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Das Blog zu IT, Mobilfunk & Internet

Eine kleine Übersicht der DSL Anbieter

Januar 3, 2008 von Harald Puhl

Der DSL Markt im Wandel
Wer ein passendes DSL Angebot für sich sucht, sollte den DSL Markt in Deutschland ein wenig kennen. Und, um den deutschen DSL Markt zu kennen, sollten man wiederum einiges über die DSL Anbieter auf diesem Markt wissen. Es gibt derer viele, die potenziellen Kunden DSL Angebote offerieren und um Marktanteile kämpfen. Allen voran die Telekom als größter DSL Anbieter mit ihren Marken T-Home DSL und Congstar DSL. Fünf bis sechs DSL Anbieter folgen und haben Ihre Strategien in letzter Zeit geändert. Es könnte spannend werden.

Nichts geht über Telekom. Das ist jetzt nicht als qualitative Wertung gemeint. Aber die Telekom ist einfach mit Abstand größter DSL Anbieter auf dem deutschen Markt. Ihr DSL Netz ist deutschlandweit am besten ausgebaut, war lange Zeit das einzige DSL Netz hierzulande. Inzwischen erreicht dieses Netz über 90% alle Deutschen, die über das Telekom – Netz einen DSL Anschluss erhalten können. Die Telekom hat sich als DSL Anbieter mit ihrer Marke T-Home DSL etabliert. Da die jedoch den Ruf hat, zwar ganz gut, aber relativ teuer zu sein, kreierte die Telekom eine weitere Marke: Congstar DSL — mit ihr sollen sehr preisbewusste Zielgruppen erreicht werden. Der Marktanteil der Telekom als DSL Anbieter liegt bei knapp 50%.

Hinter dem DSL Anbieter Telekom… kommt lange Zeit nichts, betrachtet man die Marktanteile. Die größten Verfolger heißen heute 1&1 von United Internet, Arcor und Alice von Hansenet. Ihre Marktanteile lagen Ende September 2007 zwischen 12% und 15%. Lange Zeit konnten die anderen DSL Anbieter neben der Telekom nur auf das Telekom DSL Netz setzen, weil sie nicht oder kaum eigene DSL Netze besaßen. Sie traten dann als DSL Resale Anbieter auf. Das bedeutet: Ihre Kunden behielten ihre Telekom-Telefonanschlüsse, bekamen den DSL Anschluss — der das DSL Netz der Telekom nutzte — aber vom jeweiligen Nicht-Telekom-Anbieter. Verträge mit der Telekom machten das möglich. Die Zeiten sind anders geworden. Heute bauen die meisten DSL Anbieter eigene DSL Netze auf und werden dadurch zunehmend unabhängiger von der Telekom. Sie bieten nun DSL Komplettpakete an, also sowohl Telefon- als auch DSL Anschluss in einem Paket. Das stärkt sie in der Konkurrenz zum Marktführer auf dem DSL Markt. Die Zukunft dürfte spannend werden, wenn es um kommende Marktanteile der DSL Anbieter in Deutschland geht.

