IEC Newsletter

Bridge Building to Next Generation Networks

Torsten Bethke, Director Marketing and Communication, KEYMILE

Introduction
In their core business, fixed-line network operators are subjected to enormous competitive pressure from rivals and profits are under sharp downward pressure. This article identifies the successful response to these circumstances is in the development of new broadband services, in growing sales of existing services and in reducing operating costs.

Fixed-line network operators' traditional business segments are coming under market pressure from various sectors: mobile phone providers, Internet and cable network operators are flooding the market with aggressive pricing. The following three-level program describes that the way to deal with this extremely competitive situa-tion is by maintaining the share of traditional voice services as long as possible, by establishing attractive new NGN services and by re-ducing operating costs.

Figure 1

1. Maintaining and Growing Traditional Voice Services: Maintaining and growing traditional services is one of the key issues, as significant sales with telephony in fixed networks are still possible. According to es-timates by BITKOM, about a third of all sales from telecommunications services are accounted for by legacy services.

2. Offering Attractive New Services: the network operators can increase their revenues by offering attractive new services for residential and business customers. These include for example services such as VPN and LAN-to-LAN-bridging via IP-/Ethernet for business customers, or Triple Play services for residential customers. To exploit the convergence of voice and data, network technology should be state-of-the-art.

3. Reducing Operating Costs: The basis for this is the migration of TDM-based services to modern NGN platforms. This transition modern-izes the existing network infrastructure, making it leaner, which then makes cost effective provisioning of attractive new services possible. When introducing NGN platforms it is still advisable to reduce the number of "old" existing platforms in the network. This leads to further savings in network operation. At the same time it is vital to optimize operation, ad-ministration, maintenance and provisioning processes.

Continuity of Services and Next Generation Networks
Implementing these three strategies will make a significant contribution to both the sales and the profitability of the established fixed-line network providers. A brief glance at individual services highlights the trends and opportunities provided by products for residential and business custom-ers.

The future belongs to DSL delivered over IP/Ethernet, and above all in Triple Play network environments. Fast and gigabit Ethernet are playing an increasingly large role in fixed network access for business customers. The traditional E1 interface is increasingly being eased out.

Figure 2

The crucial question is: Will NGN services actually live up to the sales expected? A glimpse at current forecasts by the Gartner Group sheds some light on the subject. The market researchers forecasted that in 2005 about 60 percent of sales by fixed network operators would be ac-counted for by voice services and that in 2010 it would only be about 40 percent. That is still the largest piece of the pie and continues to highlight the enormous commercial significance of this segment. Sales of broad-band and NGN data services will continue to thrive. In 2005 they had a market share of approximately 30 percent. According to forecasts these should increase to around 44 percent in 2010.

Telephony Migration
In the medium and long-term time frames, telephony will migrate toward a single platform in the operator's access network. This is underpinned by intelligent Ethernet/IP access technology, which facilitates the conversion of the existing legacy services.

In the transition one possibility is to use a central VoIP gateway that cre-ates a direct connection to the VoIP exchange (soft switch). In this cen-tralized solution the existing TDM network is still used in the access net-work.

The second alternative is a decentralized access gateway spread throughout the access network. This option combines POTS and ISDN connections and forms the interface to the VoIP network. In this case only legacy services are still found on the service line. The entire transmission network on the other hand already functions on an IP/Ethernet basis. In this case fixed network operators can make huge savings in operating costs in comparison to existing technology.

The third alternative consists of implementing the legacy services entirely with one gateway to the end customer and carrying out network access completely on a packet basis. This means that ISPs above all have the interesting opportunity of not just offering high-speed Internet access via DSL, but also marketing POTS and ISDN services too.

The great benefit of the first three alternatives from the network opera-tors' point of view is that migration of their telecommunications network to an All IP network can occur without requiring residential and business customers to exchange their existing terminal equipment. And NGN ser-vices can also be offered to the end customers.

