All change - Technology Information

Being a network operator these days means adapting to change at breakneck speed, with customers' expectations, particularly those of service providers, driven by promises of innovative, affordable services. Roy Rubenstein takes a look at some of the hot developments for the next generation of networks--for the near term, at least--as the competition intensities.

It seems the ink is barely dry on a network blueprint these days before plans are changed again. Next generation is quickly becoming this generation and the pace of change is leaving network operators in a quandary.

"The biggest thing telecommunications companies have to deal with is change and innovation," says Graham Finnie, associate consultant at London-based Yankee Group Europe Ltd. "It's completely alien to the way they have planned and built out operations." And there is no sign that this period of change is slowing down soon.

A good example is the way some operators have adapted their view of multiprotocol label switching (MPLS), which is becoming the widely adopted vehicle to enable the new services that will run on operators' Internet protocol (IF) networks. In particular, MPLS is adding to IP the quality of service (QoS) mechanisms that previously had only been available using asynchronous transfer mode (ATM) networks (see box, p. 20).

But in September and October last year, Dublin-based QoS Networks and Sonera Oyj of Helsinki, Finland, respectively, made significant IP QoS announcements eschewing MPLS.

QoS Networks launched its global IP-over-Sonet network, differentiating IF traffic using multiple priority levels delivered through proprietary router-based hardware. Sonera, meanwhile, launched what it claimed was the first IP-based network to fully provision QoS management and applications billing, using differentiated service protocol (diffserv) and bandwidth reservation techniques. Surprisingly, Sonera claimed there was no compelling reason to use MPLS.

Four months on and both have changed their tune. "We have matured," admits Jim Hendrickson, chief operating officer at QoS Networks. "As you roll out very large networks you need to add MPLS." The traffic engineering capabilities, QoS contribution and evolving features of MPLS mean QoS Networks' customers--ISPs, applications service providers and corporates wanting IP virtual private network (VFN) services--are, quite simply, asking for it.

While Sonera has yet to announce officially its MPLS strategy, it is already hinting at a central role for MPLS as it introduces mobile IP services.

"MPLS is one of the standards I believe should be deeply considered in next-generation networks," says Marcus Olaleye, manager, traffic routing and planning, at Sonera Carrier Networks Ltd.

In Internet time, four months is an age and network operators are being forced to hastily shift to IP-oriented networks. Gone are the days when carriers were able to plan their services at a leisurely pace and be confident of their longevity. Nowadays, it is more a case of continual reassessment of strategy.

New entrants apply squeeze

MPLS is just one of many components that is being considered or implemented by carriers as part of their next-generation networking technology.

If current networking development can be viewed as reaching maturity at the packet level, what is to come is ever greater connectivity--largely a result of developments in the optical level and its interface with the IP layer--and sophisticated applications which sit on top, and exploit, this enhanced connectivity. Service provider customers could independently provision and relinquish lightpaths as required, whether it is for broadcasting events over the web, such as live sport and concerts, or undertaking remote backup of corporate data.

These next-generation developments are enabling new entrants to turn the marketplace on its head, offering services which squeeze established operators. It also forces incumbents to examine their own strategies, to determine how best they can migrate their networks to newer technologies without sacrificing their huge investments in equipment.

The sharp rise in IP traffic, partly the result of operators moving more of their services onto IP-oriented networks, is what is fueling the change. Analysts typically claim IP traffic is growing annually by over 300% in both Europe and the United States.

The rise in peak Internet backbone traffic year-on-year is even more startling. Peak traffic, an indicator of the capacity needed in the network, is growing tenfold annually. In North America this year, it will reach 5.6 terabits per second (Tbps), claims analyst company RHK Inc. of San Francisco. In 2002 it will, the company predicts, be a staggering 73.3 Tbps.

The reason for this phenomenal growth in IP traffic is straightforward. "It offers enormous benefits in terms of the economies of scale for data services and for networking equipment," says Margaret Hopkins, principal analyst at Analysys Ltd., of Cambridge, England. IP is robust, flexible and an open standard such that services can be developed quickly and deployed widely.

The industry-wide consensus is also due, in part, to operators watching and following each other. "Seeing what the neighbors do," is how Sam Halabi, vice president, IP carrier business development, at Santa Clara, California-based Extreme Networks Inc., puts it.

"The common factor is that everyone is going to IP, everyone is deploying fiber and everyone is moving to packet data as soon as possible," says Halabi. What is left, given that this transition is inevitable, is for the incumbent operators to "deal with legacy equipment, the road map and the budget," he says.

If Europe's competitive carriers are anything to go by, the budget is there and it is going to be spent. Infonetics Research Inc., of San Jose, California, claims that by 2004 Europe's competitive carriers will have tripled their spending on data networking equipment to $5.1 billion from present levels in an attempt to gain advantage.

"Technology is the weapon alternative carriers are using to create services that distinguishes them from the incumbents," says Peter Judge, directing analyst, Europe, at Infonetics. Fundamentally, in the new economic climate, these must be services that the operators can charge a premium for: "More than just shipping bits," says Judge.

