Technical White Paper

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1 Technical White Paper GENESYS SOLUTIONS FOR NEXT-GENERATION NETWORKS Introduction Telecommunications companies globally are transforming their businesses and their networks by replacing legacy digital networks with IP-based Next-Generation Networks (NGN) and creating the framework to deliver advanced multimedia services. The impetus is to enable new types of services, reduce costs, generate new revenue streams, and to ensure service faster than ever before. Telcos are pursuing Fixed-Mobile Convergence (FMC) to create synergies between their fixed and wireless companies and wireless operators are also evolving the radio network from second generation (2G) to 3G, and a Nordic operator has already gone live with a 4G radio network. These changes also impact other areas of the business, such as customer service a key differentiator in many saturated markets with high mobile phone penetration rates or high levels of competition between multiple operators. One of the keys here is the evolution of the contact center infrastructure, which must also follow the path of the network changes without causing existing investment in applications to be affected. Genesys has taken note of this industry transformation among its customer base and is currently working in partnership with a number of operators to effect this transformation. Continuing the decades-old approach of being infrastructure-agnostic, Genesys already has had success in integrating equipment from network infrastructure vendors such as Ericsson, Nokia Siemens Networks, Huawei, and Alcatel-Lucent. This technical white paper provides background information regarding NGN variants and how Genesys interoperates with them. We also recognize that no network transformation occurs overnight, so we show how legacy networks can co-exist with NGNs, while connecting to the same set of Genesys applications.

2 Technical White Paper: Genesys Solutions For Next-Generation Networks page 2 Table of Contents Introduction...1 Legacy Networks...2 Standards Bodies...2 A Bit About NGNs...3 Technical Concepts...3 Intelligent Networks and SS7...3 SS7...3 SIGTRAN...4 NGN and SS7...4 BICC...4 SIP-I...4 SIP-T...4 Media Gateway Control: MGCP/H.248/MEGACO...4 Release 4 Networks...5 IP Multimedia Subsystem...5 IMS Entities...6 Multimedia Resource Function (MRF)...6 Interfaces...7 Where Genesys Fits in the NGN...8 SIP Server and GVP - Direct Network Connection...8 SIP Server and GVP - Network Connection via the Chameleon Server...9 SIP Server and GVP - Other Network Connection Possibilities...9 Conclusion...9 Appendix...10 List of Figures Figure 1: SS7 Protocol Stack...3 Figure 2: SCTP/M3UA Protocol Stack.4 Figure 3: BICC Protocol Stack...4 Figure 4: Architecture for a Release 4 Network...5 Figure 5: Architecture For IMS...6 Figure 6: Interfaces...7 Figure 7: Network Connection for SIP Server and GVP...8 Figure 8: Chameleon Server Signaling Connections...9 Legacy Networks Even as operators migrate to NGNs, the majority of their networks will still rely on their existing Intelligent Networks (IN). The IN got its start in number translation services in the US for number calls (freephone, toll free or green number, 0800 in Europe). These kinds of numbers cannot be routed in the PSTN, since they are not bound to a geographical location, and needed to be translated into numbers that could be routed and, in the end, result in a ringing phone or IVR announcement somewhere. The IN relies on SS7 (Signaling System number 7) for signaling, while using digital lines (E1s) for transmission of media. The signaling network is separate from the media transmission network, thus requiring the maintenance of two separate networks. Due to the influence of the IP world and the need to drive down CAPEX and OPEX, while maintaining interoperability with existing legacy networks and enabling the creation of new, revenue-generating services, different standards bodies began investigating ways to introduce new technologies that would still interoperate with the existing ones. Standards Bodies Before diving into NGNs, it is important to have some knowledge of the standards bodies that create and influence the new technologies. There are several standards bodies that are involved in work related to euro-centric NGNs, including the IETF, 3GPP, ETSI, and the ITU. The important standards bodies for CDMA2000-based systems are the 3GPP2 and TIA. The Internet Engineering Task Force (IETF) is responsible for Internet standards and publishes them in RFCs (Request For Comment). Well-known RFCs include RFC3261 for SIP and RFC3550 for RTP. The International Telecommunication Union Telecommunication standardization sector (ITU-T) is a United Nations body that provides global standards for telecommunications. It provides standards in a series of lettered documents, such as the G