Migration of Fixed Line Connections
Much more complex than voice migration is the migration of leased lines. In this case the starting point is today's PDH/SDH networks, in which di-rect connections for leased lines are, for example, available on an X.21 basis. In the future CESoPSN or TDM over IP Services will be able to carry out the same function more cost effectively. This means that fixed network operators can also easily transmit traditional leased line services via a packet-based network which cuts down on the variety of different systems in transmission technology.

Figure 3

This migration path already complies to a great extent with generally ac-cepted standards (IETF, SAToP and CESoPSN). The TDM over Packet and TDM over IP services however require a higher quality Ethernet net-work than is often currently available. Quality of service in this case may compromise low transit time fluctuations and low packet loss require-ments.

And synchronization should also be mentioned. Packet-orientated net-works are not innately designed for the transmission of synchronization information. There are two possibilities to achieve synchronized trans-mission: first, a clock can be installed on both sides, or second, an algo-rithm-driven clock recovery procedure can be implemented. This is, how-ever, an extremely complicated and complex procedure.

Migration Scenarios
Initially, the question is which network segment should be migrated first: service node, transport, access platform or the services platform. The service control platform is often migrated first, followed by the transport network, the access platform and finally the services. In reality there are more aspects. Migration must take into account the distribution of individ-ual services. And then, of course, the existing network (copper or fibre glass) as well as the condition of the individual network elements. This is different from network to network. In the majority of cases there are paral-lel infrastructures where operation has to be continued during the migra-tion process.

Figure 4

An integral part of the migration scenario in the access network is the de-ployment of a Multi Service Access IP DSLAM. Several types of these are able to implement Triple-Play services in a single compact NGN plat-form. In this way network operators can continue to support conventional telephony and broadband services and at the same time migrate to the NGN.

A combined solution allows cost-effective provisioning of traditional te-lephony and broadband services in NGNs, in which users can benefit from bandwidths at more than 100 Mbps. As is well-known, the perform-ance of DSL depends significantly on the length of the subscriber line - with increasing bandwidth the range is reduced. In order to avoid restric-tions in ranges and to reach as many subscribers as possible, DSL ac-cess points will have to move nearer to the customer.

Evolution Towards Packet-Orientated Networks

A key component of Next Generation networks is the evolution to packet-orientated networks. To do this the platform must provide Carrier-Grade VoIP Gateway functions.

In addition to supplying DSL for the Internet, POTS and ISDN-BA, various interface boards supply the end subscriber with traditional telephony ser-vices. In media gateways, the TDM voice signal can be converted to VoIP data packages. For signalling, protocols such as H.248/MEGACO or SIP, are used to implement traditional voice services in a VoIP-based soft-switch environment.

As a network management system UNEM is an important part of the NGN solution. Standardized interfaces (such as SNMP, CORBA, CLI, etc.) can make integration to superior management and provisioning sys-tems possible. All these provide an excellent basis for gradual continued development of the telecommunications network towards a Next Genera-tion solution.

Summary
In their core business, fixed-line network operators are subjected to enormous pressure from rivals, meaning that profits are under sharp downward pressure. The successful response to this pressure lies in de-veloping new broadband services, such as Triple Play over an IP/Ethernet-based network with flexible service platforms. At the same time existing services, which can provide excellent sales, should be con-tinued and the operating costs associated with them reduced. This is only possible if these traditional services are transferred to the new IP/Ethernet-based network, as this is the only way of avoiding costly par-allel operation of networks. An important feature here is to incorporate the migration strategy of individual services from the existing network infra-structure with the overall services strategy of the particular fixed network operator. In this case particular focus is placed on the access network, as on the one hand traditional services will have to be migrated and on the other hand the length of the access line will have to be reduced, so that high bandwidth for the Triple Play services or business customers' appli-cations (LAN-LAN bridging, IP VPM) can be made available. To do this, the multi-service IP DSLAM can be ideally modified to suit individual de-mands.

