The Hidden Price

3 05 2014

All the cool convenience of our smartphones, tablets, computers, and Internet-based services come with a hidden price – POWER.

And there is more …
critical materials, missing application of recycling technologies in many countries, and missing law enforcement or code of conducts regarding fair labor.

Beside Apple’s ecosystem there is a much greater and more important one, our planet. In April 2014 scientists stated that parts of China are no longer suitable as a habitat for human beings, animals, and plants because of a tremendous pollution load in the air, the water, and the soil.

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As seen from the perspective of physics excessive power used by machines always goes along with excessive generation of heat. So it’s obvious that we pay the price for cooling down the powerful equipment needed for communication and unlimited access to sources of information.

On January 27, 2014, the Department of Ecology’s Air Quality Program received a Notice of Construction application (air permit application) from the Microsoft Corporation proposing to construct and operate the Oxford Data Center in Quincy, Washington. Microsoft has applied for an air permit because the proposed data center would install 36 2.5 MW emergency back-up diesel engine generators, one 0.75-MW emergency back-up diesel engine generator, and 32 cooling towers.

The projected build up of new data center electric loads led directly to forecast increases in energy-related air pollution, both globally and locally.
Greenhouse gas (GHG) emissions such as carbon dioxide from fossil fuel-fired electric generators are a major cause of global climate change. The forecast increases in data center electric demand implied a growing source of GHG emissions. This is cause for concern. The international community is attempting to reduce GHG emissions amid broad scientific and international consensus that climate change is a major threat and must be taken seriously.
Air pollution from diesel generators causes environmental health problems. Each planned data center includes as many as two or more times redundant backup diesel generator capacity, to use when the electric grid is unstable or unavailable. Diesel generators used for emergency backup power supply are essentially unregulated. They are a notorious source of very high levels of damaging air pollutants, including soot, nitrogen oxides (NOx), which form ground level ozone (smog) during hot sunny weather, and others. Coincidentally, the electric grid is most unstable and at risk of failing during hot periods of peak air conditioning demand.

What are data centers?

A data center is a facility used to house computer systems and associated components, such as telecommunications and storage systems. It generally includes redundant or backup power supplies, redundant data communications connections, environmental controls (e.g., air conditioning, fire suppression) and various security devices. Large data centers are industrial scale operations using as much electricity as a small town and sometimes are a significant source of air pollution in the form of diesel exhaust.

Tens of thousands of data centers that now exist support the overall explosion of digital information. Stupendous amounts of data are set in motion each day with an innocuous click or tap.

According to Emerson Network Power 509,147 data centers worldwide were operated in 2011. I didn’t find updated information but it’s obvious that we have a lot more today because of the gaining popularity of mobile devices.

Most data centers, by design, consume vast amounts of energy in an incongruously wasteful manner, interviews and documents show. Online companies typically run their facilities at maximum capacity around the clock ensuring 99.99% availability, whatever the demand is. As a result, data centers can waste 90 percent or more of the electricity they pull off the grid. In Silicon Valley, many data centers appear on the state government’s Toxic Air Contaminant Inventory, a roster of the area’s top stationary diesel polluters.

Worldwide, the digital warehouses use about 30 billion watts of electricity, roughly equivalent to the output of 30 nuclear power plants, according to estimates industry experts compiled for The New York Times. Data centers in the United States account for one-quarter to one-third of that load, the estimates show.

“It’s staggering for most people, even people in the industry, to understand the numbers, the sheer size of these systems,” said Peter Gross, who helped design hundreds of data centers. “A single data center can take more power than a medium-size town.”

Energy efficiency varies widely from company to company. But at the request of The Times, the consulting firm McKinsey & Company analyzed energy use by data centers and found that, on average, they were using only 6 percent to 12 percent of the electricity powering their servers to perform computations. The rest was essentially used to keep servers idling and ready in case of a surge in activity that could slow or crash their operations.

