Next Generation Networks - A Migration Path
`Digifonica Voice Over IP Technologies.
`
`Technology Overview
`
`DRAFT June 3, 2005.
`NOT FOR DISTRIBUTION
`
`Spring, 2005
`by Clay S Perreault, CEO / CTO
`Digifonica International Ltd
`Gibraltar.
`
`Next Generation Networks – Technology Overview • DRAFT • Digifonica • May 30, 2005
`
`Page 1
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`Voip-Pal Ex. 2020
`IPR2016-01201
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`

`

`Next Generation Networks - A Migration Path
`TABLE OF CONTENTS
`
`Section 1.0 – Digifonica Telephony Applications Framework
`1.1 Introduction
`1.2 Digifonica Global Telephony Platform Description and Vision
`1.3 Limitations in the Intelligent Networks Concept (INC) Model of the 1990's
`1.4 The Digifonica Global Telephony Platform
`1.5 The GTP Applications Framework
`
`Section 2.1 – Core Network Service Elements
`2.1.1 Core Design Parameters in the Digifonica Global Network:
`2.1.2 Digifonica Global Network Structure
`2.1.3 Digifonica Global Node Architecture:
`2.1.4 Core Network Implementation Processes
`2.1.5 Call Origination and Termination Processes
`2.1.6 Device Telephone Numbering in Digifonica Global Network
`2.1.7 ENUM concepts and use in the Digifonica global routing architecture
`2.1.8 CPE Device User Dialing Preferences and Digifonica DPRP
`2.1.9 Homeland Security Feature Set
`2.1.10 GTP Security Systems Implementations
`
`Section 2.2 – Network Applications Design and Provisioning Considerations
`2.2.1
`Service Portability with Respect to Use in Mobile Situations
`2.2.2 Number Portability
`2.2.3 Directory Services
`2.2.4 Mobile Dialing Methodologies
`
`Section 2.3 Special Network Applications and Provisioning Systems
`2.3.1
`Emergency Services Discussions
`2.3.2
`Emergency 911 Mapping , Enhanced 911 Services in Mobile Devices
`2.3.3
`Location Based Services and VoIP Device Roaming
`2.3.4
`TCP/IP Port Blocking by Network Operators
`2.3.5
`Security and Integrity in Mobile Devices using VoIP Technologies
`2.3.6 Voice Quality (QoS) Concerns
`2.3.7 Denial of Service (DoS) Internet Attacks and their affect on telephony services
`2.3.8 Virus Attacks and their effects on call Routing Systems
`2.3.9
`Firewall Traversal Technologies
`2.3.10 Redundancy & Resiliency in offering IP Telephony to mobile devices
`
`Section 2.4 CPE Applications and Provisioning Considerations
`2.4.1 Account Provisioning - Customer Maintenance Systems (CMS)
`2.4.2
`Initial and Upgrading of Client Side Software
`2.4.2
`Customer Premise Equipment (CPE)
`
`Section 2.5 Future Network Design Considerations
`2.5.1 IPV6 and its implications on the Digifonica Global Network
`2.5.2 Codecs and Compression Discussions
`2.5.3 Standards Compliance
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`Section 1 Next Generation Networks - A Migration Path
`
`1.1
`
`Introduction:
`
`VOIP Internet-based communications technology offers two major reasons for its popularity
`in recent years. The first is a significant reduction in service delivery cost to the consumer,
`the second is to offer a new suite of converged telecommunication products and services not
`possible with the existing (legacy) technologies in place today.
`
`In the category of cost reduction, VoIP has been touted as being able to significantly reduce
`the cost of service delivery up to 90% in comparison with legacy technologies. By selecting
`and employing the appropriate technologies and migration methods, local telephone
`companies (ILECs and CLECS), enterprise businesses, and long distance carriers are
`promised to reduce their operations costs to a fraction of what most currently endure in
`providing telephone services to their subscribers.
`
`In the category of new service delivery, VoIP technologies promise the potential of offering
`enhanced telephone services, such as voice mail, unified messaging, SMS messaging, video
`telephones, location based awareness, subscriber call control services, and real time rating
`and billing that are not offered by traditional telephone technologies today. These services
`are of course, not new, but the delivery of them over a single managed architecture utilizing a
`single common technology platform has never before been possible.