series for codecs (G.711) and Q series for SS7 (Q.701). The European Telecommunications Standards Institute (ETSI) is a recognized European Union standards body that was responsible for the GSM standards. It publishes Technical Specifications and Technical Recommendations that sometimes refer back to the ITU-T standards. The part of ETSI that deals with IMS is TISPAN (Telecommunications and Internet converged Services and Protocols for Advanced Networking). The Third Generation Partnership Project (3GPP) is an association of standards bodies in multiple countries or regions, including ETSI, tasked with evolving GSM specifications into 3G and beyond. Their specifications are provided as a series of releases, with the most popular ones in the field tending to be Release 4-7 networks. The Signaling Transport group (SIGTRAN), a joint group of the IETF and ITU-T, designed a set of protocols to provide a standard for carriage of SS7 over IP or ATM that provides the same level of resilience and ease of interworking as the existing implementations.

3 Technical White Paper: Genesys Solutions For Next-Generation Networks page 3 A Bit About NGNs The NGN from a 3GPP perspective initially applied to GSM operators, who have tended to be ahead of fixed-line carriers with respect to innovation. NGN concepts applied to both the core network as well as the radio access network. In the network core, operators started with Release 4 networks, which introduced an IP network into the core as an option. This IP-based core was expanded in Release 5 to become SIP-based, called the IP Multimedia Subsystem (IMS). The arrival of IMS also aroused interest by fixed-line carriers, thus leading to Fixed-Mobile Convergence of the core network. For wireless operators, the radio network is evolving from 2G to 3G and even beyond to Long Term Evolution (LTE), thus providing higher and higher data rates, which enables interesting high-bandwidth applications such as high-quality video. Technical Concepts In order to understand where Genesys solutions fit into Next-Generation Networks, some basic technical concepts need to be introduced. Intelligent Networks and SS7 The Intelligent Network has evolved from its origins of number translation in the fixed-line network into areas such as charging control and call control. It was then transported into the mobile world and optimized for that environment, which GSM is called CAMEL (Customized Applications for Mobile-Enhanced Logic). The nervous system of the IN is SS7. It is generally used in inter-switch signaling within Telco networks, but has found its way into other areas, such as Network IVRs and PBXs. It is at the heart of communications within GSM networks, including 2G and 3G networks, and will not disappear anytime soon. SS7 SS7 encompasses a set of protocols in a layered structure which deal with everything from connection management to application layer communications. There are international (ITU), national (e.g. ETSI), carrier-specific (e.g. France Telecom), and vendor-specific (e.g. Alcatel-Lucent) variations, as well as versions that are published periodically. Therefore, it is necessary to understand exactly what needs to be supported. > ISUP ISDN User Part: used to control the setting up and tearing down of trunks, charging, etc. > INAP Intelligent Network Application Part: used as the signaling protocol for the IN > CAP CAMEL Application Part: used as the signaling protocol for CAMEL > MAP Mobile Application Part: used as the signaling protocol for registering mobiles, providing location updates, etc. in GSM > USSD Unstructured Supplementary Services Data: used to transmit information between the mobile and a network in GSM. USSD is used to query or alter call forwarding information or trigger an application in the network, such as a callback application. ISUP The Telecommunications Industries Association (TIA) is a trade association representing information and communications technology industries which started in the USA. The Third Generation Partnership Project 2 (3GPP2) is an association of standards bodies in multiple countries or regions, including TIA, tasked with evolving ANSI-41/CDMA2000 specifications into 3G and beyond. 3GPP2 work on IMS has closely followed the work of 3GPP, thus leading to harmonization work that takes into account any specific variations due to radio access technologies. INAP/CAP/MAP/USSD MTP 1-3 TCAP SCCP Figure 1: SS7 protocol stack

