`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`
`LG ELECTRONICS, INC., TOSHIBA
`CORPORATION, AND VIZIO, INC.
`Petitioners
`
`V.
`
`STRAIGHT PATH IP GROUP, INC.
`Patent Owner
`
`INTER PARTES REVIEW OF U.S. PATENT NO. 6,108,704
`Case IPR No.: To Be Assigned
`
`PETITION FOR INTER PARTES REVIEW OF U.S. PATENT NO. 6,108,704
`
`UNDER 35 U.S.C. §§ 311-19 AND 37 CFR. § 42.100 et seq.
`
`DECLARATION OF HENRY HOUH, PH.D.
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`Page 1 of 67
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`LG Electronics Exhibit 1004
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`Page 1 of 67
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`LG Electronics Exhibit 1004
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`
`
`Table of Contents
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`Page
`
`I.
`
`I].
`
`INTRODUCTION .................................................................................. .. 1
`
`BACKGROUND AND QUALIFlCATlONS.....
`
`I
`
`III. MATERIALS CONSIDERED ............................................................... .. 5
`
`IV.
`
`PERSON OF ORDINARY SKILL IN THE ART ................................. .. 7
`
`V.
`
`BACKGROUND OF TECHNOLOGY .............................. ..
`
`.
`
`.
`
`.
`
`.
`
`.
`
`.
`
`.
`
`,
`
`.
`
`. .
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`_ .. 7
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`A.
`
`B.
`
`C.
`
`D.
`
`E.
`
`Static and Dynamic IP Address Assignment ............................ .. I3
`
`Name Resolution and Name-to-Address Mapping .................... .. 16
`
`Locating Devices with Dynamically Assigned Network
`Addresses .................................................................................... .. I8
`
`Common Network Protocols ..................................................... .. 22
`
`The Design of Network Communication Software Applications 23
`
`VI.
`
`SUMMARY OF THE ’704 PATENT .................................................. .. 27
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`VII. CLAIM CONSTRUCTION ............................................................
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`32
`
`A.
`
`B.
`
`C.
`
`D.
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`“point-to-point communication link” ......................................... .. 33
`
`“transmitting to the server a network protocol address received
`by the first process following connection to the computer
`network” (claim 1) ...................................................................... .. 34
`
`“network protocol address” ........................................................ .. 35
`
`“connected to the computer network” (claim I) / “on—line
`status” (claims I I and 22) .......................................................... .. 36
`
`VIII. OPINIONS CONCERNING THE MICROSOFT MANUAL IN
`VIEW OF NETBIOS......................_....
`.
`.
`.
`
`IX. OPINIONS CONCERNINGS THE MICROSOFT MANUAL,
`NETBIOS,AND PALMER
`..
`
`44
`
`X.
`
`OPINIONS CONCERNING THE MICROSOFT MANUAL,
`NETBIOS, PALMER, AND PINARD ................................................ .. 48
`
`XI- OPINIONS CONCERNING THE MICROSOFT MANUAL,
`NETBIOS, PALMER, PINARD, AND U.S. PATENT NO. 5,341,477 51
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`Page 2 of 67
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`1," Henry Houh, Ph.D., being of legal age, hereby declare, affimi, and state the
`
`following:
`
`I.
`
`INTRODUCTION
`
`1.
`
`The facts set forth below are known to me personally and I have first-
`
`hand knowledge of them.
`
`2.
`
`Other than paragraph 3, this declaration in support of a Petition for
`
`1merPar1‘es Review of U.S. Patent No. 6,108,704 is identical to my declaration of
`
`August 22, 2014, submitted as Exhibit 1004 in lPR20l4-01366.
`
`II.
`
`BACKGROUND AND QUALIFICATIONS
`
`3.
`
`I have been retained by counsel for LG Electronics, Inc., Toshiba
`
`Corporation, and VIZIO, Inc. (“Petitioner”) in order to submit this declaration in
`
`connection with Petitioner’s Petition for Imer Partes Review of claims 1, ll-12,
`
`I4, 16, 22-23, 27, and 30-31 ofU.S. Patent No. 6,108,704 (“the ’704 patent”). I am
`
`being compensated for my time at a rate of $590 per hour, plus actual expenses.
`
`My compensation is not dependent in any way upon the outcome of Petitioner’s
`
`Petition.
`
`4.
`
`My Curriculum Vitae is submitted herewith as Exhibit 1 to this
`
`declaration.