Energy efficiency …

The most commonly used metric to determine the energy efficiency of a data center is power usage effectiveness, or PUE. This simple ratio is the total power entering the data center divided by the power used by the IT equipment.

PUE = Total Facility Power / IT Equipment Power

Power used by support equipment, often referred to as overhead load, mainly consists of cooling systems, power delivery, and other facility infrastructure like lighting. The average data center in the US has a PUE of 2.0, meaning that the facility uses one watt of overhead power for every watt delivered to IT equipment. State-of-the-art data center energy efficiency is estimated to be roughly 1.2. Some large data center operators like Microsoft and Yahoo! have published projections of PUE for facilities in development; Google publishes quarterly actual efficiency performance from data centers in operation.

The U.S. Environmental Protection Agency has an Energy Star rating for standalone or large data centers. To qualify for the ecolabel, a data center must be within the top quartile of energy efficiency of all reported facilities.

European Union also has a similar initiative: EU Code of Conduct for Data Centres.

Apple …

Downloading apps and media files, syncing via iCloud, using SIRI, backing up iOS devices needs an incredible amount of energy. Some of the features are quite wasteful if we think about a new contact entered in Contacts, then sent thousands of miles via the internet to see it some seconds later on a second iOS device which is just two feet apart.

Apple runs its biggest data center in Maiden, North Carolina. It houses servers and telecommunications equipment responsible for iCloud, Siri, iTunes and other online services.

But using Apple’s services in the cloud no longer means polluting the air.

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Apple’s green initiatives, including the company’s huge solar panel installation at one of its data centers in Maiden, show us, that there are ways to support a growing number of connected devices while at the same time shrinking the company’s carbon footprint.

Lisa P. Jackson is Apple’s Vice President of Environmental Initiatives and explains it with using clean energy like solar power, biogas generators, and geothermal energy.

“We feel the responsibility to consider everything we do in order to reduce our impact on the environment. This means using greener materials and constantly inventing new ways to conserve precious resources. [...]
We think this is an opportunity for us and for our sector to leave it (the world) better than we find it, to actually help people convert to cleaner energy without even knowing they’re doing it,”

Jackson said, echoing statements made earlier by Apple CEO Tim Cook.

Greenpeace, which has previously been critical of Apple for sourcing energy from fossil fuels, recently praised the company for improving the energy mix powering its data centers, ranking it above other technology giants such as Amazon.

  • The new HQ (“Spaceship”) being built in Cupertino, will use 30% less energy than an equivalent building, and will be home to around 7,000 trees.
  • Apple decreased the material required to make its products – the new iPad Air uses nearly one-third less material, by weight, than the original iPad.
  • All the company’s retail stores will now take back Apple products for recycling, for free; previously customers had to buy a new product to recycle an old one. In the UK and US, an ongoing scheme offering payments for old iPhones, iPads and Macs also continues.

Are these statements for publicity only?

Well, Tim Cook recently told climate change sceptics that they should ditch Apple shares if they did not like the company’s backing for renewable energy and sustainability.

We do things because they are right and just and that is who we are. That’s who we are as a company. When I think about human rights, I don’t think about an ROI. When I think about making our products accessible for the people that can’t see or to help a kid with autism, I don’t think about a bloody ROI, and by the same token, I don’t think about helping our environment from an ROI point of view.

If you only want me to make things, make decisions that have a clear ROI, then you should get out of the stock.
(Tim Cook, annual shareholder meeting in Cupertino, 2014)

Cook’s call for climate change deniers to “get out of the stock” is an impressive statement I never heard from any other CEO.

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I already reported about Apple’s supplier responsibility (see ‘Related links’) and now it’s worth looking on the environmental initiatives of the company.

Apple’s data centers …

Here are some facts about Apple’s data centers published by the company in context with its environmental initiative in April 2014.