4 Technical White Paper: Genesys Solutions For Next-Generation Networks page 4 SIGTRAN M3UA SCTP IP Figure 2: SCTP/ M3UA protocol stack Signaling Transport or SIGTRAN provides a set of protocols for interworking between the PSTN and IP networks for SS7 signaling transmission. It is also the name of the IETF Working Group which produces the specifications, whose framework is in RFC Depending on the level of SS7 information required between two nodes, different levels of interworking are needed. These different protocols require the use of SCTP as an analog of TCP or UDP, which do not suit the needs of SS7 signaling transport. Stream Control Transmission Protocol (SCTP) [RFC2960] is an end-to-end transport protocol that provides services which have the best of TCP, with some additions to make it useable for SS7 signaling. M3UA or MTP3 User Adaptation uses the services of SCTP to transport ISUP and SCCP messages and, as the name implies, is an analog to MTP3. A benefit of using SIGTRAN is that SS7 cards are not required to terminate standard SS7. Instead, standard Ethernet NICs can be used, since it is transported on IP. NGN AND SS7 In the Release 4 network, ISUP and a number of its variants are used to set up trunks to the mobile network switch and for call control. BICC M3UA SCTP IP Figure 3: BICC protocol stack BICC BICC is Bearer Independent Call Control, defined in ITU-T Q.1902 and ETSI TS , among others as BICC CS2. It is designed to transport ISUP messages over various protocols, including IP. BICC is normally used with SIGTRAN. The 3GPP adopted BICC CS2 in the Release 4 standard. BICC separates call control from control of the bearer connection, so that there is a function that handles call sessions, and another that handles media control, such as that used to control a Media Gateway. Within 3GPP, BICC was designed to only be used within a single operator s network, thus limiting its usefulness. SIP-I SIP-I is SIP with encapsulated ISUP and specified by the ITU-T in Q in order to describe the transport of ISUP messages via attachments to SIP messages. The 3GPP has adopted it in the Release 8 standards as one of the options in addition to BICC and ISUP. SIP-T SIP-T is SIP for Telephones and specified by the IETF in RFC 3372 in order to describe the transport of ISUP messages via attachments to SIP messages. Media Gateway Control: MGCP/H.248/MEGACO MGCP is the Media Gateway Control Protocol, which is used to control Media Gateways, whose purpose is to convert media streams between TDM and IP networks. An alternative to MGCP is H.248/Megaco, which essentially does the same thing. A Media Gateway Controller needs this protocol in order to ensure that the signaling and the voice (or other media) are properly associated when bridging the TDM and VoIP worlds. In Release 4+ networks, H.248 is specified as the control protocol.

5 Technical White Paper: Genesys Solutions For Next-Generation Networks page 5 Release 4 Networks The Release 4 network architecture introduced several innovations to the GSM network. The two points relevant to this discussion are the separation of the MSC into the MSC Server and a Media Gateway (MGW), and the introduction of an IP-based core network. Separating the MSC provides the benefit of allowing the signaling and media to evolve separately, thus enabling a more flexible architecture. Using an IP network for signaling has enabled BICC to become a more popular signaling protocol than ISUP. BICC enables attached equipment to interoperate with the MSC Servers MGW, rather than requiring an additional external MGW, as would be the case with an MSC. Multiple MSC Servers can control multiple Media Gateways, so there is the possibility to save on equipment. The Media Gateway also has flexibility in determining how it communicates with external networks or internal equipment, such as an IVR. Options include standard RTP or more complicated protocols such as Nb UP (Nb interface User Plane protocol, based on the Iu UP [Iu interface User Plane protocol]). As shown in Figure 4, the radio network connects on the signaling side to an MSC Server via the Iu interface and Iu Control Plane protocol. The MSC Servers communicate with each other and with the IVR over the Nc interface via BICC in this example. The MSC Servers control the Media Gateways via the Mc interface using the H.248 protocol. With respect to the media, the radio network uses the Iu User Plane protocol over the Iu interface to transmit it. The MGWs communicate with each other over the Nb interface using either standard RTP or the Nb User Plane protocol. The MGW also communicates with the IVR over the Nb interface using RTP only. Figure 4: Architecture for a Release 4 network MSC Server MSC Server lu UP/lu BICC/Nc BICC/Nc Radio Network H.248/Mc H.248/Mc IVR lu UP/lu RTP, Nb UP/Nb RTP/Nb Media Gateway Media Gateway IP Multimedia Subsystem Building on Release 4 s introduction of IP to the core network, Release 5 continued the evolution of the core network with the IP Multimedia System (IMS) based on SIP. Having SIP-based softswitches firmly embedded the concept of a unified telephony and Internet architecture. In addition, fixed line networks have seen the benefits, causing them more and more to adopt IMS in their current and future plans, enabling those in both the fixed and mobile businesses to move towards FMC.

