Author: Martin

How To Survive With Free WiFi in the US

Here I am in Boston and thanks to no data roaming agreements and use of different frequencies for UMTS my 3G mobile phones are pretty much useless. Well, pretty much but not quite as my N93 has Wifi on board which works over here just as well as back in the old world. So before I started my recent trip to Boston I was not quite sure how well free and municipal Wifi would keep me connected. After having been here for a couple of days, here’s what I experienced:

Free Hotel Wifi

Before coming over I searched the net if there are any hotels which have wireless Internet access included in the room price. While you would not find such a thing in Europe, there are actually a number of chains in the US that do this. A quick search came up with BestWestern and DaysInn hotels. It’s important to check that Wifi is  available in all rooms or at least in the room you reserve. Otherwise, "Wifi available" could also mean that you can only surf in the lobby. I decided to stay in a DaysInn hotel as the room rates are around 75 dollars a night including Wifi. I double checked availability by calling the hotel before making the reservation and was not disappointed. The Wifi signal in the room was strong and the bandwidth with about 400 – 600 kbit/s good enough for VoIP, web surfing, business and of course, blogging.

Wifi on the Go

Salemopen
I like to check my eMail and my favourite news web sites every now and then while I am on the move so the next crucial thing was whether there were enough open Wifi hotspots along my path to keep me connected. I toured Salem, Portsmouth and Boston and was never disappointed. Many coffee shops along the route offered free Wifi. Salem was the most noteworthy city with free Wifi almost at every corner. This might be due to the SalemOpen.Net initiative started back in 2004. Well, it paid out to get me as a customer as the local coffee shops sold more to me than if there had been no Wifi around. I also noticed that many restaurants and coffee shops offer free Wifi without advertising it at the door. Some of them seem to do it intentionally as their Wifi network name (SSID) is usually the name of their business. Others just seem to have put a Wifi access point in place without doing anything and I encountered "linksys" access points more than once. Well, thanks for the ride.

While small businesses seem to have caught the idea of offering Wifi to their customers as an incentive to come and stay, bigger businesses like for example "Borders Books" only offered paid Wifi. Well, looks like they don’t need the moving elite to buy books from them. Also, I found directories of establishments offering free Wifi like this one a good thing to get a first idea of what’s available where you go but it’s impractical to plan your trip around the locations that are listed.

Summary

All in all I am quite happy to see that the idea of open and free Wifi for customers has taken hold in the U.S. (or at least here in Massachusetts) and much more so than in Europe where this phenomena is not yet wide spread. Also searching for free Internet access before sitting down somewhere is a charm with a Wifi enabled phone or PDA. If I lived here, however, I’d still take a service contract from one of the wireless operators, as hunting for a hot spot is definitely not something I would like to make a habit out of.

HSDPA And Simultaneous Circuit Switched Voice Calls

In theory, 3GPP standards allows simultaneous HSDPA and circuit switched voice calls on a DCH. The standard even describes how the terminal can signal the maximum speed to the network it supports on a DCH while an HSDPA session is ongoing. In practice, however, this does not seem to be implemented yet.

While testing such a scenario with a Motorola V3xx in practice I noticed that an incoming circuit switched voice call makes the radio network interrupt the HSDPA session, put the data connection on a dedicated channel (DCH) and then opens an additional dedicated channel for the voice call. During the voice call data transmission is possible with 64 kbit/s in one network  (Tim, Italy) and 128 kbit/s in another (SFR, Paris). In a third network I tested this scenario the incoming call was not delivered at all. As this network has not officially launched HSDPA yet, I grant them anonymity.

After the voice call is over I would have expected that the networks put the data connection back onto HSDPA. I was quite surprised that this was not the case. Instead, the DCH was upgraded to 384 kbit/s. It would only go back into HSDPA mode once the data transfer is interrupted. While this is not a problem for web surfing, where many interruptions occur, this behavior is very undesired for file downloads. Here, the file download will continue but never be put back on a faster HSDPA connection.

Vodafone_italy_file_downloads_int_2
The picture on the left shows the result of the test run. At first the download speed is around 75 kbyte/s. Then a voice call is started. This shows on the graph with the short interruption of the data traffic followed by a download speed of around 7 kbyte/s (64 kbit/s bearer). After the voice call is over the DCH speed increased to around 40 kbyte/s (384 kbits/s). The second part of the graph shows a repetition of the test (to make sure I was not dreaming).

Looks like it is still early days for HSDPA. While switching from HSDPA to DCH during a voice call could be both a network or a mobile implementation limitation, not switching back to HSDPA after the call very much seems like a network limitation to me.

How To Get An Unlocked USB HSDPA Adapter

These days most 3G operators offer 3G or HSDPA data cards or USB modems that come bundled with a 24 month subscription. In some countries they also sell them without a subscription but in most cases the data cards are still locked to SIM cards of the operator. As I travel a lot this a somewhat unfortunate situation as some countries have started to offer data on prepaid SIMs. I needed to find a different solution.

So here’s a simple solution: Instead of buying a dedicated PCMCIA or USB HSDPA adapter it’s also possible to use a number of recent phones as HSDPA adapters for a notebook. Prices for most of them are even lower than prices for the data cards. I’ve taken a look at the following 3.5G phone models currently available in Italy:

  • Samsung Z560
  • Samsung Z620
  • Samsung Z630
  • Motorola RAZR V3xx

I decided to go for the V3xx as the price of €245.- was acceptable and in the range, if not even lower, than dedicated HSDPA adapters. It’s slightly TIM (Italy) branded but unlocked. Also, it charges over the USB data cable so no need to carry an extra charger while traveling. And the cream on the top: It’s a category 6 device, i.e. capable of HSDPA speeds of up to 3.6 MBit/s.