  • Maiden, North Carolina
    We designed our Maiden, North Carolina, data center from the ground up for energy efficiency, and it has earned the LEED Platinum certification from the U.S. Green Building Council – the first data center of its size to be honored.
    On any given day, between 60 and 100 percent of the renewable energy it uses is generated onsite through biogas fuel cells and two 20-megawatt solar arrays- the nation’s largest privately owned renewable energy installation – and we purchase any remaining power we need from entirely clean sources. The Maiden center generates 167 million kilowatt-hours of renewable energy onsite per year – enough to power the equivalent of 13,837 homes.
  • Prineville, Oregon
    Our data center in Prineville, Oregon, is every bit as environmentally responsible as the one in Maiden. We’re building a micro-hydro system that will harness the power of water that flows through local irrigation canals.
    When completed in 2014, it will serve most of the center’s energy needs, In the meantime, since Oregon allows the direct wholesale purchase of renewable energy, we’re able to directly access enough local wind energy to power the entire data center.
  • Reno, Nevada
    Our newest data center, in Reno, Nevada, follows in the footsteps of our 100 percent renewable energy centers in Maiden and Prineville. We’re working with the local utility to codevelop an 18- to 20-megawatt solar array using a new kind of photovoltaic panel with curved mirrors to concentrate sunlight.
    Expected to be operational in early 2015, the solar array will have an annual production capacity of over 43 million kilowatt-hours of clean, renewable energy. Until then, the center will be powered by renewable geothermal energy purchased from the local utility.
  • Newark, California
    Like our facilities in Maiden, Prineville, and Reno, our data center in Newark, California, is powered by 100 percent renewable energy. We hit this milestone in January 2013, when we began serving the data center with energy sourced primarily from California wind power. We’re acquiring this energy directly from the wholesale market through California’s Direct Access program.

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I talked about Microsoft’s construction application for installing diesel engine generators as backup-up sources for energy supply.

Apple goes an alternative way. With several energy-efficiency tricks, biogas-powered fuel cells and a giant 20-megawatt solar array Maiden will be one of the most environmentally benign data centers ever built.

Beyond Apple’s eco-bragging rights, this data center should provide valuable insights to the rest of the cloud computing industry.

Stationary fuel cells are certainly well proven, but multi-megawatt installations are pretty rare. Data center customers for Bloom Energy, which is supplying Apple in North Carolina, typically have far less than a megawatt installed. Each Bloom Energy Server, which takes up about a full parking space, produces 200 kilowatts. By going to 10 megawatts of capacity, Apple can claim the largest fuel cell powered data center, passing eBay which earlier this year announced plans for six megawatts worth of fuel cells at a data center in Utah.

Using fuel cells at this scale potentially changes how data center operators use grid power and traditional back up diesel generators. With Apple’s combination of its solar power and fuel cells, it appears the facility will be able to produce more than the 20 megawatts it needs at full steam. That means Apple could sell power back to the utility or even operate independently and use the grid as back-up power – a completely new configuration.

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Finally I would say that there are not only innovative ideas implemented in Apple’s product line-up but also in it’s ecosystem. A fact which is left behind when talking about Apple’s power as one of the most innovative companies in the world.

Better …

An official spot about “leaving the world better than we found it”.

(1:49 min, published April 21, 2014)

Summary …

“We can’t solve problems by using the same kind of thinking we used when we created them.” (Albert Einstein)

It all started with implementing unlimited capabilities into electronic devices and it ends in unlimited pollution of our environment. “Think different” now means to replace limited classical energy sources by natural unlimited sources. The reason why it doesn’t take place today is just money. Selling cheap electronic devices goes along with ignoring the fact that there is a climate change, and pollution of air and water.

Related links …

Apple: Product Environmental Reports

Power, Pollution, and the Internet

Emerson Network Power Infographic

Apple’s Supplier Responsibility

Thanks for going green or blue or whatever you call it.





