Petition for Inter Partes Review
`of U.S. Patent No. 9,148,493
`
`UNITED STATES PATENT AND TRADEMARK OFFICE
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`
`_____________________
`
`Avi Networks, Inc.,
`Petitioner
`v.
`Citrix Systems, Inc.,
`Patent Owner.
`
`_____________________
`
`Case No. Unassigned
`
`U.S. Patent No. 9,148,493
`
`_____________________
`
`Declaration of Kevin Jeffay
`In Support of Petitioner Avi Networks, Inc. in the
`Petition for Inter Partes Review of U.S. Patent No. 9,148,493
`
`Mail Stop PATENT BOARD
`Patent Trial and Appeal Board
`U.S. Patent and Trademark Office
`P.O. Box 1450
`Alexandria, VA 22313-1450
`
`i
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`Petition for Inter Partes Review
`of U.S. Patent No. 9,148,493
`
`TABLE OF CONTENTS
`
`I.
`II.
`
`Page
`INTRODUCTION ........................................................................................... 1
`BASIS FOR OPINIONS ................................................................................. 3
`A. Qualifications ........................................................................................ 3
`B.
`Preparation for This Declaration ........................................................... 7
`C.
`Level of Ordinary Skill in the Art ......................................................... 8
`III. LEGAL UNDERSTANDINGS ....................................................................... 8
`A. A Person of Ordinary Skill in the Art ................................................... 9
`B.
`Legal Standard for Prior Art .................................................................. 9
`C.
`Legal Standard for Anticipation ..........................................................10
`D.
`Legal Standard for Obviousness .........................................................11
`E.
`Claim Construction..............................................................................13
`IV. TECHNOLOGY BACKGROUND ...............................................................14
`A. Network Protocols and Protocol Layering ..........................................15
`B.
`Network Packets ..................................................................................32
`C.
`The TCP Transport Layer Protocol in More Detail ............................33
`D.
`Persistent Connections ........................................................................36
`E.
`Proxies and Caches ..............................................................................40
`F.
`Connection Pooling .............................................................................41
`THE ’493 PATENT .......................................................................................41
`A. Overview of the ’493 Patents ..............................................................41
`B.
`Overview of the Challenged Claims ...................................................44
`VI. PRIOR ART CONSIDERED ........................................................................48
`A.
`Identification of the Primary Prior Art References .............................49
`ii
`
`V.
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`
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`
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`B.
`
`Petition for Inter Partes Review
`of U.S. Patent No. 9,148,493
`
`General Summary of the Primary Prior Art References .....................50
`1.
`Squid Cache 2.0 ........................................................................51
`2. WO 00/28433 (“Susai”) ............................................................57
`3.
`RFC 2068 ..................................................................................59
`VII. ANALYSIS OF THE CHALLENGED CLAIMS AGAINST THE
`PRIOR ART ...................................................................................................62
`A.
`Claim Construction..............................................................................63
`B.
`Application of the Prior Art to the Claims ..........................................65
`C.
`Claims 1–5, 7, 9–13, 15, and 17–20 Are Anticipated by Squid .........66
`D.
`Claims 1–5, 7, 9–13, 15, and 17–20 Are Rendered Obvious by
`Squid ....................................................................................................81
`Claims 8 and 16 Are Rendered Obvious by Squid over RFC
`2068 .....................................................................................................82
`Claims 1–5, 7, 9–13, 15, and 17–20 Are Rendered Obvious by
`Susai over Squid ..................................................................................85
`Claims 1–5, 7–13, and 15–20 Are Rendered Obvious by Susai
`over RFC 2068 ..................................................................................107
`VIII. SECONDARY CONSIDERATIONS .........................................................131
`IX. RIGHT TO SUPPLEMENT ........................................................................131
`X.
`CONCLUSION ............................................................................................132
`
`
`
`E.
`
`F.
`
`G.
`
`
`
`iii
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`I.
