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Thursday, April 27, 2006


What is ‘Broadband’?

The definition of what ‘Broadband IP’ constitutes is fairly open to interpretation. While there are numerical definitions of what a ‘Broadband’ connection is, these numbers vary depending on the operator (and what it wants to advertise) and the nature of the service. As an example, if you are in an IM text chat session with your friend and are not exchanging rich media, does it really matter if you are on a 44kbps link or a 3mpbs link ? However, if you were in a Skype audio/video chat with a colleague, you will certainly feel the difference between a 44kbps link (choppy voice/video) and a 3mpbs link (smooth video and audio) . Therefore, the definition of ‘Broadband’ over IP is closely tied to the nature of the service that is to be delivered.
Having said that, for the scope of this paper, let us assune that broadband is any data service that offers a data rate of higher than 56kbps. Practically, most wireline broadband providers start at a minimal ‘broadband’ rate of 128kbs/256kbps. While early versions of second generation wireless technologies such 1xRTT and 1xEVDO offer lower data rates, it is a safe assumption that a majority of ‘broadband’ usage is above the 128kbps data rate.

Growth of Broadband

The success of a service depends largely on two factors: a) The customer need for the service and b) the quality of the service. In some cases, the first factor is so important that users are willing to accept degradation of quality (the 2nd factor). The proliferation of cell-phones worldwide, with dropped calls and jittery voice is a good example of such a service where the uniqueness (mobility) of offering overshadowed the quality concerns. Having said that, cell phone coverages have significantly evolved over the years, since eventually, consumers will expect ‘acceptable’ quality. Therefore, it is important to analyze the growth of Broadband before we can discuss the relevance of the services on top of it. WebsiteOptimization has some interesting data on Broadband Growth, where they show that in the USA, in 2000, the total % of ‘dial-up’ users within the ‘internet connected population’ was 74%, while in 2006, this rate dropped down to 36% (in other words broadband users are now 64% of the total internet population). In terms of the proliferation of Internet in countries, InternetWorldStats reports that the number of Internet users in the USA is currently at 68.6% of the US population while world wide, the Internet users are at 16% of the total world population, up from 5% in 2000.
The relevance of Broadband penetration is a function of the internet penetration of the region in question as well as the market segment within that region. As an example, Asia’s overall internet usage growth since 2000 is over 210%, EU is 180%, North America is 110% (source)
In short, this tells us three things:
  • It is obvious that different regions will have different growth numbers for internet usage (a function of the economy amongst other factors). However, each region has a very high grown rate which implies that the rate at which internet penetration is increasing is very high.
  • As the internet penetration grows, it is expected that the % of broadband users within the Internet users will also substantially grow (as shown above by individual statistics in the US as one region example) due to the fact that broadband rates are driving down and there are new innovations for delivering broadband to the last mile (more on this later)
  • Finally, from an innovative service deployment perspective, it also tells us that the penetration of broadband usage within the healthy internet growth worldwide means the ‘last mile access’ (from the provider to the user) is capable of delivering media rich services. After all, even if the network is connected via high-speed fibers, if the connection to the user is bandwidth restricted, then this severely limits the usability of the internet for high speed data services from a user perspective.
Factors that changed the ‘Communication Landscape’ as we know it

The rapid growth and related excitement about leveraging the Internet for communications can be broadly attributed to some key technologies and market shifts in the past decade:

  • The penetration of the Internet around the world – discussed in detail in previous sections.
  • Voice over IP and Vonage – In the 1990s, using the Internet to deliver voice calls was a much talked about topic. (actually, voice over IP as concept is older and there were several proprietary protocols that dealt with specific requirements, but it took till the late 90’s for standardization momentum to pick up). Competing protocols such as H.323 and SIP were introduced, both of which promised to utlize the internet to deliver global voice calling around the world. Using the internet, which is a de-regulated and distributed packet network to be able to deliver voice calls was exciting to everybody except the incumbent carriers because it allowed them to play in the communications space without heavy investment in infrastructure. Detecting this trend, incumbent carriers also reduced calling rates while trialing VoIP themselves. However, no one really was ready to deploy VoIP for consumers (there were several enterprise VoIP deployments, where QoS is a lesser issue). This was till Vonage took a leap forward and introduced VoIP calling for the masses. For a low monthly rate, they offered a bundle of enhanced services which were charged at a premium from LECs. This effort had a worldwide ripple effect on two fronts. First, consumers and providers realized VoIP as a technology had the potential to work well and threaten to replace PSTN lines (admittedly, there are still issues of emergency calling and overall consistent quality issues which are being addressed.) and secondly, it was clear message to the LECs that this was a disruptive technology that could potentially displace them from a multi-billion dollar market.
  • 3GPP – While Vonage and a slew of ‘me too’ providers penetrated the wireline world as a viable alternative of Broadband IP being used to replace PSTN lines, there was still a large void in the ‘mobile world’. The challenges of a mobile network are much more than in fixed networks (QoS, Roaming agreements, location tracking, Emergency calling, latency, air interface optimization and more). From a technology perspective it was fairly obvious that it was only a matter of time that Broadband IP somehow penetrated into the mobile world and threatened the monopoly of wireless carriers. However, before that happened there needed to be significant investment in preparing the wireless network for the IP infusion. 3GPP took on the responsibility of defining an all IP architecture (in stages) which would provide carriers a migration path from switched to packet based networks and thereby ‘stay in the game’ and be able to retain their customer base as well as fight the challenges posed by alternate technologies that threatened to bypass their network (next point). Interestingly, 3G licenses were put on bid for astronomically high costs for carriers. Once those costs were sunk in, unfortunately, the worldwide market dipped significantly
    during 2001-2003 and revived up again end 2004. Once the market was up again, carriers had already invested too much into 3G licences and it was (and is) in their interest to make it a reality soon. In 2006, there are already several 3GPP trials in the market and we expect to see all-IP 3G deployments by Q2 2007.
  • Distruptive technologies: WiFi, Skype, Peer2Peer and others: While all of this happened, several technology and market innovations took place which drove consumers faster towards ‘using the Internet for communication needs’ than ever before. The first was WiFi – the industry rapidly made progress in WiFi and related technologies where the user could access a high bandwidth internet connection with limited mobility. The mobility range continued to improve with new mobility standards such as 802.11e and beyond. In addition, recognizing the fact that new standards take years to deploy and stabilize, innovations by companies such as Tropos, Cisco and others resulted in new network topologies that increased the range of existing WiFi standards by creating a mesh of interworking routers hosted on city lamp-posts to provide a larger mobility range to users. At the same time, services such as Skype were introduced which provided excellent audio/video quality and easy connectivity with the PSTN which further drove consumers to adopt broadband IP. Finally, solutions such as Skype demonstrated that the Internet was ready for providing VoIP communications in a peer2peer fashion – you don’t need to sign up with some ‘central provider’ to reach another user (as long as the other user is also on the Internet) – the Internet was the ‘provider’.
  • Google – Finally, this has to be said: Google happened. This was not just a demonstration of a ‘search engine’ company. It was the ushering of a new era of communication where google demonstrated how different streams of content – voice, video, data could be effectively grouped together and personalized in such a way that the Internet suddenly became a respository of ‘useful information’ for each individual instead of ‘Raw Data’ using a single interface. In addition, they also demonstrated en-masse how technologies such as AJAX could be used to present attractive User Interfaces which compete with the effectiveness of local desktop applications.

Finally, what are the applications of Broadband-IP ?

We talked about infrastructure & broadband penetration. We talked about disruptive technologies. So how do we tie this end to end ?

Imagine that you are on your desktop PC chatting with your friend. In addition to chatting, you are also sharing photographs from your flickr account for a recent trip you and your friend took. Your friend and you are looking at the photographs together as well as collaboratively editing the photos by adding notes about what you were doing in various photos. Ofcourse, your ‘chat’ is using ‘voice’ (talking), ‘video’ (you have a web-cam) as well as ‘data’ (sharing textual notes). While conversing, you decide to drive down to your friend’s house, so you click on a button and the ‘session’ automatically gets transferred to your cell phone, using VoIP. However, your current network operator does not provide you with enough bandwidth to host a video call, so the session automatically removes the video session when the call transfers to your cell phone. At the same time, you use google maps in your cell phone to map the exact driving directions to your friends house. Your friend in turn can track your current location from home, because you have allowed him to view your location updates. That way, if you are lost, your friend knows where you are without you having to figure out !

Ofcourse, the service could go on an on with the potential combinations that could enhance the definition of what we know communication to be today.
So really, as an answer to the applications of Broadband-IP, the scope is enormous, almost infinite, limited to one’s imagination and fair business reasoning of which service makes sense to deploy and which service would a user be willing to pay for as opposed to being a free service with alternate revenue mechanisms (advertising, as an example).