`
`In response to this need for delivery of these new services, Digifonica has created and begun
`execution of a strategy to deliver a technology platform designed for the provision of all of
`the technology required to deliver a full suite of converged telephone services over a TCP/IP
`based managed network. It has further expanded the technology platform development to
`include a globally managed network and telecom services support mechanism to create a
`seamless migration path for telecom companies of any size and any location on the globe to
`offer these new services in a rapid, scale able, secure and low risk manner.
`
`Building on Digifonica's strategy of creating a single managed global voice network and
`building the core services elements, engineering was also focused on client side software and
`hardware elements to ensure that services can be delivered in an ubiquitous manner across all
`communications devices. These software and hardware elements at the edge of the network
`were recently expanded to include the delivery mobile cellular telephony products and
`enterprise IP PBX services to its existing municipal IP Centrex services and
`residential/SOHO telephony products and service elements.
`
`The engineering team in Digifonica has been dedicated to the process of designing a global
`network and creating the appropriate technologies for almost a decade and is committed to
`continue to deliver the technology in the most cost effective and timely manner moving
`forward. This document was assembled to discuss the various technologies and techniques
`used in Digifonica's work on the resolution of as many of the current and anticipated
`requirements of delivering a comprehensive package of local telephone services over a single
`TCP/IP data network.
`
`Comments, questions and suggestions are welcome at the following address:
`techteam@digifonica.com.
`
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`Section 1 Next Generation Networks - A Migration Path
`
`1.2
`
`Digifonica Global Telephony Platform Description and Vision
`
`Digifonica’s development team has been designing and implementing new telecom solutions
`based on the latest versions of Voice Over IP protocols and specifically, a relatively new
`subset of these protocols, Session Initiation Protocol (SIP). The purpose of these efforts is to
`create a uniquely inexpensive yet massively scale-able on demand service provisioning
`system capable of providing a full suite of IP telephony services to existing telecom network
`operators globally.
`
`The vision for the delivery of a fully converged communications network is to provide all of
`the various components or elements necessary to offer basic telephone service to any location
`on the globe, and then expand this platform in a modular way to include delivery of new
`service not possible in the legacy systems deployed today. In the delivery of these new
`services it was recognized that for any existing telecom operator with legacy systems
`currently in place, they would need a seamless low cost, efficient migration path to minimize
`any risk in moving to the new technologies.
`
`The existing legacy systems have been under attack by many competitive forces and are now
`stretched very thin in their ability to morph further into delivering converged telephony
`solutions. Obvious stresses are beginning to appear in the old models when looking at the
`lack of solutions available for delivering combined fixed and mobile telephone and new
`converged telephone products such as Video within the existing model. Roaming from one
`mobile service operators network to another has been a continuous challenge to the industry
`and now it is further complicated by the emergence of WiFi Hot spot and WiMAX wireless
`products. Even the concept of roaming has now morphed to include traditional land line
`wired devices such as office telephones and is no longer limited to cellular telephone service.
`
`Competitive pressures and rapid technology advancements in wireless service delivery via
`Cellular and WiFi/WiMAX are leading to a massive swell in demand for new mobile
`services, but also provide significant opportunity for a carrier to to reinforce customer
`retention strategies and find considerable new sources of revenues from existing customer
`bases. Mobile Cellular Carriers for example have been actively diversifying their offerings to
`include value-added services such as “ring tones,” mobile gaming, and other services to
`increase their revenue base per subscriber(ARPU).
`
`In general, it has been very difficult to deploy a single ubiquitous wireless infrastructure that
`can sustain advanced services either from a technical or business-model point of view. The
`Digifonica global network and telecom service provision model was designed to
`accommodate all of the services that existing telecom operators may wish to offer to their
`subscribers while being fully compliant with their existing distribution platforms. This
`delivery platform promises an easily deployable, low risk, extensible method for deploying
`these new services by layering the new services over top of existing products.
`
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`In Summary:
`
`Digifonica's review of the telecommunications market place has found that in almost all of the
`existing telecom operators studied, irrespective of their geographical location or technology
`currently being used, the in place systems and business methodologies are facing significant
`challenges. The existing telecom operator is experiencing declining voice revenues, increased
`competition, increasing traffic patterns, paired with rapidly increasing demand for enhanced
`media-rich voice & data services. An off the shelf solution is not currently available from
`traditional suppliers of telecom hardware therefore it must be built.