`
`INTRODUCTION
`1. I, Kevin Jeffay, have been retained by Gibson, Dunn & Crutcher LLP
`
`on behalf of Petitioner Avi Networks Inc. (“Avi”) as an independent expert in this
`
`Petition for inter partes review by the U.S. Patent and Trade Mark Office. As part
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`of my engagement, I have been asked to provide analysis and expert opinions on
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`the following topics: (1) the disclosure of the U.S. Patent No. 9,148,493 (“the ’493
`
`Patent”); and (b) the validity of claims 1–5, 7–13, and 15–20.
`
`2. In my opinion, claims 1–5, 7–13, and 15–20 of the ’493 patent (“the
`
`Challenged Claims”) are invalid in view of the prior art I discuss in this
`
`Declaration. In particular, it is my opinion that the prior art discussed herein
`
`discloses, teaches, or suggests the invention claimed in the Challenged Claims,
`
`rendering the Challenged Claims invalid as anticipated by, and obvious over, the
`
`prior art. The particular references and/or combinations that invalidate the
`
`Challenged Claims, as well as the reasons for my opinions and bases thereof, are
`
`set forth in detail below.
`
`3. I am being compensated for my work on this case at my standard
`
`consulting rate of $700 per hour. I am also being reimbursed for my expenses that
`
`I may incur. My compensation is in no way contingent upon the results of my
`
`study, the substance of my testimony, or the outcome of this case.
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`
`
`1
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`4. Based upon the facts and information available to me to date, I detail
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`my opinions relevant to this petition for inter partes review. I am prepared to
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`provide expert testimony on the opinions formed herein if asked about those issues
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`by the Board or others.
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`5. Additionally, I may discuss my own work, teachings, and knowledge
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`of the state of the art in the relevant time period. I may rely on handbooks,
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`textbooks, technical literature, and the like to demonstrate the state of the art in the
`
`relevant period and evolution of the technology.
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`6. Although I express my opinions in the matter named above herein, I
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`respectfully reserve my right to alter or supplement my analysis in response to
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`criticisms or alternative opinions offered by Citrix or its experts or any other matter
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`that might cause me to alter my opinion.
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`7. It is my understanding that discovery may occur in this proceeding.
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`As a result, I reserve the right to modify or supplement my opinions, as well as the
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`bases thereof, in light of any documents, testimony, or other evidence that may
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`emerge during the course of this matter, including depositions that have yet to be
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`taken.
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`8. Throughout this declaration, I refer to specific line numbers or page
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`numbers of the relevant prior art or other technical documents. The citations are
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`
`
`2
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`intended to be exemplary and are not intended to convey that the citations are the
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`only source of evidence to support the propositions for which they are cited.
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`II. BASIS FOR OPINIONS
`A. Qualifications
`9. I am a tenured professor in the Department of Computer Science at
`
`the University of North Carolina at Chapel Hill where I currently hold the position
`
`of Gillian T. Cell Distinguished Professor of Computer Science. I also currently
`
`serve as the Chairman of the Department. I have been a faculty member at UNC
`
`since 1989.
`
`10. I received a Ph.D. in computer science from the University of
`
`Washington in 1989. Before that I received an M.Sc. degree in computer science
`
`from the University of Toronto in 1984, and a B.S. degree with Highest Distinction
`
`in mathematics from the University of Illinois at Urbana-Champaign in 1982.
`
`11. I have been involved in the research and development of networked
`
`computing systems for over 35 years. I have been a faculty member at the
`
`University of North Carolina since 1989 where I perform research and I teach in
`
`the areas of computer networks, distributed systems, real-time systems, operating
`
`systems, multimedia networking, Internet traffic measurement, and network
`
`performance evaluation, among others. A major theme of my research has been the
`
`development of technology to improve the performance of data transfers on the
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`
`
`3
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`Internet. My research has examined problems ranging from network support for
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`real-time multimedia applications such as audio and video streaming, Voice over
`
`Internet Protocol (VoIP) and Internet videoconferencing, to the design of
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`congestion control mechanisms in network routers, to network intrusion detection
`
`systems, to measurements and analysis of network traffic to passively assess the
`
`performance of servers on the Internet. In addition, I have also explored problems
`
`in the design and implementation of operating systems.
`
`12. Much of my research has been performed jointly with the industry.
`
`For example, starting in 1991, in collaboration with IBM and Intel my research
`
`group constructed and operated one of the first Internet videoconferencing systems.