`
`5.
`
`I received a Ph.D. in Electrical Engineering and Computer Science from
`
`the Massachusetts Institute of Technology (MIT) in 1998. I also received a Master of
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`
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`Science degree in Electrical Engineering and Computer Science in 1991, a Bachelor
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`of Science Degree in Electrical Engineering and Computer Science in 1990, and a
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`Bachelor of Science Degree in Physics in 1989, all from MIT. During my time at
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`MIT, I took graduate-level courses in communications and networking.
`
`6.
`
`I defended and submitted my Ph.D. thesis, titled “Designing Networks
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`for Tomorrow’s Traffic,” in January 1998. As part of my thesis research, I analyzed
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`local-area and wide-area flows to show a more efficient method for routing packets
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`in a network, based on traffic patterns at the time. My thesis also addressed real-time
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`streamed audio and video.
`
`7.
`
`As further indicated in my CV, I have worked in the electrical
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`engineering and computer science fields, including in Voice over IP, on several
`
`occasions. As part of my doctoral research at MIT from l991-1998, I worked as a
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`research assistant in the Telemedia Network Systems (TNS) group at the Laboratory
`
`for Computer Science. The TNS group built a high speed gigabit network and
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`applications which ran over the network, such as remote audio and video capture,
`
`processing, segmentation and search on computer teiminals. In addition to helping
`
`design the core network components, designing and building the high speed links,
`
`and designing and writing the device drivers for the interface cards, I also set up the
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`group’s web server, which at the time was one of the first several hundred web
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`servers in existence and went on to provide what was likely one of the first live
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`Internet video initiated from a web site.
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`I co-authored papers on our web server
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`video system and on database-backed web sites for which I attended the first World
`
`Wide Web conference to present.
`
`8.
`
`I authored or co—authored at least twelve papers and conference
`
`presentations on our group’s research. I also co—edited the final report of the gigabit
`
`networking research effort with Professor David Tennenhouse and Senior Research
`
`Scientist David Clark. David Clark is generally considered to be one of the fathers of
`
`the Internet Protocol, and served as chief protocol architect for the Internet and
`
`headed the Internet Activities Board.
`
`9.
`
`From 1997 to 1999, I was a Senior Scientist and Engineer at NBX
`
`Corporation, a start-up that made business telephone systems that streamed
`
`packetized audio over data networks instead of using traditional phone lines. NBX
`
`was later acquired by 3Com Corporation, and to my knowledge the phone system is
`
`still available and being used at tens of thousands of businesses or more. As part of
`
`my work at NBX, I designed the core audio reconstruction algorithms for the
`
`telephones, as well as the packet transmission algorithms. I also designed and
`
`validated the core packet transport protocol used by the phone system. The protocol
`
`is used millions of times daily currently. Two of the company founders and I
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`received US Patent No. 6,697,963 titled “Telecommunication method for ensuring
`
`on-time delivery of packets containing time sensitive data,” for some of the work I
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`did there.
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`10.
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`After NBX, I worked at Teradyne, a test tool company primarily
`
`focused on semiconductors. Teradyne had recently acquired Hammer Technologies,
`
`a company that specialized in load and functional testing for telecommunications
`
`systems. The Hammer product line is well known as a telecom test tool, and
`
`Hammer products can be found in a large majority of telecommunications equipment
`
`and service companies’ test labs. Teradyne spun out Hammer and several other
`
`internal divisions into an independent company called Empirix.
`
`I became Chief
`
`Technologist of the Hammer division of Empirix. At Hammer, 1 conceived of, raised
`
`the internal funds for, and managed the team for launching the PacketSphere product,
`
`which included a network emulator intended for testing Voice over IP applications,
`
`among others. Companies purchased the Packetsphere to emulate an Internet
`
`Protocol network to see the effects of deploying their product on the Internet prior to
`
`launch. Packetsphere received several industry awards.
`
`11.
`
`Starting in 2001, I was architect for the next generation of web testing
`
`product by Empirix known as e-Test Suite. e-Test Suite is now owned by Oracle
`
`Corporation. e-Test provided functional and load testing for web sites. e-Test
`
`emulated a user's interaction with a web site and provided web developers with a
`
`method of creating various scripts and providing both functional testing (e.g., did the
`
`web site provide the correct response) and load testing (e.g., could the web site
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`handle 5000 users on its web site simultaneously). Among Empirix’s customers was
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`H&R Block, who used e—Test Suite to test the tax filing fiinctionality of their web site
`
`as whether the web site could handle a large expected load prior to the filing
`
`deadline.