Quality of service Is the key

This is the challenge all operators face. "Data services don't generate the revenues," says Muayyad Al-Chalabi, director, core switching and routing, at RHK. "It accounts for 70% of the capacity but 30% of the revenues." Most revenue for providers still comes from voice services, but due to heavy competition revenues, these are declining.

Al-Chalabi argues that, far from creating new revenue streams, services such as IP virtual private networks (IP VPNs), which many operators are embracing, will simply take revenues from existing line services delivered using frame relay and ATM technologies. Transaction-based services, such as delivering music or video files, promise new revenue, and often from the third-party service provider, he claims. "For example, a fee for every music file or movie downloaded, charged to the content provider and not necessarily the end user."

That said, according to RHK, incumbents--particularly in Europe--are not only maintaining their Sonet/SDH networks but are making further investments in them, because of the significant revenues voice services bring. In addition, Sonet/SDH technology can support the incumbents' different type of traffic--such as modulated voice and IP data services--as they migrate traffic streams onto IP.

Part of the reason for this is that these mature Sonet/SDH networks are able to provide the level of service that customers demand.

Infonetics' study, The Service Provider Opportunity 2000, shows that if operators are to enable newer, revenue-generating services, delivering QoS to IP is a must. If customers are to adopt IP-based applications, they want assurances that they will not be penalized by service levels inferior to those delivered by circuit switched carrier-class networks. Best effort delivery for voice activated services will just not do.

"Up till now ATM has provided QoS, but now MPLS is catching up fast," says Infonetics' Judge. Surveying the equipment spend of Europe's competitive carriers, Infonetics found that 45% are using ATM in their networks, rising to 64% by the year end. Only 36% are currently using MPLS in their networks, but this will also rise to 64% in 2001. "MPLS has become accepted," agrees Analysys' Hopkins.

MPLS evolving at speed

The experiences of QoS Networks and Sonera would appear to confirm this. QoS Networks is looking to MPLS to differentiate its traffic flow, and what convinced it is the pace at which MPLS is evolving. "It used to be a dumb protocol." says Neil Timm, the company's chief technology officer. "Now it's the most powerful protocol I've seen, combining the best of layer two and layer three features."

MPLS and RSVP can reserve bandwidth and choose the nature of the connection and its constraints. Work currently underway will enable the protocol to specify the delay variation a packet can endure. In turn, the step-up in networking ability, whereby the IP layer will, be able to request a light path from the optical layer, is based on MPLS extensions.

Sonera's focus is to enable IP mobility, allowing services to be accessed in different geographical locations through both wired and wireless devices. Although it has yet to announce the role MPLS will play in bringing this about, what Olaleye will say is that MPLS will help enable a mobile Internet user roam across networks, as well as "bring more intelligence for controlling services."

Olaleye cites how with a general packet radio system (GPRS) cellular network the bandwidth is defined in the radio and handled by the base station. "The base station can't define the real-time [bandwidth] requirement from the core; that requires MPLS," he says.

One long-standing advocate of MPLS is pan-European IP services network provider Aduronet Ltd., of London, which uses MPLS as a network connection scheme to set up two different network topologies on one common network. Aduronet is using star configurations as the preferred architecture for content distribution, while using a mesh topology for the separate access traffic.

A central role in Aduronet's service plans is QoS. One of these services is content hosting through data centers based in London and Frankfurt, each backing up the other. It also plans to offer mobile IP services through personal digital assistants and laptops by integrating them into its IP VPN services.

"For mobile services we can compress e-mails into the VPN," says Brian Levy, senior vice president of technology at Aduronet, highlighting this as an example of a niche application its network will support.

More generally, he claims an Aduronet first in that its network is capable of supporting the interconnection of future mobile GPRS networks. "Each phone is effectively connected securely to the corporate network," he says, through the use of the IP security protocol, IPsec. Aduronet will not say when this service will be offered.

With QoS, the issue becomes what level of service is being offered and, critically, at what price, says Levy. With bandwidth becoming cheaper as more and more fiber is installed, the question open to debate is, he says: "Would I deploy complex technology or [simply increase levels of] bandwidth? I'm not sure."

Aduronet's philosophy is currently to provide sufficient bandwidth to ensure a very high probability that data packets are not dropped. But it is considering using MPLS as a tool to deliver several QoS levels rather than its currently planned single level, which Levy claims is "orders of magnitude better than the public Internet." MPLS will be used to set up several pipes across the network, each pipe carrying different IPsec tunneled traffic with its own associated QoS level assigned using diffserv. The motivation for having several quality levels is solely to reduce the price for the end user if the lesser levels are acceptable for a given application.

The debate as to the merits of using bandwidth rather than specific QoS mechanisms is still an open one. According to Nortel Networks Corp., of Brampton, Canada, the bandwidth approach is popular in the U.S. because capacity is more plentiful there, mainly due to more mature deregulation.

