So we have discussed the use of a single transport mechanism for all forms of communications and how that, in of itself, has advantages and disadvantages. I have also stated that Convergence is about a lot more than just VoIP, so where else can we converge above with cable and with LAN/WAN?

 

Call Control in a traditional PBX was hidden deep within the giant cabinets on processors running embedded code programs. The operating system for these processors are typically stripped down UNIX derivatives such as WindRiver's VXWorks. The beauty of these operating systems is that they do so little; they do not need to support a large array of applications as you would typically expect to see for a commercial server or workstation OS such as Windows, Linux or Mac OS X. This lack of flexibility allows the number of states and state changes that the application can incur to be finite and can be very precisely tested; this gives rise to highly reliable operation. Embedded code operating systems also tend to be hardware specific and so embedded code processors do not experience the continuous performance increases that you would typically experience in a sever or workstation; embedded code processors tend to stay stable for years and even decades. When processors can no longer be manufactured, the cost to the embedded product developer can be huge and product stability can be affected. The result of this is that the product developers have to be very efficient in the use of these resources and very precise in the impact of new code on resource utilisation. Some of the quirks of the function of devices such as the commercial PBX extension are derived from the need for engineering efficiency. 

 

The emergence of server based call controllers, most notably Cisco's Call Manager, changed the philosophy of how communications systems could be designed. Rather than limiting the functionality to suit the static nature of the hardware, servers enable far greater extensibility of functions and can use the inherent ability of servers to recover from failures through methods such as clustering. When Cisco first launched Call Manager the philosophy was that a server would be much cheaper than the large cabinets full of proprietary hardware and so they would be able to produce a cheaper, more functional phone system. A recurring theme in the Convergence debate is the trade off between increased functionality and reduced reliability. In the early releases of Call Manager, extensibility - the ability to extend functionality - did not equate to a better user experience. Where Cisco miss-estimated the value of the product is in the many years of development that had gone into the development of the PBX user interface; they simply got some basic features of the phone wrong. Whilst the user interface of the phone is far from perfect, it is something that people have grown used to over many years and so can now use intuitively. Given that VoIP was a relatively emerging technology at the time, Call Manager suffered user dissatisfaction as well as reliability problems. Call Manager did succeed where engineers appreciated the potential of the product and it's ability to deploy in a converged environment.

 

The reaction by the incumbent PBX providers to the emergence of server based products was to develop hybrid and dual technology (both TDM and VoIP) solutions. In the same way that Cisco marketed heavily to IP technologists in the elegence of their solution and denigrated the differences is user interface, the traditional PBX vendors used these hybrid solutions to show that they were capable of producing IP, server based solutions. In reality, the majority of the early hybrid solutions were 'marchitecture'; design for brochures and not for deployment. They were technically inelegant, ineffective and unreliable. The mistakes that Cisco made with the user interface and these hybrid solutions gave the PBX vendors enough of an opportunity to reconsider their product development strategies. With Cisco clearly improving the quality of their products, the PBX vendors could not afford to develop software that must run and be reliable on two hardware platforms and so they rapidly stopped software development for the embedded code switches and, soon after, began to end-of-life (EOL) the embedded code processors. This competitive process rather than any genuine user value proposition is what has driven the development of converged communication solutions to it's present position.

Voice over Internet Protocol or VoIP has been one of the most talked about technology changes of the last decade, so what is all the fuss about? Ask the man on the street (and my brother) and he will probably tell you that VoIP saves you money. This can be true but isn't as simple as it sounds:

 

Breaking a voice call into packets requires a header for each packet and so adds overhead, which equals bandwidth, and so for a single call you need more bandwidth for VoIP than TDM. One myth busted: VoIP doesn't use less bandwidth it tends to use more aggressive compression protocols simply because they need to and TDM networks don't. However, there are ways of winning this bandwidth back: People don't tend to both talk at the same time in a single conversation - except in New York - so this bandwidth, nailed up and of no use in TDM (Time Division Multiplexing or digital voice), is available in VoIP. You also don't have to send packets when you are not talking, by using techniques like Voice Activity Detection (VAD), however this is not a totally effective technology as it is imprecise as to when you should stop sending packets and then start again; known as 'shoot/don't shoot syndrome - shout 'don't shoot' and I don't send the first word.......