`
`12.
`
`Around 2006, I helped create a search engine for audio and video which
`
`could be searched based on spoken word content. Our system used speech
`
`recognition and natural language processing to create a search index of audio and
`
`video files posted publicly on the Intemet. As VP of Operations and Technology of
`
`the spin-out company, I helped build-out a video hosting site where we provided
`
`hosted search and video serving services for our clients. Today, at the company now
`
`known as RAMP Inc., the project has grown to a product that is used by media
`
`outlets such as ABC, CBS, NBC, Fox, ESPN, and Reuters.
`
`13.
`
`I am the author of several publications devoted to a wide variety of
`
`technologies in the fields of electrical engineering and computer science. These
`
`publications are listed on my CV, included as Exhibit 1 to this declaration.
`
`14,
`
`I am familiar with the subject matter ofthis case and I consider myself
`
`an expert in telecommunications networks, data networks, and network protocols.
`
`III. MATERIALS CONSIDERED
`
`15. My opinions are based on my education, research, experience, and
`
`investigation and review of relevant materials.
`
`In forming my opinions, I have
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`considered the materials referred to herein, including:
`
`0
`
`0
`
`0
`
`-
`
`a
`
`0
`
`-
`
`I
`
`0
`
`0
`
`0
`
`0
`
`0
`
`I
`
`U.S. Patent No. 6,l08,704 (the “’704 patent”).
`
`File history for the ’704 patent.
`
`Reexamination history for the"704 patent.
`
`Microsoft Windows NT Server Version 3.5 TCPlP.HLP (the “Microsoft
`
`Manual”).
`
`Technical Standard: Protocols for )(/Open PC lnterworking: SMB, Version
`
`2.
`
`Protocol Standard for a NetBl0S Service on a TCP/U DP Transport: Concept
`
`and Methods, RFC i001 (Mar. 1987).
`
`Protocol Standard for a NetBIOS Service on a TCP/UDP Transport: Detailed
`
`Specifications, RFC 1002 (Mar. 1987).
`
`US. Patent No. 5,375,068 (“Palmer”).
`
`U.S. Patent No. 5,533,l 10 to Pinard et al.(‘.‘Pinard”).
`
`Dynamic Host Configuration Protocol, RFC 1541 (Oct. 1993).
`
`Transmission Control Protocol, RFC 793 (Sept. l98l)
`
`Intemet Protocol, RFC 791 (Sept. 1981).
`
`Comer, D.E., “Intemetworking with TCP/IP, Vol. l, Principles, Protocol, and
`
`Architecture, Second Edition,” (New Jersey: Prentice Hall, 1991).
`
`U.S. Patent No. 5,341,477 (the “’477 patent”).
`
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`IV.
`
`PERSON OF ORDINARY SKILL IN THE ART
`
`I6.
`
`I understand that the pertinent time for assessing the level of skill in
`
`the art is the earliest time of the filing of an application supporting the claimed
`
`inventions.
`
`I understand that a person of ordinary skill in the art is a hypothetical
`
`person who is aware of all reievant prior art.
`
`I understand that a person of ordinary
`
`skill in the art is a person of ordinary creativity.
`
`I have applied this standard
`
`throughout my declaration.
`
`17.
`
`The filing date of the ’704 patent is September 25, 1995. For
`
`purposes of defining a person of ordinary skili in the art, I will use September 25,
`
`1995.
`
`18.
`
`In my opinion, a person ofordinary skill in the art at the time ofthe
`
`filing of the ’704 patent would have a bachelor’s degree in computer science,
`
`computer engineering, or a related degree, and several years of experience in
`
`telecommunications and data networking. This person would have been capable of
`
`understanding and applying the prior art references discussed herein.
`
`19.
`
`At the time of the filing of the ’704 patent, I was at least one of
`
`ordinary skill in the art. My opinions set forth herein are from the perspective ofa
`
`person ofordinary skill in the art, as set forth above.
`
`V.
`
`BACKGROUND OF TECHNOLOGY
`
`20.