`
`Digifonica has recognized this opportunity and has responded by creating the Digifonica
`Global Telephone Services Platform. Using this platform, we hope to resolve many of the
`specific service delivery and service consistency challenges associated with launching
`convergence telecom services while simultaneously supporting legacy services. The
`additional opportunity arising from the development of this global telephony platform is that
`it opens up a whole new generation of telecom operators that could never before exist due to
`cost and complexity. The Digifonica solution will be rapidly deployed in a manner that
`would provide seamless, low cost, low risk and almost immediate revenue for any group
`wanting to enter the telecom industry.
`
`A corporate sales strategy is currently being refined within the Digifonica marketing group in
`order to address any business issues to the creation of business relationships with reseller
`partners globally and is covered in a separate document.
`
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`Section 1 Next Generation Networks - A Migration Path
`
`1.3
`
`Limitations in the Intelligent Networks Concept (INC) Model of the 1990's
`
`The first step towards a feature-rich telecom network was made in early 1990s with the
`introduction of the Intelligent Networks Concept. The key principle of Intelligent Network
`Concepts (INC) was to separate the call processing logic from service logic and assign it to
`Service Control Points. INC provided a number of key advantages to the telecom operator as
`services could be more rapidly deployed across a network of multi-vendor Switch platforms
`than developing and deploying the features within the Switch fabric itself. INC also
`provided a solution that continued to provide a “trusted gateway” concept to the switching
`layer which was of extreme importance to the telecom operator. These concepts were
`perceived as being robust, scale-able and built for a world that requires a “real time” high
`volume transaction capabilities.
`
`The problem with the INC model was that it was very limited in its ability to accommodate
`the rapid changes in the telecom landscape and thus became a transitional methodology
`instead of a new services model. The INC was recognized late in the decade as more suited
`for the complex, regulated, incumbent dominated and TDM-oriented telecom world but
`unable to accommodate new services that were revolutionizing the telecom landscape such as:
`
`• The advent of Globally available and widely used Internet services
`• Convergence of corporate IT and Telecom departments
`• Convergence of new telephone and data services on fixed & mobile networks
`• Establishment of TCP/IP technologies and other Telecom standards such as SIP
`and H.323 protocols
`• Global deregulation trends
`
`Thus the INC model was not prepared to deliver true value-added services in this new
`environment that is becoming increasingly heterogeneous and competitive. In this context,
`INC posed some serious disadvantages – namely it did not lead to truly open systems inter
`operability:
`
`•
`
`•
`
`INC lead to low service deployment velocity & expensive service creation.
`Technical complexity and specialized skill set requirements resulted in low
`developer availability and high costs to the telecom operator.
`• No standardized, secure access was available to network resources from outside
`the internal Telco domain.
`INC only supported carrier hosted services. A secure, standardized integration
`with enterprise applications was not available. Hence enterprise applications were
`not able to leverage full capabilities of the telecom network.
`• Proprietary twists to INC caused vendor lock, limit portability and prohibitively
`high cost to change or develop new applications.
`INC only supported non-circuit voice services. Multimedia and Packet based
`Services were not part of INC scope.
`
`•
`
`There have been many limited attempts to open up the network using proprietary gateways at
`
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`both carrier and enterprise ends. Since the interfaces were proprietary in nature, this led to
`very limited enterprise applications (mainly messaging SMS and SS7 messages) traversing
`the networks.
`
`The bottom line is that the Intelligent Network is anachronistic to a modern modular solution
`design. A much better solution would be to create a parallel network and applicable service
`elements around service infrastructure modules such as Location Servers, Messaging Servers,
`and Voice Switches. This would neatly centralize the crucial function of security and
`authentication in an independent framework that would easily interface with all existing and
`more importantly, new applications and service entities as they emerge.
`
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`Section 1 Next Generation Networks - A Migration Path
`
`1.4
`
`The Digifonica Global Telephony Platform (GTP)
`
`The Digifonica Global Telephony Platform (GTP) takes all of the positive features of the
`Intelligent Network Concept described in the previous section, then expands it significantly to
`provide a much more flexible and rapidly deployable services model that encompasses:
`
`• Full and Seamless Integration with existing PSTN telephone services
`• Compliant with all telecom regulatory bodies
`• Compliant with all legacy PSTN equipment
`• Compliant with all VoIP technology standards
`• Operational as LOCAL dial tone in every country of the World
`• Resistant to typical Internet service disruptions
`• Scaleable on demand architecture with inexpensive to deploy initial services
`• Secure against viral or malicious attack
`100% fully hosted self contained services model
`•
`• Global roaming with presence management ability
`• SMS/MMS text messaging integration into the computer world's CHAT
`messaging technologies.
