The era of international TDM is nearing its end, hastened by forums that are setting standards and providing exchanges where the new traffic can be interconnected
 
 
 


As the telecoms world moves to IP and ethernet standards, the industry is creating new organisations in order to enable all-IP operators to exchange traffic in the new technology — just as they can still interconnect legacy services.

International wholesale carriers are working on harmonising their IP services through the i3 Forum, which was announced in June 2008 and has expanded its work programme from the initial task list that focuses on bilateral voice.

“The i3 Forum was created because the industry is about to go through a major transformation,” says Philippe Millet, the France Telecom executive who chairs the group.

“All carriers are moving to an IP world and this will enable a new set of services and products.”

At the same time another industry organisation, the Metro Ethernet Forum, has set up a commercial carrier ethernet exchange, CENX.

“We saw the need for an interconnect,” says Nan Chen, the chairman of the MEF, “so we formed an exchange with a number of carriers.”

The first to be public on the fact that it is interconnected is Verizon. “The right model for Verizon was via a neutral exchange,” says Quentin Lew, a senior vice president at the carrier. “We’re constantly meeting carriers from Asia and Europe wanting to reach the US and the partnership is critical for us.”

Ethernet has the advantage that it is a long-established standard, but the i3 Forum is concerned that all-IP networks will need services to work across a number of different networks, requiring a common set of standards.

New everything

“As we transition to the all-IP world, we will have new equipment and new networks,” says Millet, who is VP for customer marketing and development at France Telecom’s international wholesale solutions unit. “It’s not just on the technology side — it’s new everything.”

Service providers already have the dilemma of wondering how long they need to run legacy services and IP-based services in parallel. “That’s true for interconnections as well. We need to get rid of the legacy as quickly as possible. If operators stop in between, they will get the worst of both worlds.”

The i3 Forum’s task is “to help the whole industry transform”, he adds. “The new IP environment is very fuzzy. It’s not yet very stabilised. People are asking questions about quality, security and so on. We need to move very quickly.”

It’s a complex task, because each operator is moving at a different pace, and each works in a different competitive framework in its home country. That’s why the i3 Forum “decided to focus on the international market, where all transactions take place in the same space”.

The international market is free of regulators, he notes. “It is completely homogeneous, and so it is easier to discuss matters and come up with recommendations.” And, he adds, agreements for international coordination are “a great starting point for domestic services”.

The i3 Forum is not a standards body, he emphasises. “That’s for the existing bodies.” And it’s not prescriptive — the forum won’t be determining which codecs operators should use, for example.

In the 18 months or so since it was announced the forum has worked on “five interconnection models” including the whole range from private networks to the public internet. “Each makes sense in a particular situation. We’re in this business and we know what we’re talking about.”

Members of the i3 Forum include most of the world’s large wholesale operators, including AT&T, Belgacom, BT, Deutsche Telekom, France Telecom Orange, NTT, Reach, Rogers, SingTel, Sprint, Tata, Telecom Italia Sparkle, Telefónica, TeliaSonera, Telus and Verizon.

“We include 34 carriers, serving over 1.5 billion people in more than 100 countries.” Those carriers already carry 80% of the world’s international voice traffic.

Migrating TDM services

The latest phase of the forum’s development, which started in mid-2009, included specific projects on migrating TDM services — including ringback tone, fax and ISDN — and enabling service level agreements to be observed across different carriers.

Now the forum is looking at further features, such as what happens to quality of services for calls that start on TDM and end up on IP, or the other way round. There are questions of routing and addressing, number portability and issues of fraud and security management.

“We want to define the building blocks to route the services in the most efficient way. For each service you have to ask who’s calling, what quality do you require, and what codecs do I have available, and what’s the cheapest route?”

It’s all focused around interconnection. “There’s nothing you can do on your own,” says Millet. As the IP transition gathers pace, “there are many questions, but if you have answers, you’re not sure if the other carriers have the same answers”. The result: “When you try to make something work, it won’t. This is seen as something that is slowing down or stopping the migration.”

The i3 Forum is for carriers only, not vendors. “We are the guys who are doing it. We have the customers making calls and terminating calls. Decisions are made from a carriers’ perspective.”

But it is for mobile as well as fixed services: “We’re working with the GSM Association,” says Millet.

Now it is taking up the challenge of high-definition audio for video conference services, as operators seek to make them interoperable. “Telepresence is a great service but for the time being it’s single vendor. You want to be able to call everyone.”

Tipping point

How long does the industry have for the full IP transformation? “Either it happens but in slow motion, in which case it will take five to 10 years, or else there’s a tipping point, where we reach critical mass and it all happens in two or three years. It’s hard to tell.”

And, as the industry nears that changeover, new issues will arise, he has no doubt. “We’ve focused on the biggest issues for voice in the TDM to IP change, but I’m sure there will be other topics coming up,” says Millet.

Chen’s Metro Ethernet Forum has been running rather longer than the i3 Forum. It was set up in 2001 with just a handful of companies, vendors and operators, and is now the defining body for carrier ethernet services, metropolitan, national and international, with 150 members.

The MEF expects carrier ethernet business to grow rapidly, from around $25 billion this year to close to $40 billion by 2013 — though international and wholesale represent only a small part of that market.

Nevertheless CENX, of which Chen is CEO, is a big step in realising the dream of achieving carrier ethernet interconnection between operators.

The exchange has three US points of presence so far, in New York, Los Angeles and Chicago, but its map of the world shows a further seven planned locations in the US, three in Europe, five in the Asia-Pacific, including Australia, China and Japan, plus locations in the Gulf, India, Brazil and South Africa.

Verizon, which has recently united its US and international wholesale business into one unit, was the first carrier to connect to CENX — though Level 3 is a recent further addition, in late January 2010.

Extending reach

“The exchange enables enterprise customers to extend their reach,” says Lew. “We will provide end to end services over the globe over time.”

Verizon is already seeing the effect of the transformation from TDM to IP, he notes. “There’s a flattening of the growth in standard private lines, such as T1 and E1, and a migration to ethernet because of the bandwidth and scalability.”

In the US operators are meeting a surge in demand for mobile broadband data — through the introduction of the Apple iPhone and other smartphones — by swapping base station backhaul from T1 circuits to ethernet.

More demand for ethernet comes from enterprises that are major users of bandwidth, in finance, education, manufacturing and medicine. “They are all driving higher bandwidth and a move from private lines to ethernet,” says Chen. “I hate to be visionary, but the MEF set this out nine years ago.”

CENX will help ethernet carriers around the world — in Hong Kong, London, Frankfurt and Singapore, said Chen — to drive ethernet ubiquity.

“One connection into CENX will mean a carrier can access any other service provider virtually,” says Lew. “From the point of view of opex and capex it makes sense.” International carriers will be able to reach Verizon’s footprint. “That will knock down the barriers to entry.”

 
 
US and international carriers

The alternative, as ethernet services spread, would be for each carrier to negotiate interconnection to every other carrier. CENX will overcome that need by providing a central point of contact, says Chen. “We’re in discussions with 20-30 carriers, domestic and international, mostly international.”

Sophisticated software at CENX means a service provider can show where its carrier ethernet network reaches — down to city streets and blocks. “You can see right down to buildings,” says Lew. “The portal allows us to show our assets.”

So will this mean a rapid shift towards carrier ethernet? Chen believes things are going his way. “The vision of carrier ethernet is being realised,” he says. “People are working really hard.”

We may be approaching the IP tipping point; perhaps the ethernet tipping point won’t be very long after that. GTB