`
`We also developed a data conferencing, “shared window system” that was
`
`functionally and visually equivalent to today’s Cisco WebEx and Citrix
`
`GoToMeeting screen sharing products and services.
`
`13. In much of my research I regularly build and use clusters of
`
`computers interconnected by network switches, bridges, and routers to form and
`
`evaluate experimental and production networks. For example, in the late 1990s and
`
`early 2000s, my research evolved to consider router-based mechanisms for
`
`controlling the performance of network traffic. In much of this research, my
`
`students and I built and instrumented network routers and performed large-scale
`
`experiments with this equipment. This included the design and use of devices
`
`
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`4
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`placed in-line between clients and servers in a network to passively monitor and
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`analyze network traffic. Based on these experiments, in 2003, my group at UNC
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`won the most prestigious research award for original research in computer
`
`networking. This project, and others, took place in a networking lab my students
`
`and have I constructed at UNC over a number of years. The lab consists of several
`
`hundred computers and networking devices.
`
`14. I have authored or co-authored over 100 articles in peer-reviewed
`
`journals, conference proceedings, texts, and monographs in the aforementioned
`
`areas of computer science and others. I have previously served as Editor-in-Chief
`
`for the journal Multimedia Systems and Associate Editor for the journal Real-Time
`
`Systems. In addition, I have edited and co-edited numerous published proceedings
`
`of technical conferences and have edited a book of readings in multimedia
`
`computing and networking (with Hong-Jiang Zhang) published by Morgan
`
`Kaufman. I am also a co-author (with Long Le and F. Donelson Smith) of a
`
`monograph related to computer network protocols, and a co-author (with Jay Aikat
`
`and F. Donelson Smith) of a second monograph related to experimental computer
`
`networking.
`
`15. I have served on numerous proposal review panels for the National
`
`Science Foundation and other international funding agencies in the aforementioned
`
`areas of computer science. I have served as a program chair or member of the
`
`
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`5
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`technical program committee for over 100 professional, international, and technical
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`conferences, workshops, and symposia.
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`16. I am a named inventor on four U.S. Patents. These patents are
`
`generally related to computer networking and the delivery of services over
`
`networks.
`
`17. I have served as an expert witness and technical consultant in
`
`litigation and inter partes review matters concerning computer networks,
`
`distributed systems, operating systems, multimedia networking, cellular and
`
`wireline telephony, Voice over Internet Protocol (VoIP) telephony, data center
`
`networking, embedded systems and embedded software, and real-time systems,
`
`among others. I have testified in several trials, arbitrations, and claim construction
`
`hearings as an expert witness.
`
`18. I attach as Exhibit 1 my curriculum vitae (“CV”), which includes a
`
`more detailed list of my qualifications. My CV also contains a list of all other cases
`
`in which, during the previous 4 years, I testified as an expert at trial or by
`
`deposition.
`
`Preparation for This Declaration
`B.
`19. All of the opinions that I state in this declaration are based upon my
`
`own personal knowledge and professional judgment. If called upon to testify as a
`
`
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`6
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`witness during any proceeding, I am willing and able to competently testify as to
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`anything contained in this declaration.
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`20. In forming my opinions, in addition to my own knowledge,
`
`experience, and expertise, I have reviewed and relied upon: (1) the ’493 patent; (2)
`
`the file histories of the ’493 patent and its parent applications; (3) the prior art
`
`references cited in this declaration; and (4) any other references referred to or cited
`
`in this report.
`
`C. Level of Ordinary Skill in the Art
`21. In my opinion, a person of ordinary skill in the art relating to the ’493
`
`patent would have a Bachelor’s degree in Computer Science, Computer
`
`Engineering, Electrical Engineering, or an equivalent discipline, and at least one
`
`year’s worth of experience developing client/server systems and/or application
`
`layer network communication protocols. In the alternative, I believe that a person
`
`of ordinary skill could have two or more years of work experience in computer
`
`networking and in the development of client-server systems in lieu of the education
`
`requirements.
`
`22. I meet the criteria described above and believe myself to be a person
`
`with at least ordinary skill in the art pertaining to the ’493 patent. I would have
`
`qualified as such a person by at least October 18, 2000, which I understand is the
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`earliest priority date of the ’493 patent.