`• Development of new and enhanced services to desktop phones, video telephones
`and cellular applications.
`
`The GTP provides benefits for Digifonica's telecom partners in that it passes on to the
`Telecom Network Operator key control points in service delivery. It provides an independent
`100% open, standards based framework that ensures that operators have a truly multi vendor
`service and network infrastructure that is expandable and compliant with existing and new
`technologies as they emerge.
`
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`Section 1 Next Generation Networks - A Migration Path
`
`1.5
`
`GTP Applications Framework
`
`The GTP solutions Framework described in this document forms the basis of providing a full
`suite of services to the telephone subscriber while providing numerous opportunities for new
`revenue generation and customer retention to a telecom services operator.
`
`The Digifonica GTP provides is a set of core network components that conform to specific
`layer 3 and 4 network protocols and standards which enable translation and mediation of
`various multimedia telecommunications traffic types.
`
`Of note here is that the GTP resides in the Application Layers for providing telephone
`solutions over data networks. It does not provide nor demand any specific layer 2/3
`technology implementation thus creating a flexible implementation process to the network
`operator. Networks utilizing TCP/IP MPLS and DiffServ QoS parameters increase flexibility
`and quality of the overall implementation but are not necessary nor impediments if not
`present in the network. Typical Layer 2/3 networks would be ADSL, Wifi/WiMAX, Cable
`Modem HFC networks and fibre optic networks, but could also include GSM, 3G, or even
`dial up Internet / data services.
`
`The Digifonica GTP provides a set of core network components that can be broken down
`into three element segments:
`
`Service Mediation Elements:
`In this group, the DMAF components are the same elements available in the other Digifonica
`Digital dial tone services but also have specific extensions for multimedia converged
`applications. These elements are typically:
`
`• Call Control Components (SIP Messaging and Database Access methods)
`• NAT and Firewall Traversal engines
`• AAA (authentication, authorization, and Accounting)
`• RTP Proxy Services
`Internal Security Services Processes
`•
`• QoS (Quality of Service) Element Management
`
`Multimedia and Consumer Applications Elements:
`These are then enhanced by the addition of new components not typically found in traditional
`fixed telephone service delivery such as:
`
`• Location Based Awareness
`• Active Presence Awareness
`• Availability Elements
`• Converged Services Elements
`• On line Customer Self Care Services
`eBusiness & eCommerce functions
`•
`• Real time Billing Services
`• Help Desk and Trouble Ticketing Services
`
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`Section 1: Next Generation Networks - A Migration Path
`
`Mobile Applications Elements:
`
`Within the global digital dial tone GTP framework, a subset of this highlights special services
`requirements in relation to the mobility of IP endpoints and respective application sets. This
`subset is called the Digital Mobile Applications Framework or DMAF. The specific
`applications are generally the “User Facing” interfaces that a typical mobile subscriber would
`use to access the new digital dial tone services provided by the network operator using
`Digifonica's global telecom systems.
`
`The DMAF Framework provides the crucial functions of call control, security,
`authentication and gate keeping, which ensures only authorized applications and services are
`allowed to be a part of operators’ ecosystem. Since operators have been wary of opening up
`their networks due to security reasons, the Framework also addresses that critical issue while
`also providing the flexibility of services and service capability functions to be delivered in a
`manner in line with the business case & deployment requirements of the mobile
`telecommunications operator.
`
`Examples of these applications would be:
`
`• Cellular Telephone Dialer Application that interfaces with core TCP/IP Internet
`networks instead of the traditional Telco side of a GPRS or 3G network. These
`new applications would require the device to have a next generation operating
`system such as Symbian, Windows Mobile or Palm.
`• SMS and MMS Applications that interface with computer based chatting services
`such as AOL, MSN, and Yahoo.
`• User mobility and Call Control Applications such as Presence Management
`Applications and user managed Call Control service Management. Support for
`presence and availability features provides users with the convenience of access to
`another user’s presence before initiating any communication as well as allowing a
`user to control their own availability status.
`• Push-to-Talk Services where The mobile application Client supports one-to one
`and one-to-many PTT, Manual/Auto Answer and Do Not Disturb functions.
