Whispers & Screams
And Other Things
Vastly experienced, versatile senior technical asset with a broad range of highly evolved skills from team building to high-level technology solution implementations. A courageous and tenacious leader with proven experience in business development, organisational visioning, cutting edge information technology deployments, and as a senior management liaison. Experienced at working at all levels from Start-up to Corporate, I thrive on change and take the lead to engage and drive the engineering landscape in any business An outgoing personality, with high energy levels who is customer focused but understands the need for a structured approach to business. A mature and collaborative style provides excellent communication and presentation skills and, drawing on past experience, gives the credibility to build trust. A strategic thinker, who is innovative and creative and makes technically 'savvy' decisions and encourages others to do so, whilst totally focused on success and how this drives results.

Get in the back! The robot's driving.

The much vaunted phenomenon of automated cars has returned again to the news this week, Read this here. Events like the DARPA Grand Challenge and their ilk continue however to demonstrate that robots can and probably will develop into the way forward for general purpose motoring and transportation.

The storms in Scotland yesterday saw enormous numbers of vehicles struggling to cope with the adverse conditions and either blowing over or bashing into each other and it probably wont be the last time the winter weather presents challenges to the UK motorist with snow gently falling over our Ayrshire offices again this morning.

These two events show the stark contrast between human and robotic drivers. The simple fact is, well before the end of the next decade, humans will be relegated from the drivers seat into the passenger seats. Ok perhaps not all vehicles will conform to this model. Some vehicles will still allow a human to sit behind the wheel, but only with a vigilant robot “supervisor” who will watch their every move and silently fix the human mistakes whilst simoultaneously scanning for unforeseen hazards. Driving a car as we do today will become a risky hobby which will only be possible on specially designed closed courses.

You think this sounds far fetched? Its no less far fetched however than the notion that humans could be trusted behind the wheel of a vehicle in the first place. Henry Ford would look at todays vehicles with incredulity if he did so in the context of the annual death toll on our UK roads which stood at over 2000 last year. The simple fact is we are terrible drivers and getting steadily worse as technology inside and outside vehicles demands more and more from us. The modern car is probably comparable in complexity of systems to a fighter jet of only a few decades ago.

Couple this with the fact that we are often just plain stupid, our eyesight is poor, our hearing suspect even if we choose not to be blasting the latest hits on our car stereos and we lack any appreciation at all of Newtonian physics, blindly tailgating at 80mph in rush hour traffic. Theres no escaping the fact that judgment is evident on the roads only by its absence. In stark contrast, robot drivers can be programmed with the most vulcan style logic coupled with sensory powers that put the human driver to shame.

The robots in the DARPA Grand Challenge could be easily programmed with the full highway code and could sense distances to within a millimetre in the daylight, in fog or even in the dark They could see in the dark and through the sort of fog that would blind any human driver. These robots are but the first members of a class of devices that will advance along a steep curve like that traced by computers and the Internet over the last two decades and will ultimately seem as old hat as a Sinclair ZX Spectrum in a few short years.

Its important however to bear in mind that filling the UK's roads with robot controlled vehicles is about much more than road safety. The introduction of such capable vehicle control could enable the virtual elimination of traffic congestion by safely increasing the density of vehicles per mile by an order of magnitude. They could also eliminate the need for traffic lights, by having robot controlled vehicles safely nip through the gaps in the crossflow traffic rather than waste time waiting for green lights.

Robotic vehicles could also turn commutes into productive time enabling the human passengers to sit back and catch up on work, watch TV, access the net or even sleep. Indeed it would no longer be a necessity to be able to drive in the first place to make use of the road traffic networks enabling the very young or the very old to get from A to B. Imagine no more school runs or newly qualified driver deaths due to inexperience or worse. One thing is certain though. This prediction will seem ever so quaint in a few years as the whole model of how we move around will be rewritten in ways we cannot yet imagine by the introduction of automated transport. The advent of automated transport is as profound a change as the arrival of the horseless carriage 100 or more years ago and the impact on global society today is no less unpredictable.

