Case 6:20-cv-00272-ADA Document 65-17 Filed 03/14/22 Page 1 of 4
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`Exhibit 15
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`Case 6:20-cv-00272-ADA Document 65-17 Filed 03/14/22 Page 2 of 4
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`RECEIVED LIBRARY
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`JUN 2 l 2010
`
`KIRKLAND & ELLIS LLP
`C HICAGO OFFICE
`
`Wireless
`Encyclopedia
`
`Eion Reference
`
`Published By:
`Althos Publishing
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`404 Wake Chapel Road
`Fuquay-Varina, NC 27526 USA
`Telephone: 1-800-227-9681
`1-919-557-2260
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`web: www.Althos.com
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`ALTHOS
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`Case 6:20-cv-00272-ADA Document 65-17 Filed 03/14/22 Page 3 of 4
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`Althos
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`All rights reserved. No part of this book may be reproduced or transmitted in any
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`the authors and publisher, except for the inclusion of brief quotations in a review.
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`Copyright © 2007 By Althos Publishing
`First Printing
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`Printed and Bound by Lightning Source Printing, La Vergne, TN USA
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`Every effort has been made to make this manual as complete and as
`accurate as possible. However, there may be mistakes both typographi(cid:173)
`cal and in content. Therefore, this text should be used only as a general
`guide and not as the ultimate source of information. Furthermore, this
`manual contains information on telecommunications accurate only up to
`the printing date. The purpose of this manual to educate. The authors
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`Case 6:20-cv-00272-ADA Document 65-17 Filed 03/14/22 Page 4 of 4
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`Gatekeeper Cluster
`
`'l'his figure shows how a gatekeeper sets up connec(cid:173)
`tions between Internet telephones and telephone
`gateways. The gatekeeper receives reb<istration
`messages from an Internet telephone when it is
`first connected to the Internet. This registration
`message indicates the current Internet address (IP
`address) of the Internet telephone. When the
`Internet telephone desires to make a call, it sends a
`message to the l'l'SP that includes the destination
`telephone number it wants to talk to. The I'l'SP
`reviews the destination telephone number with a
`list of authorized gateways. This list identifies to
`the !'!'SP one or more gateways that are located
`near the destination number and that can deliver
`the call . The l'l'SP sends a setup message to the
`gateway that includes the destination telephone
`number, the parameters of the call (bandwidth and
`type of speech compression), along with the current
`Internet address of the calling Internet telephone.
`'l'he gatekeeper then sends the address of the desti(cid:173)
`nation gateway to the calling Internet telephone.
`'!'he Internet telephone then can send packets
`directly to the gateway and the gateway initiates a
`local call to the destination telephone. If the desti(cid:173)
`nation telephone answers, two audio paths between
`the gateway and the Internet telephone are created.
`One for each direction and the call operates as a
`telephone call.
`
`Gatekeeper Cluster-A group of gatekeepers that
`are linked together (possibly using GUP)
`to
`increase the reliability of a system.
`Gatekeeper Update Protocol (GUP)-A proprj.
`etary protocol developed by Cisco to provide gate.
`keeper redundancy and load sharing. GUP can pro.
`vide information about a gatekeeper's memory
`CPU usage, number of endpoints that are regis'.
`tered, and available handwidth. GUP is based on
`TCP.
`Gateway-A gateway is a communications device or
`assembly that transforms data that is received from
`one network into a format that can be used by a di[.
`ferent network. A gateway usually has more intelli.
`gence (processing function) than a bridge as it can
`adjust the protocols and timing between two dis,
`similar computer systems or data networks. A gate(cid:173)
`way can also be a router when its key function is to
`switch data between network points.
`This figure shows how a gateway can convert large
`packets from a FDDI into very small packets in an
`ATM network. Not only does the gateway have to
`divide the packets, it must also convert the addresa(cid:173)
`es and control messages into formats that can be
`understood on both networks.
`
`Gateway Operation
`
`Voice Gatekeeper Operation
`
`Gateway D-Gateway Daemon
`Gateway GPRS Support Node (GGSN)-A pack(cid:173)
`et switching syst~m _that is used to connect a GSM
`mobile commumcat10n network (GPRS Support
`!lodes) to other packet networks such as the
`Internet.
`Gateway Location Protocol (GLP)-A protocol
`that was initially developed by a working group
`within the IETF to allow the gateway selection
`rocess in telephone and multimedia networks.