6 Technical White Paper: Genesys Solutions For Next-Generation Networks page 6 The IMS connects to the mobile Radio Access Network as well as to external entities, such as the IN or PSTN. It contains entities which fulfill the roles of switching, IVR, security, policy control, identity verification, charging and so on, as in the normal mobile network. IMS Entities Though the IMS contains a large number of entities, only the few that are relevant to Genesys applications are mentioned. Genesys applications will not normally interact or connect directly with any of the other entities. > > CSCF the Call Session Control Function is the softswitch and handles call session control, policy enforcement, CDR generation, etc. In the case of Genesys applications, they connect to a specific type of CSCF called the Serving CSCF (S-CSCF) > > MRF the Multimedia Resource Function provides IVR-like functions > > HSS the Home Subscriber System is similar to the HLR in a mobile network, containing identity, Media Figure5: Architecture for IMS authentication subscription, and other profile information for the users > > AS the SIP Application Server provides the services available in the network or other information which can control call sessions > > ECF the Event Charging Function provides online charging capabilities for prepaid services > > CCF the Charging Collection Function provides offline charging capabilities for post-paid services Multimedia Resource Function (MRF) The part of the IMS tasked with IVR-like functions is the Multimedia Resource Function (MRF). It is designed to play announcements, perform transcoding and set up conferences, among many other functions. (In earlier NGNs, the MRF was simply a Media Resource Function that concentrated on voice.) It is composed of a Multimedia Resource Function Controller (MRFC) and a Multimedia Resource Function Processor (MRFP). The MRFC: SIP AS > > Controls the media stream resources in the MRFP IMS Network > > Interprets information coming from an AS and S CSCF (e.g. session identifier) and control MRFP accordingly > > Generates CDRs. HSS S-CSCF CCF ECF MRF

7 Technical White Paper: Genesys Solutions For Next-Generation Networks page 7 The MRFP: > > Controls bearers > > Provides resources to be controlled by the MRFC > > Mixes incoming media streams (e.g. for multiple parties) > > Sources media streams (for multimedia announcements) > > Processes media streams (e.g. audio transcoding, media analysis) > > Enables Floor Control (i.e. manages access rights to shared resources in a conferencing environment). Interfaces The main interfaces of interest (see Figure 6) are: > > Mr this interface between the S-CSCF and MRF is similar to the interface between a network switch and IVR or SSP and IP in the IN world. The Mr interface is not completely specified today, but allows a number of different signaling options based on SIP, including: NETANN (RFC 4240) MSCML (RFC 4722) MSML (RFC 5707) > > ISC the IMS Service Control interface enables a SIP AS to control a call session via the S-CSCF using SIP > > Sh this interface enables the SIP AS to download subscriber profile information in order to determine how the SIP AS handles a call. The SIP AS can also update profile information using the same interface > > Ro this online charging interfaces enable the SIP AS and MRF to retrieve credit information about a subscriber (typically a prepaid one) from the ECF and update that information when needed > > Rf this offline charging interfaces enable the SIP AS and MRF to provide CDRs about a call (typically a post-paid one) to the CCF > > The Sh, Ro, and Rf interfaces use the Diameter protocol. Figure 6: Interfaces Diameter/Sh HSS IMS Network SIP AS SIP/ISC S-CSCF SIP/Mr Diameter/Rf CCF Diameter/Rf MRF Diameter/Ro ECF Diameter/Ro Media