Think about how our town centres will look in a world where no car parks are necessary. Nowadays, car parks need to be close to the places we need to get to such as workplaces, out of town shopping areas and town centres however in a world of automated transport, car parks could be anywhere, perhaps miles outside of the areas we needed to get to in the first place and can also store vehicles with far greater density since the whole system will be controlled by the system.

The most significant difference however is probably that in a world of automated transport, fewer people will need to own cars at all, relying instead on fleets of shared vehicles.

It certainly is strange to think of our great grandchildren marvelling at the 2009 KIA C'eed in a museum and looking with wonder at the old pictures of what used to be the M25 whilst listening to the Road to Hell by Chris Rea. They will probably wonder how we ever managed to cope with being trusted with a couple of tons of fuel injected steel.
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Best definition of the labour party I ever saw..

INEPTOCRACY - A DEFINITION

Ineptocracy (in-ep-toc’-ra-cy) - a system of government where the least capable to lead are elected by the least capable of producing, and where the members of society least likely to sustain themselves or succeed, are rewarded with goods and services paid for by the confiscated wealth of a diminishing number of producers.
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Coming back to life

Where were you when I was burned and broken
While the days slipped by from my window watching
And where were you when I was hurt and I was helpless
Because the things you say and the things you do surround me
While you were hanging yourself on someone else's words
Dying to believe in what you heard
I was staring straight into the shining sun

Lost in thought and lost in time
While the seeds of life and the seeds of change were planted
Outside the rain fell dark and slow
While I pondered on this dangerous but irresistible pastime

I took a heavenly ride through our silence
I knew the moment had arrived
For killing the past and coming back to life

I took a heavenly ride through our silence
I knew the waiting had begun
And I headed straight..into the shining sun.
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Alone

From childhood’s hour I have not been
As others were—I have not seen
As others saw—I could not bring
My passions from a common spring—
From the same source I have not taken
My sorrow—I could not awaken
My heart to joy at the same tone—
And all I lov’d—I lov’d alone—
Then—in my childhood—in the dawn
Of a most stormy life—was drawn
From ev’ry depth of good and ill
The mystery which binds me still—
From the torrent, or the fountain—
From the red cliff of the mountain—
From the sun that ’round me roll’d
In its autumn tint of gold—
From the lightning in the sky
As it pass’d me flying by—
From the thunder, and the storm—
And the cloud that took the form
(When the rest of Heaven was blue)
Of a demon in my view—
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The EIGRP (Enhanced Interior Gateway Routing Protocol) metric

EIGRP (Enhanced Interior Gateway Routing Protocol) is a network protocol that lets routers exchange information more efficiently than was the case with older routing protocols. EIGRP which is a proprietary protocol evolved from IGRP (Interior Gateway Routing Protocol) and routers using either EIGRP and IGRP can interoperate because the metric (criteria used for selecting a route) used with one protocol can be translated into the metrics of the other protocol. It is this metric which we will examine in more detail.

Using EIGRP, a router keeps a copy of its neighbour’s routing tables. If it can’t find a route to a destination in one of these tables, it queries its neighbours for a route and they in turn query their neighbours until a route is found. When a routing table entry changes in one of the routers, it notifies its neighbours of the change. To keep all routers aware of the state of neighbours, each router sends out a periodic “hello” packet. A router from which no “hello” packet has been received in a certain period of time is assumed to be inoperative.

EIGRP uses the Diffusing-Update Algorithm (DUAL) to determine the most efficient (least cost) route to a destination. A DUAL finite state machine contains decision information used by the algorithm to determine the least-cost route (which considers distance and whether a destination path is loop-free).

Figure 1




The Diffusing Update Algorithm (DUAL) is a modification of the way distance-vector routing typically works that allows the router to identify loop free failover paths.  This concept is easier to grasp if you imagine it geographically. Consider the map of the UK midlands shown in Figure1. The numbers show approximate travel distance, in miles. Imagine that you live in Glasgow. From Glasgow, you need to determine the best path to Hull. Imagine that each of Glasgow’s neighbours advertises a path to Hull. Each neighbour advertises its cost (travel distance) to get to Hull. The cost from the neighbour to the destination is called the advertised distance. The cost from Glasgow itself is called the feasible distance.
In this example, Newcastle reports that if Glasgow routed to Hull through Newcastle, the total cost (feasible distance) is 302 miles, and that the remaining cost once the traffic gets to Newcastle is only 141 miles. Table1 shows distances reported from Glasgow to Hull going through each of Glasgow’s neighbours.

