WHITE PAPERtHE Time for DIAMETER Is now Why Service Providers Should Implement Diameter Today Table of Contents Introduction ������������������������������������������������������������������������������������������������2 Stay Competitive and Control Costs ������������������������������������������������������������4 Diameter Advantages in the 3G Domain ����������������������������������������������������� 4 Why a Diameter Signaling Router for 3G �����������������������������������������������������6 Conclusion ��������������������������������������������������������������������������������������������������8 About Tekelec ���������������������������������������������������������������������������������������������9 time for The diameter is now Introduction There is little secret how smartphones and tablets are affecting the worlds networks. These devices have enabled subscribers the ability to access the Internet anytime, anywhere. And with the introduction of social networks such as Facebook and LinkedIn, subscribers are connecting and staying connected all day long. The impact on service providers is huge. They are seeing their revenues steadily decline, while the cost of their network infrastructure continues to increase. To add insult to injury, over-the-top (OTT) service providers such as Google, Apple, and Amazon continue Network service providers can take advantage of a packet network today, without waiting for LTE at the RAN. This means that 3G networks can also realize many of the advantages that LTE brings by simply implementing Diameter in the core network. A recent outage at NTT DoCoMo is a good example where the network was thought to have been engineered to withstand normal data demands, but a single event resulted in an outage that lasted more than 5 hours and impacted 2.52 million subscribers. Network service providers have to spend budgets in emergency situations such as these to fix the overwhelming demand of traffic in their networks. This is CAPEX that was targeted towards something else that had to be diverted to patch the gaping hole in the packet network – capacity. So how does a network service provider move the data revenues back into their coffers, while implementing traffic controls? Do you have to move to LTE or IMS to enable new services? The answer is no. Network service providers can take advantage of a packet network today, without waiting for LTE at the RAN. This means that 3G networks can also realize many of the advantages that LTE brings by simply implementing Diameter in the core network, and with it entities such as the Policy and Charging Rules Function (PCRF). Diameter is the signaling protocol that is rapidly replacing RADIUS and SS7 throughout the network and in LTE becomes the signaling protocol that all entities speak. Diameter is also the protocol used in the new charging architecture, which means service providers can take advantage of Diameter throughout the network, and not just in the core. This is the New Diameter Network. There are many advantages to this approach, 2 which this paper will examine individually. to reap the harvest of these very subscribers at the cost of the service provider. Mobile revenues have shifted with 50% of the revenues now going to Google, Apple, Amazon, and Facebook. Over 200 million people have Apple iTunes accounts according to Apple, dwarfing most mobile service providers. Facebook touts more than 800 million active users and this number continues to grow. This means revenues will continue to move their direction, away from the network service provider and directly into the coffers of the OTT players. At the same time, the explosion in data traffic has already crippled many networks. Outages in several major networks were the direct result of excessive data traffic and the lack of any congestion or bandwidth management controls. The time for diameter is now The Need for More Competitive and Personalized Services Subscribers are spending more and more money on games, books, videos, and other products that are sold by device and over-the-top application service providers. Service providers provide a pipeline to those products and services. The pipeline alone does not bring a premium, but if the pipeline can be tailored and customized to each individual subscriber’s specific requirements, there is significant value that subscribers are willing to pay for. Service providers can personalize service, allowing subscribers to tailor their online experience to their needs, and at the same time differentiate themselves from all the other service providers. There are a number of ways to personalize services, but they all have one thing in common. The Diameter network runs the controls that enable personalization through network elements such as Policy and Subscriber Data Management. The Diameter network and a packet core allow service providers to streamline their network and take advantage of IP as the network transport mechanism, while adding the intelligence and security that the Diameter network offers. The Diameter protocol continues to grow as the 3GPP continues to define new uses for Diameter throughout the network. Because of the unique flexibility of the Diameter protocol, allowing for extensions to the protocol while maintaining backwards compatibility, service providers can be assured that Diameter will service their networks well into the future. The Diameter network and a packet core allow service providers to streamline their network and take advantage of IP as the network transport mechanism, while