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Archive for the ‘General Commentary’ Category

Different perspectives exist for the same thing. While no two people look at the world in exactly the same way, two people when they collaborate look at the world in a completely new perspective that borrows from individual perspectives. I got the idea of using colours in Venn Diagrams to represent this. In this post, I present some applications of this idea.

Figure 1: Success of a Team Project
Success of a Team Project

 

 

 

Figure 2: Job Satisfaction and Effectiveness
Job Satisfaction and Effectiveness

 

Figure 3: The Market Place
The Market Place

 

Figure 4: Today’s Mobile World
Today’s Mobile World

 

Figure 5: Evolution of the Market Place
Evolution of the Market Place

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Following from the title of this blog site, I seek to clarify the differences between “mobile” and “wireless”. These two terms are often used interchangeably, in a rather loose way. Much of this is justified because they are closely related. In fact, many products share the characteristics of both so that any distinction that we may try to bring about becomes rather difficult without referring to specifics.

Yet another reason for the confusion is that “mobile” has multiple connotations. In the good old days before mobile telephony and cell phones, “mobile” meant not fixed, ie. portable. These days we often mean a mobile phone when we say “mobile”.

Here lies the clue to our clarification. In strict terms, “mobile” means portability. “Wireless” means connectivity. That’s just a definition. What are the characteristics? Some examples will make this apparent.

A UMTS Node-B is a wireless device but it is not mobile. A digital camera of the 1990’s is mobile but it is not wireless. Today’s digital cameras are not only mobile but also wireless because they have Bluetooth, infrared and possibly Wi-Fi connectivity. The iPod has always been a mobile device but only with the most recent release of iPod Nano has it become wireless with Wi-Fi connectivity.

Portability requires that the device has a suitable form factor. It must be durable from the consumer’s perspective with some ability to withstand rough transport or fall. It must have a feel-good factor. The device must be power efficient and must have a long battery life. No one talks about battery life for the Node-B because it’s not a mobile device. In some sense, the nature of service provided by the device makes it mobile and requires it to be mobile.

On the other hand, a connected device enables services to be delivered in collaboration with those around it. For example, a conventional laser printer is of little use if it’s not connected to a computer via a parallel port. Thus, connectivity is often linked to services obtained or offered in a collaborative environment. Connectivity implies an environment in which devices are physically separate entities.

Connectivity can be wired or wireless – we are interested in the latter. A modern printer connected to a PC via Bluetooth is a fixed device but it is wireless. For the printer, the PC acts as a data source. For the PC, the printer provides a printing service. A mobile phone is both mobile (in the strict sense) as well as wireless. A mobile device may be self-complete. A wireless device is likely to be incomplete by itself. It needs to get connected.

These days, the term “wireless” when used specifically for mobile phones, laptops or PDAs generally refers to connectivity to the Internet. In other words, the specific service that the term eludes to is the conglomerate of all services that the Internet can offer. While the “wireless” component of a mobile phone enables it to connect to the base station, the term has come to mean the end service as perceived by the user. The man on the street does not want to connect to the Node-B. He wants to access his e-mails from his office mail server.

A cellular phone is obviously both mobile and wireless. It is portable and at the same time it has to stay connected to the base station. Special considerations are in play here in addition to what has already been mentioned. The device must be capable of many or all of these:

  • Resilience and recovery in a fast-fading environment
  • Ability to make continuous measurements of the radio environment
  • Support seamless handover to stay connected
  • Dynamic power control
  • Adaptive Modulation and Coding (AMC)
  • Incremental Redundancy (IR)
  • Support Automatic Repeat Request (ARQ) across the wireless access

It will be apparent that a device that is both mobile and wireless, is a fairly complex one. However, this is true only for a subset such as a cellular phone. Other devices are much simpler. For example, a digital camera is a mobile device. It may have Bluetooth connectivity to transfer images to the laptop. However, while such an image transfer is in progress it is likely to be non-mobile w.r.t to the laptop or at worst, mobile at pedestrian speeds (such as the user moving the laptop around during the image transfer). A logical representation of device categories is given in Figure 1.