8 Technical White Paper: Genesys Solutions For Next-Generation Networks page 8 For the purposes of this discussion, the version of Genesys GVP is and the version of Genesys SIP Server is Where Genesys Fits In The NGN Within the context of the entities and interfaces described in the previous section, Genesys provides products that serve as a SIP AS and MRF. Conformance of these products to their respective interfaces is initially expected in the 3GPP Release 9.0 framework with the ALU Release 9 IMS core network in the 2011/2012 timeframe. In the meantime, Genesys works with a number of partners today to provide integrations to multiple flavors of VoIP, Release 4 and IMS networks (as well as IN), where the network core is from a variety of vendors, including ALU, Ericsson, NSN, Italtel, and Huawei. The SIP AS entity is provided by the Genesys SIP Server, with all other Genesys functionality (with the exception of media services) essentially being available via the SIP Server. The SIP Server can act as an Application Server by providing intelligent routing decisions for routing calls to agents registered in the network, as well as towards the MRF. In addition, it can also act as a PBX/ACD application with agents that are registered to itself and not to the network. The Genesys Voice Platform (GVP) fits within the IMS reference architecture as an MRFP, and also has elements of an MRFC. The GVP is able to execute VXML and CCXML (and SCXML in the future) documents in order to provide media services. It can interact with the SIP Server as well as with external Application Servers. SIP Sever and GVP Direct Network Connection The SIP Server acts as an Application Server today and supports a number of VoIP softswitches, such as the Siemens HiPath 8000 and BroadSoft BroadWorks. In these cases, the contact center agents register with the softswitches, but are managed by SIP Server. As an alternative, agents can register on SIP Server and SIP Server acts as a PBX/ACD when connected to softswitches such as the Alcatel-Lucent OmniPCX Enterprise and Sonus EMS/GMX/PSX. See Figure 7. Figure 7: Network connection for SIP Server and GVP Network Softswitch Genesys Applications SIP Server SIP AS Genesys Call Center Applications GVP Media The cases mentioned above are standard, certified VoIP integrations. It is also possible to integrate SIP Server directly via SIP Trunks with Release 4 MSC Servers and CSCFs in IMS networks, though this is done on a project basis to achieve certification. For GVP, the situation is exactly the same, since SIP Server acts as a Back-to-Back User Agent (B2BUA) between GVP and the network.

9 Technical White Paper: Genesys Solutions For Next-Generation Networks page 9 SIP Sever and GVP Network Connection Via The Chameleon Server In cases where a standard integration to a Release 4 or IMS network (or Intelligent Network for that matter) is required, Genesys deploys SIP Server and/or GVP with the Chameleon Server signaling gateway (Figure 8). The Chameleon Server provides Genesys with flexibility to connect to multiple types of networks simultaneously. Network integrations typically start with IN and/or SS7 integrations which then evolve into Release 4 and IMS integrations. More and more often the actual requirement is a co-existence of connections to multiple types of networks. The key benefit is that, architecturally, nothing changes when the network interconnects to the Chameleon Server and Genesys solutions; only the required software components change. Figure 8: Chameleon Server signaling connections Network Switch Genesys Chameleon Server SIP Genesys Applications SIP SERVER AND GVP OTHER NETWORK CONNECTION POSSIBILITIES For certain situations, Genesys has worked with its partners in order to develop customer-specific solutions. Genesys has worked with Soleo to provide connection to an Ericsson IMS CSCF for Directory Assistance services. In another case, the Alcatel-Lucent 8690 Service Interaction Gateway has been used to interface to an Italtel IMS CSCF. These cases prove that Genesys continues to find flexible and innovative solutions to support today s and tomorrow s carrier network needs with respect to the IVR and contact center market. Conclusion For Intelligent Networks, IMS networks, and almost everything in between, Genesys provides customer service solutions for telecommunications firms with evolving network needs. By separating network connectivity from Genesys solutions via signaling gateways, each of the parts can evolve at its own pace. By enabling multiple types of networks to connect to Genesys applications simultaneously, applications truly start behaving in a write once, work anywhere fashion. For more information, please contact your local Genesys sales representative.