Understanding the WEB

29 09 2013

For many people it’s a daily task to use the internet for business or private purposes, for improving knowledge, access bank accounts, sharing information on the big social networks, or just surfing for fun.
Since the mid-1990s the internet has a tremendous impact on culture, commerce, science, and the way how people communicate (E-Mail, Social Networks).

Less people know how the WWW really works.

Here is a short description as well as a review of the app EAW (Explain the Web) with which teachers can create some background information for their pupils.

The Internet …

Wikipedia
The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite (TCP/IP) to serve several billion users worldwide. It is a network of networks that consists of millions of private, public, academic, business, and government networks, of local to global scope, that are linked by a broad array of electronic, wireless and optical networking technologies. The Internet carries an extensive range of information resources and services, such as the inter-linked hypertext documents of the World Wide Web (WWW), the infrastructure to support E-Mail, and peer-to-peer networks.

TCP/IP network access expanded again in 1986 when the National Science Foundation Network (NSFNET) provided access to supercomputer sites in the United States from research and education organizations, first at 56 kbit/s and later at 1.5 Mbit/s and 45 Mbit/s. Commercial Internet service providers (ISPs) began to emerge in the late 1980s and early 1990s. The Internet was commercialized in 1995 when NSFNET was decommissioned, removing the last restrictions on the use of the Internet to carry commercial traffic. The Internet started a rapid expansion to Europe and Australia in the mid to late 1980s and to Asia in the late 1980s and early 1990s.

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The connection …

Here is an infographic about the steps to connect to a website.

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The app EAW …

Explain a Website (EAW) is a specialized screencasting tool that allows recording the interaction with a website within the iOS web browser.

How does it work?

You enter the name of a website in the address bar and tap “Go” on the keyboard. The browser will display the chosen website. You can then draw on various elements of the website or highlight them, while talking. Everything will be recorded as an EAW project. You can then export the project to various cloud services or publish on YouTube.

The toolbar at the bottom of the screen contains three sets of buttons – on the left, drawing and highlighting tools, in the center – recording and playback, on the right – save/load functions.

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Possible applications …

  • Teaching children about the usage of websites.
    See also
    the app Explain Everything by Morris Cooke
  • Discussing a website design with colleagues.

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Disadvantages …

  • Only hand-written annotations are possible.
    So a touchscreen pen is an indispensable tool.
  • Annotations cannot be created as separate files referring to a specific position on the website.
  • Some more saturated colors for marking would be useful.
  • The app cannot be used in portrait mode which is often useful when explaining websites.

Related links …

Internet stats

Glad to have you here on http://iNotes4You.com.
Thanks.





PDF the Web

4 09 2013

With one command entered in the address bar of SAFARI you can seamlessly convert a website into a PDF document. No third-party app is needed. Added to the Bookmarks Bar of your browser the creation of a PDF is permanently available. With the commands ‘Print’ and ‘Open In’ the websites content can be easily transferred to other apps like Documents by Readdle, Apple’s iWork Suite, or sent by E-Mail.

Remark …

This post is based on a publication of

Mariam Yusuf on Technoduet

Thanks Mariam.

There are many scriptlets available which can be used e.g. to open an application on an iOS device. Mariam’s example can also be used with all browsers available for iOS devices.

And by the way I suggest visiting Technoduet, a great website to get information about all things tech.

The How-To guide …

Step 1 Open any website in Safari

Step 2 Tap on the Action button to Bookmark

Step 3 Select Bookmarks Bar

Step 4 Enter bookmark parameters

Title

SaveAsPDF

Address

javascript:pdf_url=location.href;location.href=’http://pdfmyurl.com?url=’+escape(pdf_url)

(Use the clipboard to transfer the command.)

Location

Bookmarks Bar

Step 5 Tap on Save.

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The new bookmark is located at the end of your Bookmarks Bar list.
Tap on Edit in the Bookmarks Bar list and move SaveAsPDF to the first position. This ensures that it’s always in your field of vision.