`• On-line Gaming Applications and their convergence with other messaging
`elements such as text messaging and voice services
`• Down loadable ring tones, telephone wall paper and screen saver applications and
`their interfacing with other elements of mobile telecom services.
`• Note that the concept of download able ring tones could also be expanded to
`standard desktop phones.
`
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`Section 2 Core Network Service Elements
`
`2.1.1 Core Design Parameters in the Digifonica Global Network:
`
`In all cases the following core design parameters are referred to as necessary and important
`prior to implementing or testing a new service, technology network elements:
`• Low Cost Entry: The complete initial installation must be inexpensive to deploy and fully
`scalable as subscriber bases grow. This feature will give us significant competitive
`advantages over others in the market. This low cost entry point must apply to ALL
`hardware components used.
`• Cost Effective: It must be cost effective to accommodate the current market environment
`of dropping long distance prices and competitive markets throughout the world. Moving
`forward the telephone services market will get more and more competitive. Using the
`Digifonica design we ensure that a cost effective and competitive feature set can be
`offered.
`• Scaleable: The service offering must be scalable to manage a significant client base of
`250,000 to 500,000 subscribers per node, yet start at a minimum of 50,000 subscribers in a
`low cost entry point. It must be able to scale on demand without service interruption in
`reasonably short periods of time adequate to supply service under typically exponential
`growth patterns exhibited in the cellular industry over the past 15 years.
`• Efficient: The system must use high compression in order to use low bandwidth
`broadband, dial up and poor quality network environments while providing adequate voice
`quality and features. High compression of RTP streams also enables further cost savings
`on the server side as well as reduces the number of computers necessary in a server rack.
`• Reliable: It must be carrier grade to give 99.999% uptime to provide adequate reliability.
`This mechanism must also distribute its databases in order to provide redundancy and
`resiliancy. Reliability comes at a cost. Variables in providing fully reliable and redundant
`services must be scaled according to network growth and subscriber expectations. These
`must be defined and well understood as the network is deployed.
`• Compliant: The Digifonica design must comply with ALL established standards in
`TCP/IP Networks, VoIP hardware and software and existing legacy PSTN technology. It
`must also accommodate ALL regulatory frameworks and incorporate expected transitions
`of regulatory issues from the PSTN to VoIP. IEEE RFC's and other industry groups
`establishing standardization of the industry must be adhered to strictly. Participation in
`the formation of the standardization schemas is also expected.
`• Quality: Voice quality must be as good or better than the existing telephone systems, the
`billing systems, feature sets and implementation must be equal or better than traditional
`systems.
`• Secure: It must be secure from hacking, viruses and malicious attack. This includes denial
`of service attacks, syn floods, worms, or malicious attempts to shut services down from
`hackers. The system must also incorporate security from a client perspective in order to
`ensure that if the subscriber signs up he is no less secure with our system running behind
`his firewall than before.
`• Sale able: It must be manageable within the ASP partner business model chosen by
`Digifonica and be flexible enough to accommodate new models as they occur.
`
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`Section 2 Core Network Service Elements
`
`2.1.2 Digifonica Global Network Structure:
`
`Based on the parameters of system design in the previous section, the following summaries are further
`created in order to architect and implement the systems as required.
`
`• User management/billing should take place centrally in the core of the network and should
`not be specific to any edge device. This will accommodate best practices for edge device
`scaling and redundancy. Being in the core, security can be enforced and the number of
`machines involved in the global network is limited to a few. Additional benefits involve
`the global aspects of call routing and management from multiple locations around the
`world operating as a single service to our customers.
`• Server technology should be something other than the current Microsoft offering as
`windows based platforms are too much of a security risk from hackers, and viruses.
`Licensing issues, upgrade ability, and reliable clustering technologies are also lacking
`from this software platform. Based on this criteria, the UNIX and Linux Operating
`systems and their derivatives have been selected as a platform of choice. More
`specifically, BSD UNIX has been chosen due to its stability and security.
`• Software licensing practices of existing solutions in the VOIP sector prohibit low entry
`cost and perhaps even low cost services over the long term thus the requirement to
`eliminate any and all software licensing on a per seat basis from the Digifonica model. In
`house designed software gives us the license free solutions we require and limit our
`immediate need for development of core systems from scratch.