Crystal Ball

So what’s the next wave ? Well, really, 3G and Fixed Mobile Convergence are too new not to be considered the next wave. But really, beyond that, another area I see that will contribute significantly to the ‘end-end Broadband IP’ dream is that of Home Networking. In 2001, I did quite a bit of work with Telcordia, Columbia University and others to define extensions to SIP for home networking. Unfortunately, the economy tanked then and the timing was just not right. But I am betting this field will be the next to mesh into a common protocol infrastructure in this decade. We shall see.

Monday, April 24, 2006

UN-Geekification (or the transition from hands-on to hands-off)

A good friend of mine made this hilarous statement: (he was referring to his corporate climb, where he recently (8 months ago) progressed from being a key architect to a ‘upper strata persona’.
….I mean, I am wearing blue shirts and black pants to work for the past !@#$ing 8 months and all that people talk to me about is c++ !!

I guess it is time to get Un-geekified !

When is your un-geekification process complete ?
  • When you can spend an entire day at office doing nothing but hitting ‘refresh’ in your inbox every 5 minutes
  • When you can successfully attend every meeting and summarize your key action as “As I understand it, I will ensure that my people will talk to your people”
  • When instead of saying “No, my product does not do this feature”, your natural reaction leads you to say “Based on my current understanding, which I will run by my core team, I believe this feature is part of an enhacement package for which we can positively work with you for a mutually exciting roadmap as part of our professional services initiative, assuming that this feature introduction is benefitial to both parties in a win-win environment”
  • When, in response to a direct question from an engineer “What do you exactly do?”, the only answer you have is a deep sigh and a shake of the head saying “Too much…. Young urchin ! too much ! I hope you are never in my shoes….” As you race off somewhere else.
  • When, if someone asks you a remotely technical question, your eyes glaze right through him, like he never existed.
  • And finally, when you call your ‘IT’ department, complaining that your mouse and keyboard no longer work, and the support rep. comes in and plugs them back into the usb ports, because a while ago, you yanked it out with your pot-belly as you tried to get out of your chair.

    Welcome to the world of Un-geeks.

Thursday, April 20, 2006

Striving to be the best

One of our blog readers asked an interesting question the other day:

“How to be the best” in what you do ?

I guess a cliched answer would be “there is no silver bullet as an answer”. But really, this question interested me, because in work life, so many people approach us saying “they are so busy to do anything else” and that their work life is killing their personal life.

These are what I consider to be the basic tenets of “striving to be the best”. Just like the United Airlines ad. puts it “Where you go in life is upto you. There is one airline that can take you there”, these thoughts can help take you to your goals:

  • Listen – The more you listen, the more you’d learn how little you know. In my field of technology, there are so many smart people doing great things that you are always learning (and I bet that is true for any field). Talk to people, ask for their opinions, let them feel good that they are being asked for advice. They may say twenty things out of which you may not have known one
  • Talk – Any person who has taught before knows this well. If you really want to make sure you understand something, try explaining it to someone else. Put yourself on the block, describe the concept, the thought and open yourself for cross examination.
  • Share – The best way to continuously improve is to share your knowledge, and ask others to share in return. Whatever be the forum – blogs, meetings, informal get-togethers and similar. Sometimes, it amazes me how little people want to share vs. how much they want to talk about what they know.
  • Read – You have to keep reading – read journals, articles, magazines and whatever else you can find related to your line of work. And read a little beyond your line of work too (I can this a lateral activity – you will be amazed how often you can link two domains into a brand new concept)
  • Eat Humble Pie – I have repeated this several times before in previous articles. If there is one thing that is the worst enemy in your quest for being the best, it is your ego. If someone tells you that you are wrong, listen to it with an open mind and analyze the response before you decide to respond.
  • Dive in and look up – As you dive into details and get to understand the guts of what you really need to know, don’t forget to breathe and look up at the bigger picture. Here is something I always do – every once in a while, I draw and end-end network diagram of how what I am reading about could be used end-end. You must keep the overall objective in mind as you dive in and keep asking yourself “How does this work” and “How is is applied ?” and “at the end of the day, who does this benefit?”
  • Passion – The most important tenet. You’ve got to love what you do. If you think what you are doing is a chore, you are already second-best.
Let me open the floor to the readers - what do you think are the basic steps in being the best ?

Thursday, April 13, 2006

3GPP & IMS - How real is it ?