Prerequisites …

As you can see the command uses Javascript and should be shown in the bookmarks bar. This requires the following settings:

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Note
Javascript
JavaScript lets web programmers control elements of the page—for example, a page that uses JavaScript might display the current date and time, cause a linked page to appear in a new pop-up page or provides a Print button.

Using SaveAsPDF …

If you now want to convert a website into PDF file format just tap on SaveToPDF in the Bookmarks Bar. The PDF is generated by a function implemented in the iOS operating system.

If you tap on the PDF the commands ‘Print’ and ‘Open In’ will be available for further processing.

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There is a high-rated app available which allows non-linear presentations of slides. It’s Final Argument by Morris Cooke, UK.

See an app review here
Final Argument

The presentation slides can be arranged in a mind map-like outline. Single pages or the whole website can be assigned to a slide.

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This image shows an application of saving a website as PDF. The Apple website about iOS 7 was captured with ‘SaveAsPDF’ and a single page then was assigned to a slide of a presentation about the new operating system.

Applications …

  • Retrieving text from the PDF
  • Read later in a PDF Reader without animations
  • Annotations to an article with an annotating capable app
  • Adding parts of a website without loosing the formatting as a PDF file attachment

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Some pros and cons …

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Not recommended …

On a serious note do not …

  • Save Google searches as PDF
    Later on you have to enter all the useful addresses manually.
  • Record all websites you visited
    Your device’s memory won’t let that happen.

Thanks for visiting http://iNotes4You.com.





Apple Wireless Network

11 08 2013

Apple AirPort Extreme is Apple’s router for Internet access. It’s directly connected to a modem and provides wired as well as wireless access for computers, mobile devices like an iPhone or an iPad, printers, and media devices.
Apple offers three different routers (Airport Express, AirPort Extreme, Time Capsule) which can be connected to either a DSL or a Cable modem.

A complete wireless network build with solely Apple products follows the the company’s strategy to provide users with a perfect experience regarding design, setup, and reducing features to those which are necessary. KISS is the motto.

KISS
KISS = Keep it simple, stupid
A design principle noted by the U.S. Navy in 1960 that states that most systems work best if they are kept simple. Unnecessary complexity should be avoided.
Variations of this phrase are:
Keep it simple sir, Keep it simple and straightforward, Keep it short and simple, Keep it simple or be stupid

The hardware …

See this mind map which summarizes all properties of Apple’s hardware for wireless networking with mobile devices. As you can see Apple built it’s own ecosystem where components perfectly work together.

Remark
The router hardware was replaced by new versions on June 10, 2013 on occasion of Apple’s WWDC.

Here are the main features of Apple’s routers summarized in a mind map.

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Feel free to download this map from my Box account.

The alternative file formats have been created with iThoughts HD for iPad (.ITMZ file format). Compatibility to other tools is limited.

Application File format
Adobe Reader PDF
iThoughts ITMZ
MindManager MMAP
XMind XMIND

Please visit

The Apple group on Biggerplate

to see and download all mind maps related to Apple.

This more realistic view shows the kernel with a modem and the router as well as some examples of wirelessly connected hardware components for interactive usage.

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The integration of all you need for a perfect user experience goes along with limitations when using non-Apple hardware. It’s Apple’s strategy to say NO to some features other vendors offer and to say YES to a seamless integration of its hardware with its custom-built software.

Professionals may argue that performance, configuration options, and price is not what should be expected. On the other hand the running system convinces users who see the technology as as a serving and not an experimental environment. So do I after many years with other configurations not following the motto ‘It just works’ or ‘Buy, connect, and use it’ for the tasks you want to use it for.

A complete configuration …

Follow these steps in the order specified.

Step 1 Connect the modem to the multimedia connector with a coaxial cable.

Modem
A modem (modulator-demodulator) is a device used to connect a computer or router to a telephone/cable line to allow the computer to connect to the Internet. It modulates a carrier signal to encode digital information, and also demodulates such a signal to decode the transmitted information. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data.