`
`
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`7
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`III. Legal Understandings
`23. In this section, I describe my understanding of certain legal standards
`
`that I may have relied upon in forming my opinions set forth in this declaration. I
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`have been informed of these legal standards by Avi’s attorneys. Although I am not
`
`an attorney and have not researched the law on patent invalidity, I have formed the
`
`following understanding about the legal standards through Avi’s attorneys.
`
`A. A Person of Ordinary Skill in the Art
`24. It is my understanding that a person of ordinary skill in the art
`
`(“POSITA”) is a hypothetical person who is used to analyze the prior art without
`
`the benefit of hindsight. A person of ordinary skill in the art is presumed to be one
`
`who uses conventional wisdom in the art, but does not undertake to innovate, either
`
`by extraordinary insights or by systematic research.
`
`25. I further understand that the hypothetical POSITA is presumed to
`
`have knowledge of all references that are sufficiently related to one another and to
`
`the pertinent art, and to have knowledge of all arts reasonably pertinent to the
`
`particular problem that the claimed invention purports to address.
`
`Legal Standard for Prior Art
`B.
`26. It is my understanding that a patent, published patent application, or
`
`other publication, must first qualify as prior art before it can be used to invalidate a
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`patent claim.
`
`
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`8
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`27. I further understand that a U.S. or foreign patent qualifies as prior art
`
`to a patent claim if the date of application, issuance, and/or publication of the prior
`
`art patent is prior to the purported date of invention of the patent claim.
`
`28. I understand that a printed publication, such as a technical publication,
`
`a magazine article, or newsgroup post, qualifies as prior art to a patent claim so
`
`long as the date of publication is prior to the purported date of invention of the
`
`patent claim.
`
`29. It is my understanding, moreover, that a U.S. patent qualifies as prior
`
`art to a patent claim if the application for the prior art patent was filed in the United
`
`States before the purported date of invention of the patent claim.
`
`C. Claim Construction
`30. I understand that the USPTO recently issued a new final rule
`
`addressing the claim construction standard applied during inter partes review. The
`
`new rule replaces the “broadest reasonable interpretation” standard with the same
`
`standard that is used during claim construction in district court civil actions, with
`
`which I am familiar. I understand that this new rule applies to the IPR petition
`
`filed concurrently herewith, which means that claim construction in this IPR will
`
`be governed by the same claim construction standards utilized in district court.
`
`31. I understand that, in the district court context and in this IPR, the
`
`words of a claim are generally given their ordinary and customary meaning. This
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`
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`9
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`is the meaning the term would have to a person of ordinary skill in the art in
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`question at the time of the invention, which generally means the time the
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`application was filed.
`
`32. I further understand that the specification informs the proper
`
`interpretation of a claim. This is because a person of ordinary skill in the art is
`
`deemed to have read the claim term not only in the context of the particular claim
`
`in which the dispute term appears, but in the context of the entire patent, including
`
`the specification. I understand that the prosecution history and extrinsic evidence
`
`concerning relevant scientific principles, the meaning of technical terms, and the
`
`state of the art are also considered in ascertaining the meaning of claim terms.
`
`D. Legal Standard for Anticipation
`33. I understand that, once the claims of a patent have been construed, the
`
`second step in determining anticipation of a patent claim requires a comparison of
`
`the construed claim language to the prior art on a limitation-by-limitation basis.
`
`34. It is my understanding that a prior art reference anticipates a claim,
`
`and thus renders the claim invalid, if all elements of the claim are disclosed in the
`
`prior art reference, either explicitly or inherently.
`
`35. I further understand that, under Section 102 of the Patent Act, claims
`
`of a patent are invalid for lack of novelty if they are anticipated by a single prior art
`
`reference. I have been informed by counsel that a claimed invention is invalid as
`
`
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`10
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`anticipated and hence lacks novelty if all of the limitations of the claim as
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`construed by the Court are present in a prior art reference. It is my understanding,
`
`however, that a limitation of the claim need not be shown directly in a reference so
`
`long as POSITA would have understood the limitation to be inherent, or
`
`necessarily present in the reference.