Figure 1

Mobile & Wireless Venn Diagram

So far I have looked at the issue from a telecom perspective. Let us look at it from the world of IP (Internet Protocol). This is important as telecom and IP are building bridges with the building blocks of IMS, SIP and all the services that they enable. “Mobile” for IP means that designers have to tackle issues such as addressing, address translations and packet routing. “Wireless” for IP is nothing more than an access mechanism. On the other hand, “wireless” means a lot more for TCP/IP. The performance of TCP/IP on a wired network is different from a wireless network. In a future article, I will cover the performance of TCP/IP over wireless.

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Before starting to write something of my own, I thought it would be a good idea to survey what’s already on the Web. I was not surprised to find that there is much more than what I could read and digest. There are blogs that have been around for many years, some no longer maintained but many still active with regular postings. There are blogs recently started and we can note that with each posting the quality of the content improves. There are blogs started and maintained by individuals. On the other hand, there are blogs to which multiple authors contribute.

There are blogs hosted on Google. Typepad is another popular site for technical blogging. There are those that offer free hosting and others that have a wide range of pricing. Yesterday I tried hosting this on Yahoo! 360. Yahoo! 360 isn’t the best blog site but it’s handy for me because I have a Yahoo e-mail id. Recently Yahoo’s e-mail frontend has improved vastly so much so that I manage my calendar, contacts, e-mails, messaging and RSS feeds from a single interface. Unfortunately, Yahoo! 360 was clumsy. It is not ideal for blogging on technical stuff. It is more for social networking and sharing photos. A simple thing as embedding pictures within blog entries was not possible. So I switched to WordPress and its cool!

Here’s a quick list of blogs in the wireless and mobile space:

 
  1. http://3g4g.blogspot.com/
  2. http://blog.seattlepi.nwsource.com/venture/
  3. http://blogs.cisco.com/wireless/
  4. http://business-mobile.blogspot.com/
  5. http://darlamack.blogs.com/darlamack/
  6. http://freedomail.typepad.com/blogfreedomailcom/
  7. http://mobilesociety.typepad.com/mobile_life/
  8. http://news.techdirt.com/news/wireless/
  9. http://opengardensblog.futuretext.com/
  10. http://uwbblog.typepad.com/the_ultra_wideband_blog/
  11. http://windia.blogspot.com/
  12. http://www.abiresearch.com/Blog/Wireless_Blog
  13. http://www.arstechnica.com/
  14. http://www.biskero.org/
  15. http://www.chetansharma.com/blog/
  16. http://www.computerworld.com/blogs/mobile
  17. http://www.dailywireless.org/
  18. http://www.engadgetmobile.com/
  19. http://www.funambol.com/blog/capo/
  20. http://www.gigaom.com/
  21. http://www.gizmodo.com/
  22. http://www.intomobile.com/
  23. http://www.m-trends.org/
  24. http://www.mobhappy.com/
  25. http://www.mobile-weblog.com/
  26. http://www.moconews.net/
  27. http://www.mopocket.com/
  28. http://www.oreillynet.com/etel/blog/
  29. http://www.phonescoop.com/
  30. http://www.textually.org/
  31. http://www.thewirelessreport.com/
  32. http://www.wirelessduniya.com/

My favourite is my friend’s blog from the UK [1]. Almost all of what he writes is of interest to me. You can expect to find similar but not the same posts in my blog. Martin’s blog [7] is what I like next. He goes into the specifics of mobile technology and that’s exactly what interests me. His blogroll contains further links that may interest you. Cisco’s blog [3] has good stuff but the focus is on fixed wireless rather than mobile wireless or cellular technologies. Business travellers may want to visit [4]. Ajit Jaokar’s blog [9] has been around for more than two years. He has good reputation in the industry and his blogs have much useful information. There are blogs that relate particularly to the Indian market [11, 15, 32]. There are blogs focused on gadgets along with other relevant stuff [18, 29].

With so much around, I don’t intend to make copies of news articles which is what happens quite often at many blog sites. In fact, in my blogs I intend to introduce, compare and analyze wireless technologies. I hope the content will appeal to experts and newbies alike. Technology by itself is of little use without application. Application by itself will never happen without a market. Markets themselves will never evolve without sustainable business cases. I intend to make links amongst all these factors.

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