10 Technical White Paper: Genesys Solutions For Next-Generation Networks page 10 Appendix This appendix contains a list of acronyms and references. Acronyms 3GPP AS B2BUA BICC CAMEL CAP CCF CCXML CDR CS CSCF ECF ETSI FMC GSM GVP HSS HTTP IMS IN INAP IP ISDN ISUP Third Generation Partnership Project Application Server Back-to-Back User Agent Bearer Independent Call Control Customized Applications for Mobile Enhanced Logic CAMEL Application Part Charging Collection Function Call Control XML Call Detail Record Capability Set Call Session Control Function Event Charging Function European Telecommunications Standards Institute Fixed-Mobile Convergence Groupe Speciale Mobile Genesys Voice Platform Home Subscriber System Hyper Text Transfer Protocol IP Multimedia Subsystem Intelligent Network Intelligent Network Application Part Internet Protocol, Intelligent Peripheral Integrated Services Digital Network ISDN User Part ITU-T IVR LTE M3UA MAP MGCP MGW MRF MRFC MRFP MSC MSCML MSML MTP NETANN NGN PBX PSTN RFC RTP SCCP SCTP SCXML SIGTRAN SIP International Telecommunication Union Telecommunication standardization sector Interactive Voice Response system Long Term Evolution MTP3 User Adaptation Mobile Application Part Media Gateway Control Protocol Media Gateway Media Resource Function Media Resource Function Controller Media Resource Function Processor Mobile Services Switching Center Media Server Control Markup Language Media Server Markup Language Message Transfer Part Network Announcement Next-Generation Network Private Branch exchange Public Switched Telephone Network Request For Comment Real-time Transport Protocol Signaling Connection Control Part Stream Control Transmission Protocol State Chart XML Signaling Transport Session Initiation Protocol SIP-I SIP-T SIP with encapsulated ISUP SIP for Telephones SS7 Signaling System number 7 SSP Service Switching Point TCAP Transaction Capabilities Application Part TCP Transmission Control Protocol TDM Time Division Multiplexed TISPAN Telecommunications and Internet converged Services and Protocols for Advanced Networking TS Technical Specification UDP User Datagram Protocol USSD Unstructured Supplementary Services Data VoIP Voice over Internet Protocol VXML Voice XML XML extensible Markup Language Corporate Headquarters Genesys 2001 Junipero Serra Blvd. Daly City, CA USA Worldwide Inquiries: Tel: Fax: info@genesyslab.com Genesys is the world s leading provider of customer service and contact center software with a 100% focus on customer experience and mission to save the world from bad customer service. With more than 2,000 customers in 80 countries, Genesys is uniquely positioned to help companies bring their people, insights and customer channels together to drive today s new customer conversation. Genesys software directs more than 100 million interactions every day from the contact center to the back office, helping companies deliver fast, simple service and a highly personalized cross-channel customer experience. Genesys software also optimizes processes and the performance of customer-facing employees across the enterprise. For more information visit: or call GENESYS. Genesys and the Genesys logo are registered trademarks of Genesys Telecommunications Laboratories, Inc. All other company names and logos may be trademarks or registered trademarks of their respective holders Genesys Telecommunications Laboratories, Inc. All rights reserved v.1-12/10-us