`
`A computer network enables computers to communicate with each
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`other. Most networks operate in accordance with protocols that specify how one
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`device communicates with another device. Supporting such point—to—point
`
`communication requires a mechanism by which a device sending a message can
`
`indicate which device or devices are to receive the message. For this purpose, most
`
`wide1y—used networks operate according to protocols that support addressing
`
`destination devices. Each device may have an address which, when included in a
`
`message as a destination address, indicates that the message is to preferentially go
`
`to that device. Most network protocols also specify a source address to indicate
`
`from which device data originated.
`
`21.
`
`In order to scale networks to the size of today’s Internet, smaller
`
`networks are interconnected to form large networks. The interconnection points
`
`between Internet Protocol (IP) networks areiknown as routers or gateways. The
`
`Internet Protocol is used at the network layer, and the routers and gateways
`
`determine the next forwarding path for each IP packet received, to determine
`
`which outbound link is best used to send the IP packet towards its destination
`
`address. Local Area Networks (LANS) such as Ethemets may be connected to
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`routers and gateways, and an IP packet may be delivered to its destination host
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`computer in such a LAN. For example, a gateway is part of many home networks
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`and is often provided by an Internet service provider. There may be many devices
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`attached to the home LAN, including computers, tables, and phones utilizing Wi-Fi
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`mode.
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`22.
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`Data sent according to modern network protocols typically contain a
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`header portion and a data portion. The header typically contains the source and
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`destination addresses for the data, and the data portion contains what is typically
`
`known as the payload. While any form ofdata containing a header and a payload
`
`is typically referred to as a “packet,” strictly speaking a “packet” is the protocol
`
`data unit at the network layer, such as the IP layer. An IP packet contains an IP
`
`header and IP data; the IP header contains the source IP address and the destination
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`IP address, amongst other data
`
`23. Within a home network, the protocol data unit used on the Ethernet
`
`LAN is known as a “frame." An Ethernet frame also contains source and
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`destination addresses, but the addresses used at the Ethernet layer are known as
`
`Media Access Control (MAC) addresses. Each Ethernet device is assigned a
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`unique ‘MAC address at the time of manufacture and is generally recognized as
`
`globally unique.‘ While devices on a LAN or Ethernet segment may communicate
`
`Eome Ethernet chips allow for the MAC address to be programmatically
`
`overwritten, and therefore mimic (or “spoof") another Ethernet device. This is not
`
`typical and thus Ethernet MAC addresses are considered to be globally unique.
`
`Each manufacturer ofa MAC device or chip is assigned one or more unique MAC
`
`prefixes, and the rest of the MAC address must be guaranteed by the manufacturer
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`with each other utilizing Ethemet-based protocols, most modern devices still
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`utilize IP protocols to communicate, even on a LAN or Ethernet segment.
`
`In this
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`case, the IP packet is contained entirely in the data portion ofthe Ethernet frame, in
`
`a process known as “encapsulation." In encapsulation, higher-layer protocols are
`
`encapsulated in the data portions oflower-layer protocol data units.
`
`24.
`
`For example, the Transmission Control Protocol (TCP) is often
`
`utilized “over" IP. The TCP protocol itself defines its own TCP header and TCP
`
`data portion. Each TCP “segment” containing a TCP header and TCP data is
`
`encapsulated within an IP packet, which when transmitted to a host on a LAN or
`
`Ethernet segment, is further encapsulated within an Ethernet frame.
`
`25- When data is received by a host computer, the data is processed from
`
`lower-layer to higher layer, first processing and removing the lowest layer header
`
`and passing the data contained within to the next higher layer protocol for
`
`processing. Most headers further contain an indication of the protocol utilized by
`
`the data contained within. For example, an Ethernet header has a two—byte
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`“EtherType” field, for which a value of“0x0800” indicates that the data within
`
`utilizes IPv4. An IP header contains a one byte “Protocol” field, for which a value
`
`of “6” indicates TCP and a value of “l 7” indicates the User Datagram Protocol
`
`(UDP), for example. The term “TCP/IP” is used to indicate that TCP segments are
`
`to be unique within the space of its MAC prefix for each device it manufactures.
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`10
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`encapsulated within IP packets, so that the data may be transported by IP networks
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`such as the Internet.
`
`26.
`
`Applications may use the layered protocol stack for transmitting data
`
`between applications running on networked computers. For example, “Voice over
`
`IP” often refers to the capability of IP to carry voice data and thus transmit the data
`
`over an IP network such as the lntemet. However, other protocols often carry the
`
`actual voice data, such as RTP/UDP/IP, in which case voice data is encapsulated
`
`within RTP, which is encapsulated within UDP, which is further encapsulated
`
`within IP, for example.