Table 1




Glasgow will select the route with the lowest feasible distance which is the path through Newcastle.

If the Glasgow-Newcastle road were to be closed, Glasgow knows it may fail over to Carlisle without creating a loop. Notice that the distance from Carlisle to Hull (211 miles) is less than the distance from Glasgow to Hull (302 miles). Because Carlisle is closer to Hull, routing through Hull does not involve driving to Carlisle and then driving back to Glasgow (as it would for Ayr). Carlisle is a guaranteed loop free path.

The idea that a path through a neighbour is loop free if the neighbour is closer is called the feasibility requirement and can be restated as "using a path where the neighbour's advertised distance is less than our feasible distance will not result in a loop."

The neighbour with the best path is referred to as the successor. Neighbours that meet the feasibility requirement are called feasible successors. In emergencies, EIGRP understands that using feasible successors will not cause a routing loop and instantly switches to the backup paths.

Notice that Ayr is not a feasible successor. Ayr's AD (337) is higher than Newcastle's FD (302). For all we know, driving to Hull through Ayr involves driving from Glasgow to Ayr, then turning around and driving back to Glasgow before continuing on to Hull (in fact, it does). Ayr will still be queried if the best path is lost and no feasible successors are available because potentially there could be a path that way; however, paths that do not
meet the feasibility requirement will not be inserted into the routing table without careful consideration.

EIGRP uses a sophisticated metric that considers bandwidth, load, reliability and delay. That metric is:




[latex]256, *, left(K_1, *, bandwidth ,+, dfrac {K_2 ,*, bandwidth}{256 - load}, +, K_3 ,*, delayright), *,dfrac {K_5}{reliability ,+, K_4}[/latex]


Although this equation looks intimidating, a little work will help you understand the maths and the impact the metric has on route selection.

You first need to understand that EIGRP selects path based on the fastest path. To do that it uses K-values to balance bandwidth and delay. The K-values are constants that are used to adjust the relative contribution of the various parameters to the total metric. In other words, if you wanted delay to be much more relatively important than bandwidth, you might set K3 to a much larger number.

You next need to understand the variables:

    • Bandwidth—Bandwidth is defined as (100 000 000 / slowest link in the path) kbps. Because routing protocols select the lowest metric, inverting the bandwidth (using it as the divisor) makes faster paths have lower costs.

 

    • Load and reliability—Load and reliability are 8-bit calculated values based on the performance of the link. Both are multiplied by a zero K-value, so neither is used.

 

    • Delay—Delay is a constant value on every interface type, and is stored in terms of microseconds. For example, serial links have a delay of 20,000 microseconds and Ethernet lines have a delay of 1000 microseconds. EIGRP uses the sum of all delays along the path, in tens of microseconds.



By default, K1=K3=1 and K2=K4=K5=0. Those who followed the maths will note that when K5=0 the metric is always zero. Because this is not useful, EIGRP simply ignores everything outside the parentheses. Therefore, given the default K-values the equation becomes:




[latex]256, *, left(1, *, bandwidth ,+, dfrac {0 ,*, bandwidth}{256 - load}, +, 1 ,*, delayright), *,dfrac {0}{reliability ,+, 0}[/latex]


Substituting the earlier description of variables, the equation becomes 100,000,000 divided by the chokepoint bandwidth plus the sum of the delays:




[latex]256, *, left(dfrac {10^7}{min(bandwidth)}, +,sum,dfrac {delays}{10}right)[/latex]


As a final note, it is important to remember that routers running EIGRP will not become neighbours unless they share K-values. That said however you really should not change the K-values from the default without a compelling reason.

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