Educational Content Providers
Torsten Bethke, Director Marketing and Communication, KEYMILE


September 2007, Volume 2 back to index
Bridge Building to Next Generation Networks Torsten Bethke, Director Marketing and Communication, KEYMILE Introduction In their core business, fixed-line network operators are subjected to enormous competitive pressure from rivals and profits are under sharp downward pressure. This article identifies the successful response to these circumstances is in the development of new broadband services, in growing sales of existing services and in reducing operating costs. Fixed-line network operators' traditional business segments are coming under market pressure from various sectors: mobile phone providers, Internet and cable network operators are flooding the market with aggressive pricing. The following three-level program describes that the way to deal with this extremely competitive situa-tion is by maintaining the share of traditional voice services as long as possible, by establishing attractive new NGN services and by re-ducing operating costs. Figure 1 1. Maintaining and Growing Traditional Voice Services: Maintaining and growing traditional services is one of the key issues, as significant sales with telephony in fixed networks are still possible. According to es-timates by BITKOM, about a third of all sales from telecommunications services are accounted for by legacy services. 2. Offering Attractive New Services: the network operators can increase their revenues by offering attractive new services for residential and business customers. These include for example services such as VPN and LAN-to-LAN-bridging via IP-/Ethernet for business customers, or Triple Play services for residential customers. To exploit the convergence of voice and data, network technology should be state-of-the-art. 3. Reducing Operating Costs: The basis for this is the migration of TDM-based services to modern NGN platforms. This transition modern-izes the existing network infrastructure, making it leaner, which then makes cost effective provisioning of attractive new services possible. When introducing NGN platforms it is still advisable to reduce the number of "old" existing platforms in the network. This leads to further savings in network operation. At the same time it is vital to optimize operation, ad-ministration, maintenance and provisioning processes. Continuity of Services and Next Generation Networks Implementing these three strategies will make a significant contribution to both the sales and the profitability of the established fixed-line network providers. A brief glance at individual services highlights the trends and opportunities provided by products for residential and business custom-ers. The future belongs to DSL delivered over IP/Ethernet, and above all in Triple Play network environments. Fast and gigabit Ethernet are playing an increasingly large role in fixed network access for business customers. The traditional E1 interface is increasingly being eased out. Figure 2 The crucial question is: Will NGN services actually live up to the sales expected? A glimpse at current forecasts by the Gartner Group sheds some light on the subject. The market researchers forecasted that in 2005 about 60 percent of sales by fixed network operators would be ac-counted for by voice services and that in 2010 it would only be about 40 percent. That is still the largest piece of the pie and continues to highlight the enormous commercial significance of this segment. Sales of broad-band and NGN data services will continue to thrive. In 2005 they had a market share of approximately 30 percent. According to forecasts these should increase to around 44 percent in 2010. Telephony Migration In the medium and long-term time frames, telephony will migrate toward a single platform in the operator's access network. This is underpinned by intelligent Ethernet/IP access technology, which facilitates the conversion of the existing legacy services. In the transition one possibility is to use a central VoIP gateway that cre-ates a direct connection to the VoIP exchange (soft switch). In this cen-tralized solution the existing TDM network is still used in the access net-work. The second alternative is a decentralized access gateway spread throughout the access network. This option combines POTS and ISDN connections and forms the interface to the VoIP network. In this case only legacy services are still found on the service line. The entire transmission network on the other hand already functions on an IP/Ethernet basis. In this case fixed network operators can make huge savings in operating costs in comparison to existing technology. The third alternative consists of implementing the legacy services entirely with one gateway to the end customer and carrying out network access completely on a packet basis. This means that ISPs above all have the interesting opportunity of not just offering high-speed Internet access via DSL, but also marketing POTS and ISDN services too. The great benefit of the first three alternatives from the network opera-tors' point of view is that migration of their telecommunications network to an All IP network can occur without requiring residential and business customers to exchange their existing terminal