`
`27. Within IP routers, forwarding decisions for individual packets are
`
`typically made based on groups of consecutive IP addresses rather than individual
`
`IP addresses. The reason is that IP addresses are typically assigned and delegated
`
`in consecutive blocks and therefore often share physical locality. Network
`
`operators, such as Internet Service Providers and large enterprises, may only utilize
`
`and assign to its hosts public IP addresses from its designated and allocated address
`
`space?
`
`2 Internally, non-public IP addresses may be used. Public IP addresses are globally
`
`routable, but IP addresses assigned according to RFC 1918 “Address Allocation
`
`for Private Internets” published in February 1996 allows organizations to use
`
`certain blocks of IP addresses internally.
`
`l-lostnames may be mapped to these
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`28.
`
`IPv4 addresses have the form offour bytes, with each byte
`
`representing a number from 0 to 255, and are often written in the form offour
`
`numbers delimited with a dot, written consecutively, such as “74.l25.225.l7”.
`
`29.
`
`As ofthe filing date ofthe ’704 patent, traffic on the Internet utilized
`
`the Internet Protocol version 4 (“lPv4” or simply “IP”) to identify devices. This
`
`protocol was developed in the l970s and 19803, leading to the “Intemet Protocol
`
`Suite" standard in 1982, which formed the basis of the modern Internet and was
`
`also used in other computer networks- Historically, aspects of network
`
`communication have been standardized by the Internet Engineering Task Force
`
`(“IETF”), which codifies standards in documents called “Requests for Comments”
`
`or “RFCs” (the title of which is a historical artifact and is not to be taken literally,
`
`as these documents were widely distributed and used by engineers in designing
`
`networks and network products). The Internet Protocol was defined in RFC 791, A
`
`which was published in September 1981.
`
`
`
`“private” IP addresses, and furthermore the same addresses may be used by other
`
`‘organizations in their internal networks. However any name resolution based on
`
`such private IP addresses are strictly in the name space of the specific organization
`
`and are not global. These specially allocated blocks of IP addresses are atso not
`
`routable in the public Internet.
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`12
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`A.
`
`Static and Dynamic IP Address Assignment
`
`30.
`
`Typical network configuration for a host connected to an IP network
`
`requires that a host know at least two values related to IP: its own IP address and
`
`its subnetwork mask. An IP subnetwork is local IP network where hosts may
`
`communicate with each other on a LAN or Ethemet segment, and where all hosts
`
`on said subnetwork are assigned IP addresses within a range of IP addresses
`
`defined by a subnetwork number (which is a host IP address bitwise ANDed with
`
`the subnetwork mask). 3
`
`31.
`
`In order to communicate with other hosts on a different IP
`
`subnetwork, a host further requires a gateway address, which is the IP address of a
`
`router or gateway that interconnects the devices on one subnetwork with devices
`
`on other subnetworks. Also, in order to resolve fully—qualified domain names or
`
`hostnames to IP addresses, a host also requires the IP address of a domain name
`
`server or other server that may resolve hostnames to IP addresses. This is further
`
`discussed below.
`
`32.
`
`For some time after IP was standardized, a host’s IP address,
`
`subnetwork mask, gateway IP address, and domain name server IP address, was
`
`manually configured on each lntemet host. Because this was a tedious process that
`
`3 Newer network technology known as Virtual LANS or VLANs allow for LAN
`
`segments to be logically defined rather than physically defined.
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`13
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`was also prone to error, for example, such as accidentally assigning the same IP
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`address to more than one host, methods were devised for hosts to request and
`
`receive this information over the network via data frames sent to a host’s LAN or
`
`Ethernet segment (which does not require an IP address to utilize). The Dynamic
`
`Host Configuration Protocol was published as IETF RFC 1531 in October 1993.
`
`(Ex. I013 at 1.) This protocol defined the method by which a host acquired
`
`information over the network from a DHCP server, and was initially utilized to
`
`provide at least a host’s IP address, gateway IP address, and subnet mask to a
`
`requesting host over a LAN or Ethernet segment. The method whereby a DHCP
`
`server selects which IP address to assign to the requesting host (from its allocated
`
`pool of IP addresses) depends on the implementation. A DHCP server may assign
`
`a specific host the same IP address each time based on a host’s name or MAC
`
`address (“static”), may assign any IP address from its pool to a host (“dynamic”),
`
`preferentially assign IP address to host that it had previously assigned, or some
`
`mixture of both, for example static assignment for a small set of specific hosts
`
`combined with dynamic or preferential for other hosts.