`
`Legal Standard for Obviousness
`E.
`36. I understand that an invention may also be obvious, even though the
`
`invention is not identically disclosed or described in a single prior art reference,
`
`which is required for anticipation. This is true if the differences between the
`
`subject matter sought to be patented and the prior art are such that the subject
`
`matter as a whole would have been obvious at the time the invention was made to a
`
`person having ordinary skill in the relevant art.
`
`37. I understand the Supreme Court has urged caution in granting a patent
`
`based on the combination of elements found in the prior art. This is because a
`
`patent for a combination that only unites old elements with no change in their
`
`respective functions withdraws what already is known from the public, giving it
`
`exclusively to the patentee. The combination of familiar elements according to
`
`known methods is likely to be obvious when it does no more than yield predictable
`
`results.
`
`
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`11
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`38. I further understand that when a work is available in one field of
`
`endeavor, design incentives and other market forces can prompt variations of it,
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`either in the same field or a different one. If a person of ordinary skill can
`
`implement a predictable variation, the invention is likely obvious. For the same
`
`reason, if a technique has been used to improve one device, and a person of
`
`ordinary skill in the art would recognize that it would improve similar devices in
`
`the same way, using the technique is obvious unless its actual application is
`
`beyond his or her skill. Put another way, a court must ask whether the
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`improvement is more than the predictable use of prior art elements according to
`
`their established functions. I understand that this is a flexible standard and it is not
`
`confined to any particular formalistic conception.
`
`39. I understand that, when conducting an obviousness inquiry, the
`
`analysis should consider the scope and content of the prior art, differences between
`
`the prior art and the claims of the challenged patent claims, and the level of
`
`ordinary skill in the art. Secondary considerations of nonobviousness can also be
`
`considered. Secondary considerations include commercial success enjoyed by
`
`devices practicing the patented invention, industry praise for the patented
`
`invention, copying by others, and the existence of a long-felt but unsatisfied need
`
`for the invention. I understand that there must be a nexus between these factors
`
`
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`12
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`and the claims themselves for these secondary considerations to impact the
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`analysis of obviousness.
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`40. I understand that there generally must be a motivation to combine the
`
`references in order to find obviousness. This motivation or reason to combine can
`
`arise from the references themselves, changing market dynamics, or from simple
`
`common sense.
`
`41. I understand that a single reference can render a patent claim obvious,
`
`even if that reference does not fully anticipate the claim. To determine whether
`
`there was an apparent reason to combine the known elements in the way a patent
`
`claims, it will often be necessary to look to interrelated teachings of multiple
`
`patents; to the effects of demands known to the design community or present in the
`
`marketplace; and to the background knowledge possessed by a person having
`
`ordinary skill in the art.
`
`IV. TECHNOLOGY BACKGROUND
`42. To put in context my opinions on the validity of the claims of the ’493
`
`patent, in this section I provide some background on computer networking with a
`
`particular focus on the concepts of network communication protocols, protocol
`
`layers, and data forwarding and routing.
`
`43. All of the concepts discussed in this section were well-known and
`
`widely used well prior to the October 18, 2000 priority date for the ’493 patent.
`
`
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`13
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`For example, I taught these concepts to undergraduate computer science majors for
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`over ten years prior to October 18, 2000.
`
`A. Network Protocols and Protocol Layering
`44. When one computer wishes to communicate with another computer
`
`over a computer network, hardware and software on that computer will create a
`
`message and transmit the message as a series of one or more data units to the
`
`destination computer. These data units will be formatted and processed by devices
`
`in the network (including the source and destination computers) according to a
`
`number of protocols that exist to facilitate communications over the network. Each
`
`protocol defines a “language” that a network device must “speak” in order to
`
`communicate with other devices. However, unlike human communication, to
`
`communicate messages between a source and a destination computer, each
`
`computer must use multiple protocols (languages) together to communicate.