`~his protocol is now called telephony routing over
`Internet protocol (TRIP).
`Gateway Mobile Switching Center (GMSC)-A
`switching system that is used in a mobile commu(cid:173)
`nications network that also connects to other net(cid:173)
`works such as the public switched telephone net-
`• work (PS'l'N).
`Gating Pulse-A pulse that operates a logic gate.
`Gaussian Distribution-A statistical distribution
`that is used to represent occurences of specific
`events that follow a relatively even distribution
`around their center reference point. Gaussian dis(cid:173)
`tribution is a bell-shaped curve and it is also called
`a normal distribution. Also called white noise.
`Gaussian Frequency Shift Keying (GFSK)(cid:173)
`Gaussinn frequency shift keying is a form of fre(cid:173)
`quency modulation in which the modulating signal
`ahifts the output frequency between predetermined
`values to represent a digital signal and that infor(cid:173)
`mation signal (data) is passed through a Gaussian
`filter prior to modulation to minimize the rapid
`changes to the carrier signal. Typically, one fre(cid:173)
`quency shift is used to represent a digital one
`(lometimes called a mark) and the other frequency
`ihift represents a digital zero (sometimes called a
`!pace).
`Gauuian Minimum Shift Keying (GMSK)-A
`lirm of frequency modulation in which the modu(cid:173)
`lating signal shifts the output frequency between
`Pledetermined values. A form of MSK that uses
`llluaaian low pass filtering of the binary data to
`~IICe sideband energy.
`11.\z~P-General Audio Video Distribution Profile
`""8' ACHO-Generation, Alignment, Zero [sup(cid:173)
`ton], Polar, Alarm, Clock, Hunt, Office
`-
`,yte
`Busy Hour
`~~~n;,; Backbone Network
`. tgabits Per Second
`• -
`ate Controller
`
`General Packet Radio Service (GPRS)
`
`GCAC-Generic Connection Admission Control
`GCF-Gatekeeper Confirm
`GCIDs-Global Call Identifiers
`GCR-Group Call Register
`GCRA-Generic Cell Rate Algorithm
`GD-Graceful Discard
`GDDM-Graphical Data Display Manager
`GDF-Group Distribuiton Frame
`GDI-Graphics Device Interface
`GDMF-Generic Data Message Format
`GDOI-Group Domain of Interpretation
`GOOP-Geometric Dilution of Precision
`GDP-PI-GDP Price Index
`GOS-Global Directory Service
`GED-Global Engineering Documents
`Geek-A geek is a person who is focu sed on technol(cid:173)
`ogy, typically computers who does not tend to con(cid:173)
`form to mainstream habits such as dressing for suc(cid:173)
`cess and/or regular bathing.
`General Mobile Radio Service (GMRS)-General
`mobile radio service is a licensed FM radio service
`that operates at on channels in the 462 MHz and
`467 MHz UHF band.
`General Packet Radio Service (GPUS)-General
`packet radio service is a packet data communica(cid:173)
`tion system that uses the global system for mobile
`(GSM) radio system packet radio transmission. The
`GPRS system modifies the GSM channel allocation
`and time slot control processes to allow for the
`dynamic assignment of time slots to individual
`users. G PRS provides a maximum radio channel
`data transmission rate of 171.2 kbps.
`This figure shows some of the key GPRS network
`elements that include a gateway GPRS support
`node (GGSN), a serving GPRS support node (SGSN)
`and a GPRS backbone network (the Internet in this
`example.) This example shows that the GPRS sys(cid:173)
`tem adds dynamic time slot control to the standard
`GSM radio system. To provide packet data service,
`the GPRS system, the SGSN provides the processes
`of switching and access control that is similar to a
`mobile switching center (MSC) and a visitor loca(cid:173)
`tion register (VLR). However, the SGSN provides
`for switching and access control (authorization and
`tracking) based on packets of data rather than con(cid:173)
`tinuous connections. The SGSN registers and main(cid:173)
`tains a list of active packet data radios in its net(cid:173)
`work a nd coordinates the packet transfer between
`the mobile radios. The GGSN is a packet switching
`system that is used to connect a GSM mobile com(cid:173)
`munication network (GPRS Support Nodes) to
`other packet networks such as the Internet.
`
`256
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`EION Rcft•r·l'lll'l' - Win•ll-ss Encydopl'din
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`EION Rcferl'nec - Wireless Encyclopedia
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`257
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