`
`33-
`
`I understand that the Microsoft Manual was published and Microsoft
`
`TCP/lP was publicly available no later than August 31, £994. The Microsoft
`
`Manual discloses that Microsoft TCP/IP supported automatic TCP/IP configuration
`
`through the DHCP service. Therefore, as of at least August 3 1, 1994, devices on a
`
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`14
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`
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`Microsoft Windows NT network could be assigned either static or dynamic
`
`network addresses. A device assigned a static network address retained that
`
`address each time it connected to the network. A device assigned a dynamic
`
`network address, on the other hand, received a potentially different network
`
`address each time it connected to the network.
`
`34.
`
`Prior to the filing date of the ’704 patent, most private home users
`
`connected to the Internet via an Internet Service Provider (“ISP”) via a dial-up
`
`modem. The ISP typically was allocated a block of IP addresses, and would
`
`dynamically assign one of the addresses from its pool to a subscriber's computer
`
`when the computer connected to the Internet. Because only a percentage of an
`
`ISP’s customers were expected to be dialed—in at the same time, an ISP would
`
`typically dynamically assign IP addresses to its customers, and would not have
`
`enough modems or public IP addresses for all its customers.
`
`In addition, in the
`
`1990’s, IPv4 address space was very inefficiently allocated to various
`
`organizations” and it was believed that the Internet was close to being out of IPv4
`
`addresses to allocate. Thus, the organization responsible for assigning public [P
`
`4 For example, organizations such as MIT, BEN, GE, IBM, Xerox, HP, DEC,
`
`Apple, Ford, CSC, AT&T, Eli Lilly, Prudential Securities, DuPont, Daimler AG,
`
`Merck, Bell Northern and the US Postal Service, among others, were allocated
`
`over 16 million IP addresses each, or l/256 the total number of IPv4 addresses.
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`15
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`address space became stingy with handing out very large blocks of IPv4 address
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`space due to an increasing number of requests and a rapidly declining amount of
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`unassigned space.
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`35. After the DHCP RFC was first published, and by the filing date ofthe
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`’704 patent, dynamic IP address assignment was well known as one of the methods
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`utilized by a DHCP server for address assignment to requesting hosts.
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`36.
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`In addition, as part ofthe DHCP protocol, a device leaving the
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`network may explicitly release its assigned network address back to the DHCP
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`server so that the server could re-assign that network address to another device
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`that laterjoined the computer network. An explicit release is not required, as an
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`address assignment is made for only a fixed lease period. However, a host must
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`renew its lease prior to its expiration in order to continue using its assigned IP
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`address. This allows the DHCP server to re—assign addresses that are not renewed
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`after the expiration of the lease period.
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`B.‘
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`Name Resolution and Name-to-Address Mapping
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`37.
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`IP addresses are numbers, as described above. For example, the IP
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`address for a website could be 100.100.200.20. Because these network addresses
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`are difficult to remember, there existed a need to link the addresses with more
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`easily remembered names. In addition, the use of a name-to-address mapping
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`system allows machines to be moved physically or services to be moved to
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`different machines, allowing for names to be redirected to different IP addresses.
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`One benefit ofthis additional redirection is that names may be given out and
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`printed on materials without fear that the name will change.
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`38.
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`A solution to the name-to-address problem was developed in the
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`context of computer networks as early as the 19805. One example is the Domain
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`Name System (DNS) (developed in the 19805) to translate IP addresses into
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`domain names. The DNS mapped domain names (e.g., ftpsymbolicscom, the first
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`.com domain registered in 1985)) to IP addresses (e.g., 100.100.200.20). As part
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`of a networked computer application (eg., ftp or telnet) making a connection to a
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`remote site, it would access a “DNS server” that, like a telephone book, mapped
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`domain names to IP addresses. A DNS server is transparent to a user and provides
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`a computer browser with the IP address of the requested domain name, thereby
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`allowing the browser to access the sewer hosting the website.
