is a SIP packet in the wire mode. One advantage of the wire mode is that the data in the message  300  can be transmitted to another communication device  108  or be moved in memory without any building and parsing of a SIP message. This greatly reduces the amount of processing required of the SIP message. Furthermore, in this mode, a self-relative pointer is used as opposed to the actual pointers employed in the normal mode. The self-relative pointer is a scalar value  320 ,  324  that identifies a distance between the pointer memory location and the pointed-to memory location. 
     The binary form of the message  200  can be converted into the wire-mode by toggling the pointers into self-relative pointers. This is accomplished by executing a subtract operation that subtracts the distance between the pointed-to location and the location of the self-relative pointer. Since the message is maintained in a contiguous segment of memory that is divided into a fixed portion  304  and a variable portion  308 , the self-relative pointer  320  in the fixed portion  304  identifies the actual distance in terms of memory size (e.g., 100 bytes in the example depicted in  FIG. 3 ) from the pointer location to the pointed-to location. Accordingly, the self-relative pointer can be represented as a simple scalar value  320 ,  324 . Additionally, embedded pointers  212  are also converted into self-relative pointers  312  similar to the conversion of the pointers in the fixed portion  204 ,  304 . In the example depicted in  FIG. 3 , the embedded pointer  312  comprises a scalar value  324  having a value of 10 that corresponds to the distance of 10 bytes between the pointer location and the pointed-to location  316 . 
     By keeping the message  200 ,  300  in a contiguous chunk of data, processor intensive “new” operations can be replaced with a simple check for space (i.e., space available in the contiguous memory segment), add, and return operation. This series of operations is an order of magnitude faster for allocation of a new portion of memory as compared to previous “new” operations. 
     Furthermore, in accordance with at least some embodiments of the present invention, memory is not deleted when a string or the like is removed from the message  200 ,  300 . Therefore, destructors are not necessary, thereby simplifying the operation and enhancing the speed with which the message  200  can be processed at a particular communication device  108 . 
     While the message  200 ,  300  has been described as having two distinct modes or states corresponding to two distinct forms of pointers, one skilled in the art will appreciate that distinct message states and pointer forms are not necessarily required. More specifically, embodiments of the present invention contemplate that the pointers in the message may always be in the form of self-relative pointers. In other words, the message may comprise self-relative pointers even when it is at a particular communication device  108  and/or is being processed (e.g., parsed) by that communication device  108 . Furthermore, if both communication devices  108  are capable of processing the message when that message has self-relative pointers, then the communication devices  108  may negotiate that fact during call set-up and agree to use messages with self-relative pointers. 
     With reference now to  FIG. 4 , an exemplary message  400  comprising virtual pointers will be described in accordance with at least some embodiments of the present invention. Again, the message  400  is generally provided in a contiguous segment of memory comprising a fixed portion  404  and a variable portion  408 . More specifically, the message  400  may be embodied as a SIP message that comprises virtual pointers that point to a virtual class. The virtual pointer may reside in the fixed portion  304 . Of course, the virtual pointer may also be embodied as an embedded pointer in the variable portion  408 . Furthermore, the virtual pointer may be a normal pointer or a self-relative pointer. The state of the virtual pointer (i.e., normal or self-relative) may depend upon whether the message  400  is residing at a particular communication device  108  or is being transmitted across a communication medium in the communication network  104 , although such a dependence is not necessary. 
     As can be seen in  FIG. 4 , the pointed-to location may comprise an empty default constructor that is associated with a virtual function  412 . The empty constructor may be in a virtual base class that can be used to generate a virtual table for the virtual function. Different operators (e.g., toWire operators, fromWire operations, parse operators, build operators) may be referenced by the virtual function via an index  416 . The index may identify one of the available operators in the static operator table  420  for use when the virtual class is called. Accordingly, the virtual pointer may be used to request one of many different operators in the static table  420 , and the operator selected may vary depending upon where the message resides and what operation is needed. In other words, the same virtual pointer may be used to execute a to-wire conversion of the message as well as a from-wire conversion of the message. As one example, with an empty default constructor, the “new” operator can be overridden and setup the virtual table  412  for the class during the from-wire conversion of the self-relative pointers from offsets to actual pointers that actually identify address locations in the variable portion of the message. 
     This model basically walks the data structure and executes commands as the appropriate instruction is approached in the data structure. In an alternative embodiment, the self-relative pointers may be mapped such that they can be switched relatively quickly without traversing the entire data structure. 
     Referring now to  FIG. 5 , an exemplary message generation and transmission method will be described in accordance with at least some embodiments of the present invention. The method is initiated when instructions are received to generate and send a SIP message (step  504 ). These instructions may be received directly from a user of the communication device  108  and/or may be received from an internal component of the communication device. For instance, the user may take the communication device  108  off-hook and dial a particular number. Upon completion of dialing the number the user may hit a “send” button on the device  108  or may simply wait for the communication device  108  to begin dialing automatically after a predetermined amount of time. The predetermined amount of time or the actual receipt of user input at the “send” button may correspond to instructions that initiate the method. 
     Thereafter, the method continues with the communication device  108  allocating a contiguous memory block for the message (step  508 ). The contiguous memory segment may be allocated from any type of local or remote memory. The contiguous memory block is then divided into a fixed portion and a variable portion. Pointers are then created in the fixed portion of memory that point to memory locations in the variable portion of memory (step  512 ). This allows the pointers in the fixed portion maintain a relatively small size (e.g., on the order of bits or a couple of bytes), while allowing actual data (e.g., strings, objects, headers, etc.) to be stored in the variable portion. Furthermore, the contents of the variable portion of memory may be changed or updated without altering the pointers in the fixed portion. This allows the data to be accessed relatively easily regardless of whether it has been changed or not. As noted above, pointers may also be created in the variable portion of the contiguous memory block. 