adding the intelligence and security that the Diameter network offers. Provide More Value to OTT Providers and Your Subscribers The Diameter protocol also provides service providers with the ability to interconnect to OTT providers through a secure connection point. This is important because it safe guards the identity of subscribers as much as possible. However, it is just as easy to provide the enriched information of Diameter to another provider as part of a premium interconnect service. For example, a service provider may implement a partnership with another content provider where the subscriber’s device type and access network is provided. This allows the OTT provider to customize their content for the specific device type and access technology, thus improving the customer experience. This makes the network that much more valuable to the OTT provider, or any other partner that may be looking to share network resources. For example, Mobile Virtual Network Operators (MVNOs) can benefit from a Diameter interconnection and the secure sharing of subscriber data and policy rules. 3 time for The diameter is now Move Revenues Back Into the Network Diameter is an enabler that allows service providers to implement more network services that carry a premium to other network providers as well as to subscribers. Diameter is also the technology that ensures secure connections using encryption; a much stronger security mechanism than what is used in present day SS7. Stay Competitive and Control Costs Diameter Is An Important Investment Now If service providers wait until LTE, routing tables will have to be changed several times in several different locations, which is time consuming and risky as errors often lead to outages and service disruptions. Diameter is the replacement protocol for SS7 and RADIUS. Even if LTE is not being implemented today, it is much more efficient and cost effective to deploy a Diameter Core Network now rather than wait. As service providers begin deploying new network elements that support Diameter, it makes more sense to connect to these devices using the Diameter interface instead of using mediation to convert these interfaces back to SS7/MAP or RADIUS and later moving them back to Diameter. This means making a temporary investment in mediation that will be thrown away later, not to mention the wasted labor costs to implement mediation. Deploying a Diameter core now allows service providers the luxury of interconnecting new elements directly into the Diameter core once, without having to redesign the network later when LTE services are launched or any other next generation wireless technology. By making this investment now, service providers can begin the migration to an all-IP network immediately, adding other key functions to the network as services grow. This is far better than redesigning the network several times as more speed is added to the RAN. If service providers wait until LTE, routing tables will have to be changed several times in several different locations, which is time consuming and risky as errors often lead to outages and service disruptions. Diameter Advantages in the 3G Domain The main advantage of Diameter in the core is the ability to personalize services for subscribers using the Policy Server (PCRF). This network element uses Diameter to communicate with other parts of the network where the policy enforcement is actually implemented. Present day Serving Gateway Support Nodes (SGSN) and Gateway GPRS Support Nodes (GGSN) already have a Diameter interface in most cases. This means the PCRF can be implemented throughout the network and traffic management can begin immediately without launching LTE. 4 The time for diameter is now This also means that service providers can offer tiered services, day passes and other personalized services offered using the quota management capabilities of the PCRF and subscriber information in the integrated Subscriber Profile Repository (SPR) and begin adding value to the 3G network while planning for 4G at a later time. In fact the argument could be made that LTE does not ensure any service provider will be able to increase their ARPU without also implementing Diameter in the core and offering personalized services. This makes the case for implementing Diameter now even stronger. Implement IP in the Charging Domain IP brings many advantages by itself, and certainly everyone has recognized the value of using IP in the core of the network. However, IP is just as important for charging as well. In fact, charging can benefit from IP immediately, eliminating a major headache for service providers. To implement IP in the charging network, Diameter is used to interconnect all charging entities into the charging systems (both online and offline). IP has been recognized as a major advantage in the billing domain as more and more data is being generated for the purposes of billing. This is especially true in online charging domains. There are numerous messages between the various network elements delivering a service, to the online charging system. Credit balance, authorizations, and credit notifications generate a lot of data back into the core to the numerous service delivery platforms in the network. As subscribers use more and more data for services such as video, longer data sessions for social networks, and ecommerce, this traffic continues to grow in volume. This makes the case for moving to IP and Diameter even stronger today. As subscribers use more and more data for services such as video, longer data sessions