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`39. Microsoft implemented a similar name resolution solution in the context
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`of a local computer network. The manual for Microsoft TCP/IP for Windows NT 3 .5
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`(“the Microsoft Manual”) describes the “Windows Internet Name Service,” or WINS
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`(Ex. 1012), discussed below in further detail.
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`40.
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`The WINS technology allowed a user running Windows NT 3.5 to use
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`easily remembered names to access other computers or devices on a computer
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`network. For example, it was desirable to assign easily remembered names to
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`different printers available on a network (e.g., 3rd Floor Printer, 4th Floor Color
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`Printer), rather than requiring a user to remember an [P address to select a
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`particular printer connected to the network.
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`41. According to Microsoft, WINS “solve[d] the problems that occur with
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`name resolution in complex intemetworks” and provided a distributed database for
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`querying “computer name—to-IP address mappings in a routed network
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`environment.” (Ex. lOl2 at 65.) Like DNS, WINS was essentially a directory
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`assistance operator that provided a first device with the network address of a
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`second device based on a name associated with the second device.
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`C.
`
`Locating Devices with Dynamically Assigned Network Addresses
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`42.
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`As discussed above, dynamically assigning network addresses was
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`common prior to the filing date of the ’704 patent. There were several benefits to
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`dynamically assigning network addresses, many of which still apply today. Use of
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`dynamic addresses was and remains administratively simpler because client
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`devices could usually be provided with dynamically assigned addresses without
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`any action being taken on the part of the client device user. Static addresses, on
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`the other hand, required a user or network administrator to configure the device
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`with the appropriate static address and to keep track of the static addresses that
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`were already assigned to other devices on the network.
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`43.
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`In addition, dynamic addresses were provided to devices on the
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`basis of need, rather than by assignment ofa static address whose usage must be
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`allocated and tracked long tenn. This was particularly useful in the environment
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`ofthe 1990s in which [SP5 had millions ofdial-up modem customers, but only a
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`small fraction ofthem would be dialed in and need an IP address at any given
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`time.
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`44.
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`Today, this is particularly useful in mobile environments, since a
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`single device, e.g., a laptop computer, could connect to different networks over
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`time and could be given a dynamic address each time it connects to a network.
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`The address assigned by a particular network to the mobile device at one time
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`would be assigned to other devices that connect to that particular network at
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`other times. Use of such a mobile device with static addresses, on the other
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`hand, would be administratively burdensome for both users and network
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`administrators because a network may have an addressing scheme that is
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`inconsistent with the static address assigned to the device, or because the
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`network may already be using that address for another device connected to the
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`network. Furthermore, IPv4 addresses do not support mobility. Therefore, a
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`mobile device with a static address cannot be expected to smoothly connect to a
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`new network.
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`45. Dynamically assigning network addresses, however, also introduced a
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`further complication to the name-to-address mapping problem: how to accurately
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`map device names to network address that are constantly changing. This was akin
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`to a telephone system in which users received new telephone numbers each time
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`they hung—up the phone. While a caller can still make calls, it is difficult for other
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`callees to determine the caller’s new telephone number.
`
`46.
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`Solving this added complication required developing mechanisms that
`
`enabled devices, such as computers, to update a name resolution database as new
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`network addresses were assigned to devices on a computer network. The computer
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`network industry developed these mechanisms well prior to the filing date of the
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`’704 patent.
`
`47.
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`For example, WINS mapped dynamic network addresses to device
`
`names. As each device connected to the network, a DHCP server assigried it a
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`dynarnjc network address. (Ex. 1012 at 4, 11, 73-74.) The device then registered its
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`name and its dynamically assigned network address with the WINS directory
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`server. (Id. at 65-69.) WINS thus maintained a mapping of dynamically assigned
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`network addresses to device names that was updated each time a device connected
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`to the network (i.e., each time a device was assigned a new dynamic network
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`address).
`
`48. Given its use in a dynamic addressing environment, WINS needed to
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`update its database regularly, and included a technique for doing so. Each device
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`registered its name with the WINS server. Upon the device disconnecting from the
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`computer network, it would send a “release” message informing the server that the
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`name was no longer being used and the computer associated with the name was no
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`longer connected to the computer network. (Id) WINS would then update its
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`database to reflect the fact that the name was no longer registered. (Id.)
`
`49.
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`Because computers occasionally disconnected fiom the computer
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`network without properly shutting down, the release process was not perfect.
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`WINS therefore also required computers to periodically “renew” or re-register
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`their