Understanding what carriers mean when they say "IP"

Carriers have divergent and slippery definitions of IP, says Richard Chirgwin, who explains what they mean when they discuss the protocol.

You might be forgiven for thinking that TCP/IP has been with us for many years. After all, most businesses gave up on other protocols and used nothing but IP routers since the mid-1990s.

So when a carrier like Optus releases its IP Index - an extensive research project covering the adoption of IP technologies in 229 enterprises - some confusion might be considered reasonable. If everybody is already using TCP/IP, what is left to measure in adoption?

The point is that telcos look at TCP/IP from their own point of view. It's not about whether you're using TCP/IP – it's about whether the telcos are able to turn the protocol into a saleable service.

So here's a primer on how the carrier views the IP world.

1. It's Not About the LAN

The carrier sees IP-based services as an emerging class of managed services, or semi-managed services. In the carrier world, an IP-based service is designed to deliver enterprise connectivity as a generic Layer 3 service. What changes, from the enterprise customer's point of view, is that management of both the physical network and inter-office routing passes to the carrier.

In the “legacy” world, the carrier provided links that users connected to their routers, and the users managed the routers themselves. In the world of carrier-based IP services, the carrier progressively gets past the network boundary and helps customers manage their routing and the applications that live on the IP network.

In addition, in a fully-managed environment, the carrier will also assume responsibility for at least some of the customer's IP-based applications - those offering significant value-add opportunities, such as the implementation of enterprise-wide IP telephony, IP conferencing applications, and IP VPN access to support the remote and mobile workforce.

2. What About the Connection?

A significant number of businesses still use so-called "legacy" data services for inter-office connections. Frame Relay and ATM are certainly in decline, but there remains a substantial installed base that's only midway through its migration. The leased line, which includes services such as, but not limited to, Telstra's DDS Fastway and X.163 services, may be considered a legacy service, but there remain many thousands of leased lines still in active service.

Moreover, although carriers generally favour access networks such as business-class DSL and (where it's available) metro Ethernet services to connect customers to IP-based services, legacy services can still be supported in an IP-based carrier environment. There will remain locations in Australia, such as remote branch offices, where the leased line is the most practical way to get physical access to the carrier network.

TCP/IP doesn't care about that, because it doesn't stipulate what kind of network exists at the physical layer (wonderfully illustrated in the April Fool's RFC, IP Over Avian Carriers, which proposed a protocol for using carrier pigeons to carry IP packets).

From the Optus IP Index

Optus last week announced its ‘IP Index,’ the results of which we summarise here.

Teleconferencing and Videoconferencing are now in use in 45% of enterprises surveyed. Videoconferencing, surprisingly, suffered a drop from 2005 (27%) to 2006 (19%) but has recovered strongly.

Teleworking is now entrenched in the workplace, with 44% of employees working somewhere other than the office at least one day per week. Optus expects this to drive adoption of wireless broadband, and predicts that the proportion of employees using this technology will rise from 28% to 40% over the next year.

Convergence of voice and data networks is a big theme. Only 16% of respondents reported no plans to converge their voice and data networks in 2008, and 55% of respondents said they have partly or fully deployed VoIP in their networks.

Call Cost is still the focus of customers deploying VoIP. This was the focus of 63% of respondents, while lower support and maintenance was important to 42% of respondents and simplifying moves-adds-changes was also endorsed by 42% of respondents.

Quality of Service is important in enterprise deployment, with 55% of respondents saying they use QoS to prioritise their traffic.

Mobility also rated highly, as does the desire to improve mobile access by deploying 3G. Currently, 3G handsets comprise 37% of mobile devices in use in enterprises, and the Optus IP Index indicates that this will rise to 52% in one year's time. As the use of 3G handsets rises, respondents are also indicating they expect growth in non-voice mobile applications. E-mail stays at the top of the list for enterprise mobility (nominated by 51% of respondents as likely to grow in usage next year), followed by Web browsing (47%) and video calling (41%). Interestingly, only 29% of enterprises predicted growing use of tethered 3G modems in the next year.

Carriers are taking advantage of IP's agnosticism by adding 3G access to the mix, both to support mobile workers and to provide office backup links.

3. Doesn't This Mean Sending Data Over the Internet?

Probably the biggest confusion carriers have to face in promoting IP-based services is the misconception that they're asking customers to run mission-critical applications over the public Internet.

While the Internet can be part of the IP-based carrier service, it's not the main game. In the carrier world, an IP-based service is, first and foremost, a private network in which the carrier manages all of the network elements (the links, the routers, the backbone and the servers) on an end-to-end basis.

For the enterprise, that means exposure to the Internet can be limited and managed. Access to the Internet for employees on the network is over the same links, but the difference is that all Internet traffic entering the carrier's network is passing through a gateway that's hosted and managed by the carrier.

And because of the protocols in place - this is not the place for a long tutorial no MPLS, the suite of protocols that underlies most carrier-based IP services - the traffic of one customer is segregated from the traffic of another customer. That means that should one customer suffer a security breach, other customers on the carrier's IP network won't inherit the infection.

However, the Internet will still have a big part to play, since it's the primary channel into the network for remote workers and mobile workers. Those people will access the Internet over the home or mobile broadband connection, with the carrier providing security in the form of IPSec or SSL encryption and delivering that traffic to the customer's enterprise network.

The other big difference between the carrier IP service and the public Internet has to do with performance. Since the carrier owns and manages all of the network elements, and since it's typically used MPLS as an overlay protocol to provide traffic management, the carrier can offer something that you can't get on the public Internet: service level guarantees. If your application needs performance good enough for high-definition videoconferencing (something you're unlikely to get on a generic broadband Internet service), the carrier will design your network so the performance is there.

Typically, the customer will buy services that devote different amounts of the bandwidth to different types of traffic, so that voice gets top priority while e-mail and browsing are still treated as "best effort" applications.

4. What's In It for the Carrier?

IP has long been seen as a disruptor, since any two offices could be connected by routers, with the carrier's role restricted to providing relatively low-value access services ("bit pipes"). Private, business-grade IP networks give the carriers a chance to take ownership of the value chain as well. Not only can the carriers relieve the customers of the growing complexity of managing (and particularly securing) routed IP networks, the carriers also have their eye on applications the enterprise customers might be leaving in the "too hard" basket for the time being.

IP telephony is the most obvious example of this. Most enterprises intend to put IP telephony in place at some point (and, as the Optus IP Index data discussed later shows, many already have), but it's a complex and challenging exercise. The carrier, however, has expertise in running voice networks, and since these have been progressively adopting IP technologies over many years, the carriers also have experience in implementing and managing various kinds of IP telephony environments.

Another example is the deployment of videoconferencing. IP technologies have standardised and simplified videoconferencing to such a degree that it's now considered a serious travel replacement, rather than being something you use in emergencies and otherwise hide in an unused meeting room. Even so, it's a demanding application: if the carrier can provide a network that handles IP videoconferencing natively and still provides performance suitable to the application, so much the better.

And don't forget those bit pipes that underlie the network. They might sit at the bottom of the value pyramid, but they're still the bread-and-butter of the carrier business. If the carrier IP service encourages customers to deploy more bandwidth-demanding applications, so much the better.

Finally, it's worth remembering that managed networks are more “sticky” than traditional legacy networks. The customer that manages its own networks has the expertise to move its network between carriers, should a better offer come along. Where the customer has handed over management of both the network and the applications running over that network, the customer will think twice before switching providers.

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