equipment. And NGN ser-vices can also be offered to the end customers. Migration of Fixed Line Connections Much more complex than voice migration is the migration of leased lines. In this case the starting point is today's PDH/SDH networks, in which di-rect connections for leased lines are, for example, available on an X.21 basis. In the future CESoPSN or TDM over IP Services will be able to carry out the same function more cost effectively. This means that fixed network operators can also easily transmit traditional leased line services via a packet-based network which cuts down on the variety of different systems in transmission technology. Figure 3 This migration path already complies to a great extent with generally ac-cepted standards (IETF, SAToP and CESoPSN). The TDM over Packet and TDM over IP services however require a higher quality Ethernet net-work than is often currently available. Quality of service in this case may compromise low transit time fluctuations and low packet loss require-ments. And synchronization should also be mentioned. Packet-orientated net-works are not innately designed for the transmission of synchronization information. There are two possibilities to achieve synchronized trans-mission: first, a clock can be installed on both sides, or second, an algo-rithm-driven clock recovery procedure can be implemented. This is, how-ever, an extremely complicated and complex procedure. Migration Scenarios Initially, the question is which network segment should be migrated first: service node, transport, access platform or the services platform. The service control platform is often migrated first, followed by the transport network, the access platform and finally the services. In reality there are more aspects. Migration must take into account the distribution of individ-ual services. And then, of course, the existing network (copper or fibre glass) as well as the condition of the individual network elements. This is different from network to network. In the majority of cases there are paral-lel infrastructures where operation has to be continued during the migra-tion process. Figure 4 An integral part of the migration scenario in the access network is the de-ployment of a Multi Service Access IP DSLAM. Several types of these are able to implement Triple-Play services in a single compact NGN plat-form. In this way network operators can continue to support conventional telephony and broadband services and at the same time migrate to the NGN. A combined solution allows cost-effective provisioning of traditional te-lephony and broadband services in NGNs, in which users can benefit from bandwidths at more than 100 Mbps. As is well-known, the perform-ance of DSL depends significantly on the length of the subscriber line - with increasing bandwidth the range is reduced. In order to avoid restric-tions in ranges and to reach as many subscribers as possible, DSL ac-cess points will have to move nearer to the customer. Evolution Towards Packet-Orientated Networks A key component of Next Generation networks is the evolution to packet-orientated networks. To do this the platform must provide Carrier-Grade VoIP Gateway functions. In addition to supplying DSL for the Internet, POTS and ISDN-BA, various interface boards supply the end subscriber with traditional telephony ser-vices. In media gateways, the TDM voice signal can be converted to VoIP data packages. For signalling, protocols such as H.248/MEGACO or SIP, are used to implement traditional voice services in a VoIP-based soft-switch environment. As a network management system UNEM is an important part of the NGN solution. Standardized interfaces (such as SNMP, CORBA, CLI, etc.) can make integration to superior management and provisioning sys-tems possible. All these provide an excellent basis for gradual continued development of the telecommunications network towards a Next Genera-tion solution. Summary In their core business, fixed-line network operators are subjected to enormous pressure from rivals, meaning that profits are under sharp downward pressure. The successful response to this pressure lies in de-veloping new broadband services, such as Triple Play over an IP/Ethernet-based network with flexible service platforms. At the same time existing services, which can provide excellent sales, should be con-tinued and the operating costs associated with them reduced. This is only possible if these traditional services are transferred to the new IP/Ethernet-based network, as this is the only way of avoiding costly par-allel operation of networks. An important feature here is to incorporate the migration strategy of individual services from the existing network infra-structure with the overall services strategy of the particular fixed network operator. In this case particular focus is placed on the access network, as on the one hand traditional services will have to be migrated and on the other hand the length of the access line will have to be reduced, so that high bandwidth for the Triple Play services or business customers' appli-cations (LAN-LAN bridging, IP VPM) can be made available. To do this, the multi-service IP DSLAM can be ideally modified to suit individual de-mands. Educational Content Providers Torsten Bethke, Director Marketing and Communication, KEYMILE