     The method continues by determining whether the message generation process is complete (step  516 ). If the message is not yet completed, then the message generation process continues (step  520 ) until it is determined that the message is fully generated (as determined in step  516 ). Once the message generation process is complete, however, the message is then prepared for transmission across the communication network  104 . To facilitate transmission across the communication network  104 , the message may be converted from a normal mode to a wire mode, whereby the pointers are transformed from normal pointers into self-relative pointers (step  524 ). This conversion may not be necessary, however, if the message was originally generated with self-relative pointers. 
     Once the message has been adequately prepared for transmission across the communication network, the method continues with the communication device  108  transmitting the message across the communication network  104  via its network interface  120  (step  528 ). 
     Referring now to  FIG. 6 , an exemplary message receiving method will be described in accordance with at least some embodiments of the present invention. The method begins when a message is received at a communication device  108  (step  604 ). The received message may then be converted from the wire mode to a normal mode. If the receiving communication device  108  needs to transform the pointers of the message to complete this conversion, then the pointers are converted from self-relative pointers to actual pointers (step  608 ). As noted above, however, the receiving communication device  108  may have negotiated with the sending communication device  108  to use self-relative pointers even during processing. In such an embodiment, the conversion of pointers from their self-relative state may not be necessary. 
     After the message has been converted to a useable format for the communication device  108 , the method proceeds with the communication device  108  processing the message and performing any necessary tasks on the message (step  612 ). The way in which the message is processed may vary depending upon the nature of the receiving communication device  108 . For instance, if the receiving communication device  108  is the target communication device  108 , then the message may be fully parsed and its payload (e.g., voice data, image data, or other types of data) may be provided or otherwise displayed to the user of the communication device  108 . If, however, the receiving communication device  108  is a communication device within the communication network  104 , then the receiving communication device  108  may process the message just enough to identify another communication device  108  to which the message should be forwarded. 
     Although embodiments of the present invention have generally discussed the generation of a SIP electronic message, those skilled in the art will appreciate that self-relative pointers may be useful for many other types of communication messages. Furthermore, although embodiments of the present invention have generally discussed the use of classes in connection with the generation and format of an electronic message. Those skilled in the art will appreciate that any type of programming language may be used to generate a message in accordance with embodiments of the present invention. More particularly, C++, Java, any object oriented programming language, native programming languages, or any combination thereof may be employed to generate messages without departing from the spirit of the present invention. 
     While the above-described flowchart has been discussed in relation to a particular sequence of events, it should be appreciated that changes to this sequence can occur without materially effecting the operation of the invention. Additionally, the exact sequence of events need not occur as set forth in the exemplary embodiments. The exemplary techniques illustrated herein are not limited to the specifically illustrated embodiments but can also be utilized with the other exemplary embodiments and each described feature is individually and separately claimable. 
     The systems, methods and protocols of this invention can be implemented on a special purpose computer in addition to or in place of the described communication equipment, a programmed microprocessor or microcontroller and peripheral integrated circuit element(s), an ASIC or other integrated circuit, a digital signal processor, a hard-wired electronic or logic circuit such as discrete element circuit, a programmable logic device such as PLD, PLA, FPGA, PAL, a communications device, such as a server, personal computer, any comparable means, or the like. In general, any device capable of implementing a state machine that is in turn capable of implementing the methodology illustrated herein can be used to implement the various communication methods, protocols and techniques according to this invention. 
     Furthermore, the disclosed methods may be readily implemented in software using object or object-oriented software development environments that provide portable source code that can be used on a variety of computer or workstation platforms. Alternatively, the disclosed system may be implemented partially or fully in hardware using standard logic circuits or VLSI design. Whether software or hardware is used to implement the systems in accordance with this invention is dependent on the speed and/or efficiency requirements of the system, the particular function, and the particular software or hardware systems or microprocessor or microcomputer systems being utilized. The analysis systems, methods and protocols illustrated herein can be readily implemented in hardware and/or software using any known or later developed systems or structures, devices and/or software by those of ordinary skill in the applicable art from the functional description provided herein and with a general basic knowledge of the communication and computer arts. 
     Moreover, the disclosed methods may be readily implemented in software that can be stored on a storage medium, executed on a programmed general-purpose computer with the cooperation of a controller and memory, a special purpose computer, a microprocessor, or the like. In these instances, the systems and methods of this invention can be implemented as program embedded on personal computer such as an applet, Java® (although the invention is not limited to these technologies), as a resource residing on a server or computer workstation, as a routine embedded in a dedicated communication system or system component, or the like. The system can also be implemented by physically incorporating the system and/or method into a software and/or hardware system, such as the hardware and software systems of a communications device or system. 
     It is therefore apparent that there has been provided, in accordance with the present invention, systems, apparatuses and methods for generating communication messages comprising a self-relative pointer. While this invention has been described in conjunction with a number of embodiments, it is evident that many alternatives, modifications and variations would be or are apparent to those of ordinary skill in the applicable arts. Accordingly, it is intended to embrace all such alternatives, modifications, equivalents and variations that are within the spirit and scope of this invention.