Step 2 Connect the modem to the power supply.

Wait until the LEDs indicate a functioning connection to your ISP. It may take up to 30 min.

Step 3 Connect the APE to the modem with an Ethernet cable.

Ethernet cable
Ethernet cabling is standardized. If you go to a store you may find a variety of “categories” of cabling. These categories tell you the quality of the cabling. The quality determines, essentially, how much the cable can handle. Recommendation: Cat 6 – works for 10/100/1000Mb.

Step 4 Connect the APE to the power supply.

Here we go.
The configuration with any iOS device and the helper apps Settings and AirPort Utility starts.

Open Settings on your iPhone or iPad and tap on WiFi.
The APE already is sending signals so that your device suggests the set up of a WiFi network.

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Tap on the right-pointing arrow to set up an AirPort basestation.
Enter a name for your network and set a password. Other users like your neighbors, if not too far away, will see this name as an additional WiFi network. Use a strong password for joining this network.

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Tap on Next and that’s all.
Your new WiFi network will connect all your devices with the internet after entering the password you set for your network.

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The utility app …

For controlling the network Apple offers an app called ‘Airport Utility’ which is available for iOS devices, Macs, and Windows PCs.
The slideshow shows the usage of this app when configuring a wireless network with an Airport Extreme router connected to a cable modem.

The most important configuration options can be controlled with the app for iOS devices. For some less important options like adjusting the signal strength Airport Utility for computers must be used.

The benefits …

Apple’s ZEROCONF technique minimizes your efforts to install a usable internet access.

Zero configuration networking (zeroconf)
is a set of techniques that automatically creates a usable Internet Protocol (IP) network without manual operator intervention or special configuration servers.
Zero configuration networking allows devices such as computers and printers to connect to a network automatically. Without zeroconf, a network administrator must set up services, such as Dynamic Host Configuration Protocol (DHCP) and Domain Name System (DNS), or configure each computer’s network settings manually, which may be difficult and time-consuming.

Apple does not permit the AirPort Extreme to engage in channel bonding on the 2.4GHz frequency band. This is a very neighbor-friendly policy, because only three channels in this band—channels 1, 6, and 11—don’t overlap. A router engaging in 2.4GHz channel bonding can hog more than its share of bandwidth and will likely interfere with other 2.4GHz routers operating nearby.

The AirPort Utility also makes it very easy to update the router’s firmware. The AirPort Extreme is so much easier to set up than any other router of the many competitors.
The reason is that if you stay in Apple’s ecosystem you will benefit from all the efforts Apple did for an easy-to-use experience.

The performance on 802.11n standard transmission technique is high.
The APE is powerful even if thick walls hamper propagation of electromagnetic waves.

Interference …

In physics, interference is a phenomenon in which two waves superimpose to form a resultant wave of greater or lower amplitude. Interference usually refers to the interaction of waves that are correlated or coherent with each other, either because they come from the same source or because they have the same or nearly the same frequency like electromagnetic waves sent from WiFi networks.

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If you get problems with interference or the performance of your network is slow which may be caused by interference follow these guidelines:

Apple about potential sources of interference

Macworld, Troubleshooting Airport Interference

The Airport Utility …

Apple’s ZEROCONF technique minimizes your efforts to install a usable internet access.

Zero configuration networking (zeroconf)
is a set of techniques that automatically creates a usable Internet Protocol (IP) network without manual operator intervention or special configuration servers.
Zero configuration networking allows devices such as computers and printers to connect to a network automatically. Without zeroconf, a network administrator must set up services, such as Dynamic Host Configuration Protocol (DHCP) and Domain Name System (DNS), or configure each computer’s network settings manually, which may be difficult and time-consuming.

Look at the details to get a deeper understanding of what happened when configuring the network.
To see the details of your own WiFi network go to Settings – WiFi and tap on the right-pointing blue arrow of you network. Go to the bottom and tap on ‘Manage network’. This will open the Airport Utility. Airport Utility can be used to individualize the configuration.