A discussion of image resolution

Dezember 18, 2007 von Harald Puhl

Resolution is a term that expresses how well the graphic presentation shows the spatial details in a picture. It is a measure of the fineness of the picture elements. Digital images consist of a large number of picture elements (pixels) in rows and columns, each with a defined color. A pixel is one of many cells that form a picture. An image may extend X pixels from left to right and Y pixels from top to bottom, and contain X times Y pixels. A user has some latitude in how many pixels are used to display a certain picture. For example, the monitor has a few settings for selecting the full screen presentation. The most commonly used resolution setting is 800 X 600 pixels. If every pixel is actually seen (including the corners of the image), there will be 480,000 of them.
Modern digital cameras have frame sizes of 2 megapixels or 4 megapixels, so the need to re-size and crop these images becomes important. If a full-frame image is received as an attachment, the recipient may see only the upper-left corner of the image unless they do some scrolling. Then they may like to make the picture small enough so that it is more readily viewable without scrolling.
Re-sizing and cropping are topics discussed later.
Most viewing software applications (and printers) display the typical image formats BMP, JPG, and GIF at 96 pixels per lineal inch. If a user wishes to stretch a given image file for presentation or for printing, they will get no better resolution by zooming in to make the image bigger. If an image file is modified by stretching or shrinking the overall dimensions, the software must find a means for making the picture information accommodate a newly formed matrix of pixel sizes or pixel count. If the pixel count changes, the picture must retain its basic character, yet the color assignments of the new set of pixels is not the same as the original picture. The software must have algorithms that account for these requirements. The ability of software to accommodate these zoom requirements varies from one software package to another. A test of the quality of image-modifying software is to note if there is significant degradation of an image if it undergoes a series of changes. One of the more noticeable degradations due to zooming will appear in the quality of the text. A particular font type and size will have specific pixel cells blackened.
If you depart from the resolution in which the text was acquired, some software will have a tough time keeping the boundaries between black and white organized so the stroke width and precise shape of the text characters are maintained or simulated. A zoom-type feature may be used in the MS Paint application by commanding Image|Stretch/Skew. When the Stretch and Skew dialog box appears, you will note that there are small highlighted windows opposite the words Horizontal and Vertical in the upper (Stretch) panel which each say 100%. To shrink the picture to half of the original image dimensions, you do so in two steps.
First, click (dropping a cursor) in the Horizontal (small) window, and replace the 100% with 50 %, and click on Okay.
Then do the same for the 100% value in the Vertical (small) window, and click on Okay.
Scanner software generally has choices of scan resolution, as well as black and white vs. color, and a further determination of gray scale or simply black OR white coding when choosing black and white. The latter distinction is important when choosing whether you need two levels (one bit) of gray (either black OR white) or many levels (gray scale), which affords a more accurate rendition of the source material. Most often, you will find that the scanner software offers about five default settings for making these selections, and the means for making custom settings which depart from the default values. A large picture will produce a large image file, and settings that provide more picture details will make that file even bigger. The temporary image format used in scanner software and in image conversion software has no compression (i.e., all picture information is defined within each presented pixel). Thus, the user should note that it takes time for a slow computer to compile all the necessary data to form and to reformat this image if an unusually large, detailed image is being used. In fact, users should be aware that limitations of computer processing speed may not be apparent until you use large media files like a large color photos with high resolution. A user should be judicious in the choice of the scanner settings to make an image file having suitable spatial resolution and color resolution (the fineness of allowed step changes in the color palette) so that the selected resources are appropriate for the end result. Another image format is available that provides for more than 96 dpi resolution. Although the scanner software can accommodate resolutions that exceed 300 dpi, the user may wish to transfer that file to another computer which doesnt have the same scanner software. The format most often used for this purpose is TIF or TIFF. The TIF format provides for resolutions of 300 dpi, or other values which may be set when encoding the file. Also, it will encode either as uncompressed or compressed (JPG and LZW are compression options). The software application needed for creating a TIF file is (Kodak) Imaging, which is automatically installed with modern versions of Windows. Like MS Paint, Imaging will accept images from a clipboard, but you must define the spatial resolution and the color depth unless you are willing to accept the default settings. Imaging can be used for pictures of higher resolution than MS Paint, as it supports spatial resolutions greater than 96 dpi.
A user can copy or export scanned high-resolution images to JPG , GIF, or BMP formats, but the picture dimensions will increase to match the defined 96 dpi for these formats. If images are exported into TIFF format in Imaging with a resolution that matches that of the image exported from the scanner software, the dimensions wont change. The JPG and GIF formats have become standards for use on the internet, as they are able to reduce file sizes while preserving picture details. This is accomplished with the use of sophisticated algorithms that make choices about the picture elements (pixels) whose color definition dont change from the one which precedes it in the defined sequence of forming the pixels into the file.
In this sense, the algorithm votes out the data associated with certain pixels if there is no change from its preceding neighbor. In the viewer software, its algorithm has the ability to reformulate the original image in the absence of the data for those pixels whose color data was voted out. Also, web browsers will present files in JPG and GIF formats, while many web browsers may not present some of the other formats.
JPG file creation depends on a quality selection, often made by the user, in which the user makes a trade-off between the requirements for retaining image quality, and the resultant file size. Thus, a user can make a file with less than 100% quality retention if a smaller file size is desired. A JPG file is most often selected if the picture contains subtle shadings of color, and a small file size is desired. A JPG quality factor of 70% is often acceptable, as it represents a good trade-off between picture quality and file size. A GIF file is often chosen for tables, figures, cartoons, clip art, etc., where few shades of color are present. Choosing the GIF format for this kind of picture often results in a smaller file than a JPG file would provide. GIF is often used for the collection of small image insets which are placed on a web page. If a GIF file of appreciable dimension is shown in the top half of a web home page (so a visitor will see the image form on their screen), the visitor may notice that this image forms in a way which may seem distracting, since the picture elements form in cells much bigger than a single pixel, and these cells become progressively smaller as the fully resolved image takes form. This effect usually is not noted in GIF files of small dimension.

DSL Flatrate und Telefon Flatrate

Dezember 2, 2007 von Harald Puhl

DSL (Digital Subscriber Line) sorgt für einen schnellen Internet-Zugang über ein Telefonnetz. Im Vergleich mit Internetanschlüssen über ISDN oder ein Telefonmodem liegen die Datenübertragungraten um ein Vielfaches höher, wofür bislang nicht genutzte Frequenzen des vorhandenen Telefonnetzes sorgen.

Schnell, schneller, am schnellesten: Seit der Einführung von DSL in Deutschland hat sich die DSL Geschwindigkeit kontinuierlich erhöht. Galt zu Beginn der DSL-Ära ein DSL Anschluss mit 768 Kilobyte in der Sekunde als das Maß aller Dinge, so ist mittlerweile DSL 6000 der Standard-Anschluss und auch DSL 16000 bereits vielerorts verfügbar. Ausschlaggebend für diese Expansion ist die Weiterentwicklung der Breitbandtechnologie ADSL.