 

The bigger and more converged the environment, the more effective VoIP becomes. One of the best consultants I have ever worked with, Diane Halliwell, happens to be a traffic expert in her spare time. Her favorite traffic truism is 'The more traffic you throw at it, the more efficient it gets'. So if I can converge all my traffic on to one network it will be more efficient? Absolutely; the first and most aggressive adopters of VoIP were the long distance carriers where they have massive amounts of traffic of all types; so score a win for VoIP there; you have been using VoIP for a lot longer than you knew. Where VoIP also really scores is in the deployment of new home voice services. Vonage and Skype would not have got anywhere if they need to build a network especially in the last mile, instead they use the fact that you are paying someone else for Internet access over that network and you don't mind paying them to ride it - I sense a later blog entry on the business case for carriers forming.

 

But I am an Enterprise Management Consultant so this is of little interest to me professionally. In the Enterprise the value proposition is different; higher value users and lower tolerance for down time. My traditional PBX uses one cable for the phone and a separate one for LAN; avid readers of this blog will leap to the last entry and note that this is use of physical convergence and so is a cost saving. Sorry not really: Single cable = single point of failure. As this is only a relatively small cost saving; many enterprise users of VoIP still use separate cables to the desk-top. I also am taking on an additional cost as I used to have a home run cable and now I have to put LAN electronics on the cable. In addition, TDM PBX's run - and look for that matter - like refrigerators; LANs suffer from far greater reliability problems for a variety of reasons; more on that in later blogs.

 

So an in an enterprise environment, I take a very reliable product and make it less reliable for a greater expense....with little or no feature increase? Actually yes, that's about the size of it; read back, I said that VoIP is one of the most challenging and least rewarding areas of convergence.

 

So why do people do it? There are really two reasons: 1. IP Telephony is much more than just convergence in the transport and 2. you can't buy TDM PBXs any more. Intrigued? Want to know more? Keep logging in friends, I will deliver more gems on IP Telephony in the next entry.

Everyone knows what Convergence is - it is putting voice traffic over data networks (otherwise known as VoIP or IP Telephony) right? Well yes, that is an example of converging at a certain layer but this is actually one of the most difficult and least rewarding value propositions of Convergence. The true value proposition of Convergence is the better utilization of any resource at any layer.

 

So what on earth am I talking about? Let's look at some examples of where Convergence has succeeded and where it has most potential. This will be a series of postings to keep you trembling with suspense (if you want the whole story then hire me!):

 

Physical - at the physical layer Convergence has happened and has had a dramatic impact. Within a premise, structured or Category n cabling is now used for all forms of connectivity for horizontal distribution. Similarly, fiber or structured cabling for the vertical. Those of us that are old enough will remember the fun of providing application specific cable - where every type of terminal and service had a different type of cable required. The effective design of the cabling environment was one of the most important aspects of the design of an IT infrastructure as the cost of mistakes was enormous and could literally render a building unusable. In a volatile environment, within a number of years it could be easier to move and start all over than to continue to pull more and more cable. The advent of Convergence has made the design of the cable infrastructure a lower value; overly simplified, in a Converged cable environment, if you have a power outlet then stick a low voltage outlet next to it; the design of cable plant now requires a lower skill set to design and has removed the risk of a bad design.

 

In the wide area, high speed optical networks now carry all forms of communications; primarily in TDM based SONET networks but Ethernet over glass in Metropolitan Area Networks (MANs) are becoming increasingly effective as all traffic becomes packet based - I will get to this in later posts. This contrasts with direct point-to-point copper cables per service, with the associated capital cost of the infrastructure as well as the cost of maintaining the massive number of physical links.

I see more and more people describing themselves as technology evangelists.

 

As an IT consultant I undoubtably have enthusiasm for technology, however, as a Management Consultant my enthusiasm is for the potential for technology to impact the business for a client. For someone to be evangelical about a technology implies it is the technology in itself that excites them. For technology to have value then it must have a positive impact; for business this must pass my sniff test of three criteria:

If a technology can significantly achieve all three goals then it certainly gets my enthusastic backing. I guess I could be a technology value proposition evangelist but that doesn't really have the same ring to it does it?!

Welcome to the Blog section of the Gregory Collins LLC website.

 

I have given a lot of thought to this web site in the first year of Gregory Collins LLC. Obviously a web site has to express what a company does and so I have put together some static pages giving an overview of some of the services we can provide and our core values. However, I am sure the seasoned observer can see much similarity with other web sites within the sphere of IT consulting; the quality of a company is often not directly proportional to the quality of the web site. So I have decided to link my business blog as have many other companies.

 

The true value of a business blog is to give a less static insight into what makes a company, and it's management, tick. If I attempted to put all my thoughts on every subject down in one go then the company would probably never do any work and the web site would definitiely never get launched.

 

I hope this content is useful and thought provoking. Those that know me and have worked with me will know that I am not short of opinions and not shy in expressing them; they also know that I welcome and embrace constructive critisism so feel free to let me know what you think.

 

Thanks and again welcome

 

Greg