Regarding to my blog Network (1) from April 20 you will now understand the configuration details set by the APE:

  • DHCP ON
    the APE acts as a DHCP server and assigns private IP addresses (10.0.1.x) to all devices joining the WiFi network after entering the password.
  • NAT ON
    the APE does the network address translation that means, NAT converts your private LAN IPs into a external WAN IP
  • Security
    the APE encrypts all WiFi network traffic with WPA2
    (Wi-Fi Protected Access II (WPA2) is a security communication protocol developed by the Wi-Fi Alliance to secure wireless computer networks)

This slideshow shows all settings displayed in Apple’s app AirPort Utility:

This slideshow requires JavaScript.

In addition to the automatic configuration I entered the following settings:

  • Reservations for IP addresses
    the APE reserves an IP address for all devices. Reservations are useful if you want that the DHCP feature of your APE assigns a fixed IP to your devices. Otherwise DHCP is free to assign any free IP address in the range 10.0.1.2 – 10.0.1.200 every time you join your network.
  • 5 GHz network
    The APE works in the 2.4 and 5 GHz frequency band. The iPad is able to connect on the 5 GHz band and I named this (second) network as ‘Apple Airport 5 GHz’.
    If you have interference problems with other WiFi networks you may vary the channel or move over to the 5 GHz network.
  • With the help of Airport Utility for PCs I additionally limited the signal power to 50% which is enough to get connected in all rooms and hampers other WiFi capable devices outside my home to detect my network.

The result is a working internet connection checked by the app Fing which is available at Apple’s App Store.

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The disadvantages …

The AirPort Extreme has only one USB 2.0 port, so it can share either a printer or a storage device over your network. This is in the line with Apple’s strategy that printers should be connected via AirPrint. I miss the support of USB 3.0.

Apple’s design decisions help its product blend into a home’s décor and so the old version of AirPort Extreme was designed to rest flat while the new version was redesigned in June 2013 due to an improved output power. It’s still an eyecatcher.

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Related links …

Airport Extreme Tec Specs

Airport Extreme User Guide

Airport Extreme Easy Setup

Setting up your wireless network

Cisco, 20 Myths of Wi-Fi Interference

Thanks for visiting my blog.
Wireless as well as wired connections are welcome.





Network (3) Port Forwarding

25 04 2013

Parts (1) and (2) of my articles about networks gave you some basic knowledge about networks and discussed the possibility to connect from the LAN to the WAN or in other words from the devices at home to the webservers in the outer world.

The reverse way, connecting from WAN to LAN, is basically not possible. Only in case of requests from a device within the LAN data goes the reverse way, e.g. entering an URL like http://iNotes4You.com as the request and getting the answer (the website content) delivered by WordPress.com servers.

The main reasons why a WAN-LAN connection won’t work:

  • 1 Most of the ISPs (Internet Service Providers) assign varying IP addresses to your connection so that it is not possible to keep a stable connection over the time.
  • 2 For security reasons nobody should be able to compromise your LAN.
    So a Firewall/Router will not accept incoming requests which were not initiated by a device within the LAN.

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The solution is Port Forwarding an applications communication with another application.

Dynamic DNS …

The first problem of varying WAN IPs can be solved by using a service called Dynamic DNS (DDNS). Some companies offer this service without charging.

For example you can register at no-ip.com. After completing the registration process you can define a hostname and download the so-called DUC software (Dynamic Update Client) which has to be installed on the computer you want to connect to.

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The main idea is to get a HOSTNAME which can be used instead of the varying WAN IP. The DUC client on the computer inside the LAN frequently determines the actual WAN IP and transmits the result to the DDNS provider. Your request from outside your LAN first is transmitted to your DDNS provider via the HOSTNAME. DDNS returns the actual WAN IP of your LAN and a connection can be established.