`• Compliance with Industry standard computer hardware must be a core implementation
`consideration to keep costs low and ensure continued scaling as computing platforms
`evolve. Close attention is paid to any device or platform that may involve a reliance on a
`particular vendor or closed technology owned by another group. This is a rapidly evolving
`technology sphere thus all components of the systems are built in a modular fashion in
`order to “remove” one technology and “insert” another as things progress.
`• Redundancy and Resiliency is mandatory at every level. Each component must not create
`a single point of failure thus is either part of a load balanced cluster or a parallel standby
`cluster. Cluster routing and control systems are created at the Cisco Router level internally
`and through DNS systems externally.
`
`Through these methodologies, no single component failure nor even a full node failure should
`disrupt services for longer than a few seconds.
`
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`Section 2 Core Network Service Elements
`
`2.1.3 Digifonica Global Node Architecture:
`
`Digifonica designed the network architecture to accommodate scalability, load spikes and
`fail-over redundancy. The network can be scaled for regional demand increases by adding
`computing hardware into our points of presence. Geographic demand shifts are
`accommodated by replicating these access points globally as necessary depending on the load
`of the system and quality of data services in each area.
`
`The Digifonica network architecture is designed around the deployment of "Super Nodes" and
`"Mini Nodes" that serve as global route points. The “Super Nodes”, or Typical Continental
`Operations Centres, route traffic between continents and are placed directly on top of major
`fiber optic transmission points around the world and connect to multiple first class voice and
`data carriers. These Super Nodes also contain fully replicated accounting and authentication
`data plus additional applications.
`
`The “Mini Nodes”, or typical Regional Operations Centres, perform country or regional
`amalgamation of voice traffic, and act as voice/data proxy points to collect and redirect voice
`traffic from the regions of our network directly into our Super Node network. These Mini
`Nodes perform regional IP PBX features, handle direct communication with the CPE gateway
`equipment, perform the actual authentication / CDR collection services as well as working
`closely with the Super Nodes above them. Geographical expansion is deployed according to
`anticipated traffic patterns and best route analysis.
`
`“Hybrid Nodes” have also been conceptualized in order to provide technology assistance to
`congestion choke points, or provide for customers wishing to “own” specific parts of the
`network.
`
`REF: Global_Network_Architecture.sxw
`
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`Section 2 Core Network Service Elements
`
`2.1.4 Core Network Implementation Processes
`
`Digifonica Core Network design and selection processes include the requirement to co-locate
`the telephony application servers within Network Nodes and connected to the public Internet.
`These co-located nodes are placed in Tier 1 facilities at specific global locations in order to
`maximize route traffic efficiency and provide reliable service levels to subscribers.
`
`Additional nodes will be added to the network according to the Digifonica global expansion
`processes and as required to ensure reliable efficient calling.
`
`REF: Global_Network_Architecture.sxw
`
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`Section 2: Core Network Service Elements
`
`2.1.5 Call Origination and Termination Processes
`
`The Digifonica Global Services Framework depends on the standard set of global routing
`methodologies as standard desktop VoIP based service delivery. These methodologies apply
`for both inbound (origination) and outbound (termination) to the PSTN if applicable. Thus, if
`a call originates or terminates from or to the Public Switched Telephone Network (PSTN)
`with the Digifonica Global network, it must pass through a conversion process from Digital to
`Analog or vice versa.
`
`Digifonica maintains both its own VoIP gateways globally and in addition, multiplies our
`global presence with numerous carriers around the world. The company maintains strict
`adherence to all VoIP protocols such as SIP and H.323 and utilizes off the shelf Codecs such
`as G.711, G.723, G.729, GSM, and T.38 fax. By maintaining these baseline standards,
`interconnection issues with other carriers do not typically arise between our network and the
`PSTN.
`
`In order to reduce any possibility of failure with these gateways which could result in
`potential disconnection with the PSTN and our network, the Digifonica Global Routing
`systems maintain an active list of preferred carriers, gateway addresses, QoS parameters and
`pricing per minute for every city in the World. These multiple vendors for termination and
`origination also provide an extra layer of insulation from events such as regulatory changes,
`or geopolitical events interrupting core telephone services.
`
`Call Routing both incoming and outgoing are cores services within the Digifonica network.
`Experience has shown that flexibility on how we handle the routing of these calls is necessary
`due to our sales model. Examples of this that some of the sales partners that are already
`licensed carriers t