`
`45. Network protocols are organized hierarchically as a series of hardware
`
`and software “layers” and are colloquially referred to as a “protocol stack.” Layers
`
`in the stack are numbered and commonly referred to by their layer number. The
`
`layers are numbered from the lowest, most basic or primitive protocol layer, to the
`
`highest, most functional protocol layer. Each layer is responsible for providing a
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`discrete communication service that builds upon the service(s) provided by the
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`lower layer(s) to provide a more functional, full-featured communication service to
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`upper layers. Figure 1 provides a graphical illustration of the protocol layering that
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`exists on computers that communicate over the Internet.
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`
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`Figure 1: A graphical illustration of the Internet model protocol stack.1
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`46. The lowest layer, layer-1, or “L1,” is the physical layer. The physical
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`layer protocol is typically implemented exclusively in hardware and is concerned
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`with the low-level details of transmitting binary data (“1s” and “0s”) over some
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`physical medium. The physical layer refers to the physical media used to construct
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`the network. Examples of different physical layers include fiber optic cable,
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`copper-twisted pair wiring, or radio frequency spectrum. As these are each
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`different physical media, each would require a different physical layer protocol
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`because the process of transmitting binary data on the medium is different for each
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`type of media.
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`
` 1 As of the earliest possible priority date of the ’493 patent, the five-layer Internet
`model was by far the dominant protocol stack. Nonetheless, a more complex
`seven-layer stack, called the OSI model, also existed. Given the disclosures in
`the ‘493 patent, for purposes of this declaration it will suffice to focus on the
`simpler five-layer Internet model.
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`47. The next layer in the protocol stack, layer-2, or “L2,” is the data link
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`layer (or simply the link layer). The link layer defines a transmission structure,
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`typically called a frame, and is responsible for transmitting frames between
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`computers on the same network. The most common example of a link layer
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`protocol is the Ethernet protocol. Layer 2 protocols are used to communicate
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`between computers on the same local-area network (LAN). To communicate
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`between two computers on different LANs a higher layer protocol is needed.
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`48. As depicted in Figure 2, a frame consists of a header and a payload.
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`The payload is the actual data being communicated across the network and may
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`have an additional, internal structure as described below. The header contains,
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`among other things, a data link layer address of the computer generating the frame
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`(a “source address”) and a link layer address of the destination computer of the
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`frame (a “destination address”). The payload is analogous to a letter (“data”) that
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`is to be mailed to someone in an envelope (a “frame”), and the header is analogous
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`to the address written on the outside of the envelope. The link layer addresses in
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`the header of a frame are often referred to as “hardware addresses,” or “MAC”
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`(Media Access Control) addresses.
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`Figure 2: Illustration of the structure and major components of an Ethernet frame.
`(Not to scale)
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`49. Frames are variable-length structures with the size of a given frame
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`primarily determined by the size of the payload being transmitted. Frames have a
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`maximum size; payloads that are too large to be carried in a maximal size frame
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`must be segmented by the sender into multiple smaller payloads and transmitted in
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`a series of frames. This segmentation process is most commonly performed by
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`higher-layer network protocols as described below.
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`50. Layer-2 protocols can only transmit frames between two computers
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`on the same network. More precisely, layer-2 protocols can only transmit frames
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`between two computers on the same local-area network (“LAN”). In fact, the
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`technical definition of a LAN is the set of computers that are “reachable” from one
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`another (can communicate with one another) via a layer-2 protocol (and only a
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`layer-2 protocol).
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`51. LANs are created by a type of interconnection device called a bridge,
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`switch, or access point. Individual computers connect to the LAN
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`switch/bridge/access point via some physical medium such as, in the case of
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`Ethernet, the ubiquitous blue Ethernet cable. The typical interconnection device is
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`capable of interconnecting a large number of computers. When a computer
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`generates and transmits a layer-2 frame, the frame is received by the
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`interconnection device. The device examines the destination layer-2 address in the
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`frame to determine destination of the frame. Based on the layer-2 destination
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`address carried in the frame, the frame is forwarded to the appropriate destination.
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`“Forwarding” is a specific term in the networking arts and refers to the process that
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`is used by a layer-2 network interconnection device to transmit a frame to (or
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`towards) its ultimate destination.
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`52. LANs are limited in terms of both the number of computers that can
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`be on a LAN as well as the geographic area served by the LAN. The physical
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`media used to build the LAN and layer-1