So DYNAMIC DNS SERVICE provides a constant ALIAS for a varying WAN IP of your LAN.

Opening the firewall …

You already know that data on the Internet is sent to and from IP addresses. Sending or receiving data is done on ports. Ports are virtual pathways on which Internet data flows.

For a Watchguard SOHO Firewall a custom service has to be defined and the related traffic has to be allowed. The service must include the definition of an IP of the computer you want to connect to as well as the port for communication.

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While things may differ slightly depending on your Firewall’s/Router’s firmware, the below mentioned fields are pretty standard:

  • Application or Service Name
    The name of the application you’re forwarding this port for. You can use any descriptive text you want—this field is here to help you remember why you set this up; like the name suggests, you normally want to use the name of the application you’re setting up port forwarding for. I’s a good idea to also include the computer’s name along with the service if port forwarding is used for the same applications on different computers.
  • Port to
    ‘Port to’ is the port on your local IP address. If you were setting up VNC for a local computer, you’d fill this in with 5900 as that’s the standard port number for VNC services.
  • Port from
    ‘Port from’ is the port on your external IP address. Generally you use the same port as entered in ‘Port to. This works just fine when you’re configuring only one machine for one type of service. But say you wanted to be able to remotely access two or more computers using VNC. If you used 5900 on a single, external IP address they would be in conflict. The router would see a request for port 5900 and not know which Local IP address should handle that request since the port forwarding table has two. To solve this problem, you can use the standard port for one and not for the other—kind of like an apartment building has a single address but multiple apartments. You can use port 5900 for one and 5901 for the other computer. In that case you have to first set the port (the computer you want to access) when using VNC on an external IP address. This way you can set up identical services with a single External IP and different Local IPs without conflicts.
  • Protocol
    This is where you specify whether or not your service uses the TCP protocol, UDP protocol, or both. When you look up your ports you’ll also want to make note of the protocols used. In most cases it will just be TCP.
  • IP Address or Service Host
    This is where you specify the LAN IP of the computer you want to access. You can easily find this information in your computer’s network settings. The IP address will generally be in the 10.0.x.x, 192.168.x.x, or 172.31.x.x format. Because these IP address are generally dynamic (changing over the time), you have to set up static IPs or so-called DHCP reservations.
  • Enable
    You need to enable the port forwarding rule (on Watchguard routers you do it by setting the rule to ALLOW). By using DENY you are able to save the rule but it won’t be active or function in any way.

The firewall is now opened for authorized incoming traffic to a specific computer using a specific port.

The communication is done by the VNC Server software which can be downloaded from the RealVNC website.

After installing the DUC client software from No-Ip and the VNC server software from RealVNC on your PC it looks like this:

20130223-123521.jpg

VNC viewer on an iOS device …

To configure the VNC Viewer app on an iOS device you just have to enter the HOSTNAME, the PORT for communication and the credentials you defined in the VNC Server software on your computer.

20130223-122829.jpg

Summary …

The connection to a computer inside a LAN from an iOS device outside the LAN works with a

  • Dynamic DNS account and an Update Client (DUC)
  • Configuration of the firewall for a specific computer and a specific communication port
  • Server software (VNC Server) on the computer
  • Client software (VNC Viewer) on the iOS device

In a typical small office environment, a router assigns private network addresses to internal computers while the router gets a public IP from the ISP.
If the public IP is not static, Dynamic DNS services must be used to configure the VNC Client
by using the Dynamic DNS address instead of an IP address.

Connection to a computer in the LAN requires an installation of VNC Server software.
A unique port number must be assigned to each computer that should be reached from outside the LAN.
20130223-134054.jpg

Useful links …

Former articles about networks

Network (2) Apple Airport Router

Network (1) Addressing

If you want to use Port Forwarding you should visit

Portforward.com

Port Forwarding VNC on Apple Airport

You will find the settings for many Soft- and Hardware products as well as a software product called PFConfig which supports automatic configuration (29.29$).








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