for social networks, and ecommerce, this traffic continues to grow in volume. This makes the case for moving to IP and Diameter even stronger today. Implement Policy to Manage Data Traffic and Deliver New Services The Policy Server is a Diameter-based entity that was introduced as part of the LTE architecture but has since been implemented in 3G networks where Diameter is implemented. Policy enables service providers to implement controls on a per-subscriber basis for managing data traffic. This is important because networks with no policy have required higher CAPEX to support data growth, while thoses with policy have reduced their CAPEX and OPEX. Why? Because they are now able to control how much bandwidth each subscriber is allowed to consume, as well as when they are allowed to consume it, and how they are allowed to use it (with social networks, or other OTT services). Policy is the only means for a service provider to get control of the packet network while also introducing some new and interesting revenue opportunities. 5 time for The diameter is now The first implementations of policy were about bandwidth control, but service providers then learned they could charge some subscribers more than others, through usagebased service plans. There have been many more creative applications of policy where new revenues are being recognized by adding value to OTT applications such as Facebook and YouTube. For example, a network service provider realizes that the majority of their subscribers are paying for lower tier services, but they occasionally like to access YouTube. With their current service plan, they are not allowed enough bandwidth for a positive experience Without Diameter, the Policy Server would not be able to communicate with the other entities without implementing expensive mediation equipment. This customization relies on the Diameter protocol to communicate the rules between the Policy Server and the policy enforcement entities in the network. Without Diameter, the Policy Server would not be able to communicate with the other entities without implementing expensive mediation equipment. viewing streaming videos, so their YouTube experience is not a positive one. However, YouTube could be willing to subsidize their service plan by paying the network service provider a premium to allow subscribers in the lower tiers more bandwidth when they access YouTube, if the subscriber opts in. This is one way service providers can improve the subscriber experience. Why a Diameter Signaling Router for 3G Diameter is the next generation technology for control throughout the network, but it is also the next generation protocol for services and charging. What is missing from the Diameter network is a centralized point of control and routing. A centralized routing function that acts as the hub in the Diameter network providing security, load balancing, and congestion control. The Diameter Signaling Router (DSR) is designed to provide these functions and prevent service providers from deploying a mesh network. Mesh networks have never worked historically, and always create major concerns for networks for a number of reasons. Routing tables are the biggest issue, because every network element must not only connect to all the other network elements, but also be able to route to all the other elements. This results in complex routing tables that have to be repeated at every element. Congestion control and load balancing are another issue in a mesh network. Already we have seen service providers using load balancers at the edge of their networks in an attempt to increase the efficiency of the network. However, these point solutions do not scale, and as traffic increases the load balancers quickly become overwhelmed. Load balancers are also designed to manage connections and not data, so when a connection is lost (which happens frequently in IP networks) the load balancers have to be manually reset to properly balance loads across many connection points. 6 The time for diameter is now There is no security in a mesh network, as routing details have to be provided at every node therefore making it impossible to hide the addresses of your most critical network elements. This makes connecting to other networks especially precarious, because addresses stored in the Home Subscriber Server (HSS) and sometimes policies in the PCRF must be shared with interconnect partners, exposing the network. A DSR resolves all of these issues by acting as a centralized connection point for all routing. Routing translations in other network elements is simplified, because as new elements are added, only the address of the DSR needs to be added. The DSR then makes all routing decisions for the network. A DSR also provides load balancing. Because the DSR is a Diameter Routing Agent (DRA), it is capable of determining the best routes for all data, and based on data volume select the best route to be taken. But the DSR provides other values as well. When deploying a PCRF or when converting the charging network to IP, the DSR provides valuable services. When deploying a PCRF or when converting the charging network to IP, the DSR provides valuable services. DSR as a Policy Proxy When implementing policy in the network, there is a requirement for a policy rule to be connected to a subscriber. Whenever that subscriber begins a data session on their phone for example, and they connect with the GGSN, the GGSN needs to send a query to the proper PCRF to receive the rules to be applied to that subscriber. There is more than