"Europe is more bandwidth conscious and more concerned about QoS," says Bilel Jamoussi, director of networking at Nortel, His view is that all operators will eventually require QoS mechanisms in their networks, and that Europe's greater concern regarding QoS is likely to make services there more cost efficient.

Carrier competition increases

Gigabit and terabit routers are among other technologies operators are investing in and highlighted by Infonetics study, in anticipation of huge increases in data traffic.

According to Infonetics, 82% of the European competitive operators it questioned will be using gigabit IP routers in their networks by the year end, while over a third will be using terabit routers.

But with the population of Western Europe currently reaching only 400 million, Judge questions just what applications and services users could be consuming and offering to justify the need for terabit traffic. "Its carriers getting carried away in their attempt to keep ahead of the competition," he says.

Self-provisioning, enabling a corporate or service provider customer to turn up bandwidth or to change service options through an Internet browser, is another service arriving this year. "The benefit is that it allows the provider to tailor services to the needs of the customer," says Judge. It also simplifies demands on the carrier's own staff when it comes to managing the network. "The number one business problem facing competitive carriers is getting good staff," says Judge.

And again there is a divide between how quickly incumbents and competitive carriers will offer such services, While 16% of competitive operators are offering it now, by year end it will be 73%. In contrast, only half of the incumbent operators questioned by Infonetics will offer this by the end of 2001.

But next-generation services account for little if the underlying network is not providing an efficient return for the operator. Because of this operational support systems (OSS)-automated systems that support the efficient operation of the network-will play an increasingly important role in next-generation networks, according to RHK. It estimates that OSS spending will add 10% to operators' gross margin by 2004, but in return it believes that for every $1 spent by an operator on OSS, as much as $3 in revenues can be accrued.

RHK highlights the recent poor performance of U.S. digital subscriber line operators to illustrate the importance of OSS automation when scaling a network. "It's the way the industry needs to go," says Leif Hoglund, RHK's director, telecoms OS. "It [the carriers] won't survive without it."

The way the industry is going was the focus of the Yankee Group when it recently undertook a study for Cisco Systems Inc. to determine the pace at which operators are migrating to IP-oriented networks. Yankee is confident that IF will be the predominant underlying network protocol in the future, and that when this occurs operators' lives will be easier. But during the transition period-the next three to six years-the industry will experience uncertainty and a shakeup, with the Yankee Group expecting two classes of operators to survive: global or regional multiservice operators which use their networks to provide applications to a broad customer base in many locations; and niche players, which use the latest technology to deliver unique services or services that undercut the major players.

What's more, it will be the niche players who dictate the pace at which the multi-service operators adapt to change, otherwise the multi-service players will find their expertise obsolete. "It's a culture of intense competition," says the Yankee Group's Finnie. "This never happened in the days of telephone exchanges."

IP handsets: observing the protocols

To the majority of users, naturally, all services are critical; it's just that some services are more critical than others. Because of this, carriers have long sought mechanisms to differentiate traffic streams in their networks.

Quality of service (Qos) gives the service provider, and soon the end customers, a way to quantify what level of service an operator's network delivers. The parameters Include boundaries on packet loss, delay, jitter (the acceptable variation In delay) and the network's minimum throughput.

Internet protocol (IP) transport involves sending packets of data or voice across a network of routers. since IP uses an inherently connectionless network, there is no guarantee when a packet will arrive. This may be acceptable for e-mail, but not for real-time movie delivery or voice-over-IP conversations.

Delivery of guaranteed QoS requires certain actions to be carried out at the packet and connection levels. Queuing and scheduling are effected at the packet level, while at the connection level actions such as reserving bandwidth and ensuring network resources are taken.

Quality of service is not new to the telecoms industry, of course. Asynchronous transfer mode (ATM), supporting voice, video and data, has offered such guarantees for some time. Now these tried and tested concepts are being translated into the IP world. These schemes effectively impose connectivity over an inherently connection less network. Put another way, all packets are no longer equal with QoS.

Several technologies are used to deliver QoS. One technique is to deploy the differentiated service protocol: diffserv. This allows the relative priority of an P packet to be defined. Typically, up to eight priorities are used, but 64 levels are possible. This information is used by an P router to determine which queue the packet is placed In. For voice-over-IP, packets are given preferential treatment over and above other less critical data services.

Another QoS mechanism, typically used in conjunction with diffserv, is multiprotocol label switching (MPLS). The labeling scheme is used by a network edge router to create paths across the network with particular constraints, such as the nature of the link, what protection is used, and even the acceptable packet delay.

A third mechanism is the resource reservation protocol, RSVP. This is used to request bandwidth resources from the network--IP routers must agree to the request between the two end points--and can also be used in conjunction with MPLS.

Throwing bandwidth at the problem to limit packet loss is yet another approach to Qos. But the general view is that the widespread use of QoS mechanisms such as diffserv, MPLS and RSVP, rather than bandwidth, is inevitable.

COPYRIGHT 2001 EMAP Media Ltd.
COPYRIGHT 2001 Gale Group