In a previous article, I talked about how SIP itself has evolved into a sphagetti protocol. Now add to that, a complex IMS network and you have more confusion. In addition, you have hundreds of ‘talkers’ who really have no hands-on experience with IMS making confusing and extreme statements like ‘IMS-SIP breaks non IMS-SIP’ , or, ‘Oh ! I just need to plug in my wireline SIP application server to a CSCF and bingo ! We have a system working. Isn’t SIP so great’ ? Both the statements are typically made by people who read a web tutorial on the IMS and make their own conclusions. So I thought it would be nice to put up a small status update on the IMS and 3GPP , as I see it. What is the IMS, really ? IMS is an all-IP based network architecture for the mobile world. The ‘IMS’ is not a new protocol ! Neither is ‘IMS-SIP’ – there is no such thing. Here is how you should look at it: the IMS (IP Multimedia Subsystem) is a network architecture. It uses SIP in addition to a variety of other protocols to specify an architecture that is suitable for use in a mobile deployment. To achieve a mobile deployment network requirement, it may be necessary to ‘extend’ protocols to support certain scenarios that do not apply to other networks (as an example, in the mobile world, you need to worry about going in and out of cell coverage and what that does to your voice call, while this is not an issue with fixed wireline phones). Therefore, IMS had made several extensions to SIP messages and headers and more importantly, have specified procedures that tackle these special scenarios. This is what marketing calls ‘IMS-SIP’. In reality, it is SIP with relevant extensions. This distinction is important – ‘SIP with relevant extensions’ follows the basic RFC 3261 principles of ‘those who do not need to understand these extensions can pass them down/upstream without breaking anything’ while ‘IMS-SIP’ implies it is a fundamentally altered protocol from the perspective of principles. What is the difference between 3GPP and IMS ? This is important. IMS (and SIP) is just one part of 3GPP. 3GPP specifies a multi-level architecture which covers Radio Access, IP Connectivity, Session Management and Services. Out of this, IMS kicks in only for Session Management and Services. Within the IMS, SIP is only one (but important) protocol. There are many other protocols in use for different purposes (authentication, user profile, billing etc.) What are the design goals of 3GPP ? If I were to put it succintly (people say I have a hard time saying anything succintly):
I remember back in 2000s, every show you went to, people had large billboards saying ‘SIP’. At that time, H.323 proponents would make snide comments about ‘Oh it is just a marketing ploy. SIP is too immature. It is just not ready’. And they were right, then. I recently attended CTIA wireless in Vegas, and in 2006, I noticed that 3 lettered acronyms are still favored, but its not SIP. Its ‘IMS’. And this time, ‘wireline SIP vendors’ are making snide comments about ‘Oh it is just a marketing ploy. IMS SIP is too immature. It is just not ready’. And they are right, partially, at least for now. It is all really a cycle. Technology takes time to mature. In a previous

  • Access Independence: The architecture should work over any access (UMTS, CDMA2000, WCDMA etc)

  • Service Independence: The architecture deployed to bring users new services should not be closely tied to the mechanics of the underlying network so that 3rd party application vendors can use the ‘underlying network’ as an ‘SDK’ to build new services. As a corollary, the core IMS network should not need to be aware of the exact service it is executing. This enables scalability at the core and full control at the services layer

  • Strong identity and authentication: Cell phones are used for critical business operations. This is a multi-billion dollar revenue model. Fraud, identity theft, rogue operations and similar is serious business here.

  • Conform to the essential principles of SIP – the IETF has worked very hard with 3GPP to ensure that the usage of SIP is in line with the architectural goals of the protocol.

Has 3GPP succeeded in its goals ? Access Independence: When you start designing a 3G network, you will see that a lot of procedures are repeated. For example, when a phone first switches on, there is encryption and authentication at the radio level. Then, there is authentication at the IP Connectivity level (where your phone gets an IP address). Finally there is authentication again, at the SIP level. When you think about it, the only way to achieve ‘layer independence’ is do not assume that any layer below you will perform any critical functions that you need at your level. While Release 5 of the 3GPP system had some dependencies with GPRS being the access layer, subsequent releases fixed these holes. Today, Release 7 & 8 of the 3GPP/IMS architecture does a good job of access independence. The same architecture can be deployed over a variety of access mechanisms (including WLAN, xDSL etc.) ­Service Independence: If you see how the IMS subsystem of the 3GPP model is architected, they have done a good job of isolating ‘service’ from ‘core’. Any ‘service’ is hosted by an application server, which talks to a ‘core router’ called S-CSCF via SIP. If the application server needs to talk another protocol (like Parlay), then an adaptation gateway is deployed which coverts from Parlay-SIP. The core routers do the job of reaching the messages to and fro without knowing that the message really is for a ‘presence based conference service’ for example. In addition, the entire charging architecture of the IMS is very generic:

  • Several nodes in the IMS are capable of generating CDRs

  • There is a well defined mechanism for the IMS to communicate with the ‘IP Connectivity’ layer to correlate billing records. (For example, if you are doing a voice chat, the IMS level only sees the signalling, while the voice is streamed via a node called the GGSN which is part of the IP Connectivity layer. So how do you ensure that the provider can charge by media content, if required ? You do it by defining a well defined mechanism for different layers to communicate with each other)

Strong Identity and Authentication: 3GPP has detailed procedures for strong identity and authentication. When a device registers, it is securely authenticated and verified at multiple levels, including at Radio level as well as IMS-SIP level. In addition, there is a wonderful concept of associating more than one identity to a user. For example, “Bob” may have bought a subscription from a 3GPP operator, but may want to ‘login’ from his desktop PC or his mobile. Depending on which device he logs in from, certain features may be enabled or disabled (example, his mobile phone may not support wideband codecs). ­Conformity to the basic principles of SIP: This ofcourse is a lofty goal and a continuous target. I have been tracking IMS since release 5, and with every subsequent release, they have inched closer to this goal. There will be certain differences, based on the network in question (for example, IETF would like SIP architectures to be oblivious of the service defined and rely solely on primitives. 3GPP on the other hands wants to ‘specifically identify a service’ so that it is easier to map QoS and priority to the service in question by the operator). Also, by the time a message leaves the core IMS boundary (from the S-CSCF to the AS, for example) several of the proprietary headers are stripped off – and only a few headers remain, which external agents still have to process, but atleast not in the scores ! Are there any issues with 3GPP/IMS ? Of course there are. Specification of an all-IP based system for the mobile world is much harder than for a wireline fixed world. People who think otherwise have probably never designed a mobile network. There are several issues still pending with 3GPP/IMS which have not yet been adressed. For example:

  • All IP emergency handling is still work in progress

  • Mapping of basic supplementary services to an all IP mechanism is still being defined

  • Several interworking situations are not yet addressed (for example, if a user is roaming in a circuit switched network, how does he participate in a PoC session and try to control the floor ? Who maps TBCP to something else ? )

  • User/service provisioning is still somewhat adhoc – even though there is an HSS, most providers use proprietary provisioning mechanisms. Even though 3GPP has a ‘generic user profile’ reccomendation out, very few actually use it.

  • Interworking IMS entities with non IMS entities is only address at a high level. Several details are ‘TBD’ (here is an example: an IMS UE should perform a local ringing alert only when the remote party signifies QoS commit has been approved, via UPDATE. A wireline SIP endpoint will start local ringing the moment it gets an INVITE. In other words, if wireline SIP endpoints do not support this flow negotation, some mediation will have to do it. There are many other nuances)

Conclusion All in all, 3GPP and the IMS archtecture has made great strides in creating a multi-level heirarchy which ensures architecture isolation and distribution as well as offers existing mobile operators a mechanism of protecting their investments. When several ‘p2p’ proponents call out 3GPP as a ‘walled garden’, really, it is an operator who chooses to deploy 3GPP with walled garden administration policies. The architecture, by itself, I believe, is as neat as it could get, considering the challenges it is trying to solve. More often than not, the people I meet are either: a) Wireline folks who have little idea about the mobile world and love to talk about the simplicity of 'migrating to a wireless world' with a simple addition of some 'magical converter' b) Paranoid folks who think the IMS is such a complex beast that it will take eternity and a few more weeks to realize it. The truth, really, is somewhere between the two.

Saturday, April 8, 2006

'Tis the Season of Surcharges & Fees

It's tax season time and it's only appropriate to discuss all things taxes, aka "surcharges" in our industry. I've always believed the incumbents with or without VOIP have a huge pricing power over any emerging technology that mimics what they offer.

Spunky voice providers like Vonage and SunRocket can offer cut-throat prices (aka spend their venture dollars on you and me), but they will never be able to displace the incumbents for basic residential service. Besides, take a look at my all-i-want-is-9-1-1 phone bill below and decide for yourself if at&t or the US Goverment is the competition in my area!

The odds are against them especially when Uncle Sam and his 50 nephews and nieces grab their share of surcharges and fees from you every month. Of course, you cannot call them taxes :-)

And I don't actually use my phone and have the service only for E-9-1-1.

I think the only way to compete is to fight on the access side and the events that are transpiring in the muni networks is the way to go. The fight is still in the pipes.

Voice, after all, is just another application on the network.