one PCRF in any Tier 1 network, so this can be a challenge. There needs to be a function in the network that can route these queries from the GGSN and DPI platforms to the proper PCRF. This is known as subscriber policy binding and is a function of a DSR. The DSR maintains a routing table that associates each subscriber with a specific PCRF, and can then route policy queries from any network element to the proper PCRF in the network. The DSR is providing this function today in Tier 1 networks allowing them to efficiently manage their PCRF connections in the network and centralize the routing functions associated with policy to the DSR. DSR as a Charging Proxy Just as the DSR does for policy, the DSR can also provide a charging proxy function to the network. When changing to IP in the charging network, there are many servers behind the online charging system. Reaching these servers requires routing tables in all of the entities responsible for generating charging records. 7 time for The diameter is now To make matters more complex, the servers are used for different services and different subscribers. This means there is a need for an additional level of intelligence in the charging network that is able to route charging messages to the correct charging platforms without creating huge, complex routing tables all over the network. The DSR works as an excellent Charging Proxy, providing this routing function while also adding another level of security to the charging network. Using the same security algorithms used for the rest of the network, the DSR ensures that the charging network is able to take advantage of IPsec throughout the network. There is a need for an additional level of intelligence in the charging network that is able to route charging messages to the correct charging platforms without creating huge, complex routing tables all over the network. It is for this reason that the DSR is the best means of supporting interconnections to other networks just as STPs in the SS7 network provide this very same function. However, an STP is limited to gateway screening, which is not encrypted and not as secure as what Diameter is able to offer. A DSR provides security in the network through IPsec in the core and Transport Layer Security (TLS) to outside networks. IPsec uses encryption on a peer-to-peer basis, which means the message is encrypted each time it passes through another DRA. This is the strongest means of encryption, and only those network elements acting as a DRA with encryption keys can decipher a Diameter message. This makes the DSR an excellent interconnect gateway when connecting to outside networks. Topology Hiding allows the DSR to substitute the address of any sending network element when sending outside the network and maintaining a connection map internally so it knows where to send responses. DSR as an Interconnect Security Gateway When connecting to a partner network for roaming or shared services it is imperative that there is a single connection point rather than unbridled access to all the network elements in your domain. This is especially true in Diameter. Conclusion The Diameter protocol is an enabler. It allows service providers to add new functionalities to their networks that bring added value to services. By adding more value to services, service providers deliver more than just a pipeline; they bring value to the table and subscribers are willing to pay for this value. In order to take advantage of Diameter, there are fundamental changes that must take place. Of course, TCP/SCTP/IP is the transport in the New Diameter Network, and needs to be deployed throughout the core, as well as in the back office to support charging systems. 8 The time for diameter is now A Diameter Signaling Router (DSR) is the best means of managing the Diameter network and serves as the focal point for managing connections in the network. The DSR is the most critical component in the New Diameter Network and should be the first addition to a 3G network before jumping on the 4G bandwagon. The New Diameter Network is the foundation of a successful mobile data business, and when implemented properly, will allow service providers to begin reaping new revenues now, without waiting for LTE. ABOUT TEKELEC Tekelec’s intelligent mobile broadband solutions enable service providers to manage and monetize mobile data traffic. We are the architects of new Diameter networks, including session, policy and subscriber data management. More than 300 service providers use our market-leading solutions to deliver innovative services to consumers and enterprises. For more information visit www.tekelec.com. 9 Tekelec Global Headquarters +1.919.460.5500 888.628.5527
[email protected] EMEA +44.1784.437000 APAC +65.6796.2288 CALA +1.919.460.5500 Tekelec has more than 300 customers in more than 100 countries. For information on our worldwide offices, visit the Tekelec website at www.tekelec.com/offices. This document is for informational purposes only, and Tekelec reserves the right to change any aspect of the products, features or functionality described in this document without notice. Please contact Tekelec for additional information and updates. Solutions and examples are provided for illustration only. Actual implementation of these solutions may vary based on individual needs and circumstances. © 2012 Tekelec. All rights reserved. The EAGLE and Tekelec logos are registered trademarks of Tekelec. All other trademarks are the property of their respective owners. TKLC-WP-031-09-2010 www.tekelec.com