Im Zuge dieser Geschwindigkeitserweiterung erhöht sich auch die Zahl der Anwendungen, die im Internet durchgeführt werden können: Internet-TV, aufwendige Online Games und Video-on-Demand machen den Rechner zur Multimedia-Zentrale. Immer mehr User verschaffen sich deshalb eine DSL Flatrate, mit der sie zum monatlichen Festpreis alle laufenden Internetkosten abdecken. Auf Grund der steigenden Nachfrage bieten DSL Provider ihre Flatrate Tarife mittlerweile zu sehr günstigen Preisen an. In der Regel bekommt man eine DSL Flatrate für weniger als zehn Euro.

Auch DSL Telefonie lässt sich über eine monatliche Pauschale abwickeln. Mit einer Telefon Flatrate führt man Tag für Tag kostenlose Gespräche ins deutsche Festnetz – dabei ist sie ebenso preiswert wie eine DSL Flatrate. Volumen- oder Zeittarife, bis vor kurzem noch akzeptabele Tarif-Option, verursachen bei täglicher Internet-Nutzung inzwischen erheblich höhere Kosten als DSL Flatrate Angebote. Deshalb gilt: Am Günstigsten fährt man derzeit mit einer Doppelflatrate.

What is the point of unlimited data in mobile networks?

November 29, 2007 von Harald Puhl

One has to wonder, when you read news like this, where Orange France is stating that their 500MB per month data plan, tied to the iPhone, excludes pretty much everything other than email and web browsing. So no VoIP, modem access for your laptop, or even newsgroups (??).

In Spain, Vodafone has been toting 5GB/month plans for some time now, with similar “fair use” policies. What is exactly the point of having such huge data plans, when all you can do is squint at the web on a tiny screen, or read your email – without trying to open attachments which are even harder to read. Granted, the iPhone has represented a leap in usability on these two fields, with fantastic web browsing, and very usable email where attachments can at least be useful. The only problem is the iPhone is one device lacking many functionality other platforms already enjoy, such as VoIP, decent IM, and…newsgroup access. These will come for sure, only because there is a very dedicated community of hackers porting and writing applications for it.

During my first month of iPhone use, when the novelty wants to make you try everything and, for example, browse the web when you don’t really need to, but just because it’s so cool – I went through about 70MB of data. Peanuts, compared to the 1GB plan I had with Vodafone…

Facebook – a short tail ad system

November 11, 2007 von Harald Puhl

When I started reading some interesting articles about Facebook’s new ad system, which is supposed to combine what your friends are doing, buying and recommending, with the available ad content, my first thought aside from the spying-on-users issue was “How are they going to get the little guys on board this thing?”.

Let me explain: CocaCola doesn’t really -need- to advertise on Facebook, as it’s one (if not the most) recognized brands on the planet. Still, it has created this animated Sprite Sips Facebook application, which you can “boost” with codes found under Sprite bottle caps. The app will most likey be installed by a large number of people, basically, because it comes from a well-recognized brand which is also regarded as cool, many of which already drink the stuff on a regular basis.

What is happening is that users are marketing to other users with well-known products – but would they do the same with, say, ‘BoogieCola’? This imaginary company may be desperate to market its product as much as it can, having just launched into an already crowded space, with a product that may not be so nice and with a brand image which could be the result of the CEO’s 5-year-old son’s doodling on a paper. In other platforms, they could buy their way into the top advertising spots (read: Google AdWords), and make an impact across a wide population segment. While not a guarantee of success, at least you will not be able to say you failed because nobody knew you existed. On Facebook, this company would have probably gone largely ignored – as the ads targeted to users would probably point to the already-know, already-heavily-recommended brand. Thus, it will be pretty hard for newcomers to make Facebook an effective platform for entry into a market. In the end, the (OMG I’ve said it, I will burn in hell!) long tail of advertisers, who provide a sizable chunk of Google’s revenue, will not be sending their bucks to Facebook.

Could this new system make substantial revenue for Facebook? I guess so – but not in the long term, and most definitely not enough to even consider taking Google out of the picture. Google is omnipresent in many countries and market segments, while Facebook has had an impact basically in the US, a large market by itself, but again, not as big as the one the Big G has access to.

Facebook is going to start tracking you on 44 sites…so what?

November 7, 2007 von Harald Puhl

Google is already tracking you on millions of sites, thanks to this little piece of code:

<script src=”http://www.google-analytics.com/urchin.js” type=”text/javascript”>
</script>
<script type=”text/javascript”>
_uacct=”UA-xxxx-x”;
urchinTracker();
</script>

Do you use GMail? Well, Google is scanning the contents of all your messages, and they also log the IP address you use to check your email – thus, they can tie all your browsing habits to your individual email account and the content of your emails. This is a huge amount of information for any company to gather about individuals. Additionally, Google keeps records of the searches you perform on their engine, thus giving them yet another layer of data to check. Scared yet?

In contrast, Facebook announced that they will be launching a targeted advertising platform with 44 partner sites, which will add a tracking code informing Facebook of your browsing habits. More by Om Malik here. I personally don’t care about 44 sites, but about the millions of sites using Google Analytics, and about the people using GMail to check their corporate email accounts, thus potentially having sensitive material indexed by Google. Food for thought.

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