I’ve tested it so far in three of the four Italian networks in Rome and additionally in SFR’s 3.5G network in Paris. They all worked well except for the TIM network which would just not work with the mobile for data connections. Very very strange as the mobile is TIM branded. And no, I am not stupid the configuration parameters were correct, I double checked with my SierraWireless HSDPA PCMCIA card.

Another advantage of a USB HSDPA device compared to a PCMCIA or ExpressCard device is that it can be put in a spot where network coverage is better than at the location of the notebook. As shown here, good network coverage makes a huge difference with HSDPA.

For more on "HSDPA" click on the right of the date below.

Who’s On Air At 1900 MHz in Boston For A EU Mobile?

I am back in the U.S. after 8 or 9 years of absence, reflecting my first impression over pancakes at Denny’s. Glad to see that since my absence GSM networks have sprung up here as well and my triband phones pick up both Cingular and T-Mobile U.S. just fine.

My German T-Mobile prepaid SIM card works just fine for both incoming and outgoing calls and even GPRS (no comment on costs though…). T-Mobile’s network around Boston has EDGE activated but since the cost for my roaming SIM card is prohibitive I rather not make any speed tests. Strange that Cingular still runs on GPRS, no EDGE in sight here.

My E-Plus (KPN) prepaid SIM card is also able to attach to both the T-Mobile and Cingular networks and incoming calls work fine. No GPRS though and outgoing calls are blocked. I already knew from their Web site but I would have liked to be positively surprised.

Two Additional UMTS Prepaid Internet Access Offers In Germany

I like it when competition works! A couple of months ago, three German Mobile Virtual Network Operators (MVNO’s) of E-Plus (KPN) lowered their prepaid mobile Internet access prices to 24 cents per megabyte. At the time, AldiTalk was the clear winner since it was the only one that did not only allow the use of E-Plus’ GPRS network but also of it’s UMTS network. Today Teltarif announced that Blau and Simyo customers can now also UMTS. Existing customers need to exchange their SIM cards.

Teltarif further reports that T-Mobile Germany MVNO "klarmobile" will also launch a prepaid wireless Internet access offer soon. I am curiously waiting for the details.

DMedia Announces GSM/WiMAX Mobile

WiMAX World in Vienna, Austria has just started so we are probably going to see a couple of interesting WiMAX announcements in the next couple of days. Nokia already announced some time ago that they are working on a WiMAX mobile phone for 2008. No details given so far. Now, DMedia (Taiwan) and Comsys (Israel) have announced that the former is in the process of developing a WiMAX/GSM/GPRS (GPS) handset/PDA for release in 2008.

No further details are given and the web pages of the companies at this point also don’t contain any more details so it’s about as much vaporware as the Nokia announcement at this time. However, this vaporware announcement is a bit different.

First, it seems that they have understood that a WiMAX only mobile will not be worth much. First network deployments, similarly as when 3G first started, will be patchy at best, so users will need an alternative when not in a WiMAX area. One could even go as far as to speculate that GSM will be used for voice traffic even in WiMAX covered areas. That would make mobile WiMAX deployment a lot easier as coverage would not have to be engineered to have margin high enough to allow smooth handovers for voice calls at cell edges. Also, WiMAX operators could slowly ramp up their mobile VoIP offerings instead of getting battered by lousy mobile performance in the beginning.

And second, the announcement also shows that with a bit of luck, WiMAX will give back benchers in the mobile terminal market such as DMedia (ever heard of them before?) a chance on the market.

Original Source: Heise

Interesting Data On Rural 3G Deployments

Here’s a link to another fascinating article published in an Ericsson’s "Review" periodical. This one deals with the technology and business case to cover rural areas with 3G WCDMA HSPA for mobile telephony as well as for fixed and mobile broadband Internet access. I was quite surprised to see Ericsson disclosing and discussing a number of very interesting numbers in a public paper.

One part of the document deals with the technical background information on the WCDMA 850 MHz network deployment by Telstra in Australia. The paper describes how different factors such as antenna types and configuration of base stations, indoor and outdoor directional antennas at customer sites influence both the coverage area of a base station and throughput per user at the cell edge. Ericsson says in the paper that the typical rural 3G cell in the Australian outback has a cell radius of 60 km.  Indirectly, they also mention in that for this scenario the land needs to be flat, the radio tower needs to be very high and directional outdoor antennas are required at the subscriber’s home. Note: Telstra’s got a coverage map online here, type in 6450 as postal code to get started)

Another part of the document deals with a business case for a 3G network generally and for rural deployment specifically. They base their calculation on a network with an average rural cell radius of 12 km and 15 inhabitants per square kilometer. Some noteworthy figures:

  • CAPEX for upgrade of an existing GSM site to 3G: € 240.000. I assume this is the price of the base station plus site preparation, installation, etc.
  • For their calculation they use a voice telephony ARPU (average revenue per user) of €15.- a month, €3.- a month per subscriber for mobile data and €1.- a month per subscriber for mobile TV. In addition 40% of the subscribers use the network for broadband Internet access as ADSL is not available.

With those numbers, Ericsson calculates that the cell generates €212.184 a year in voice, mobile handset data and mobile TV revenues. Broadband internet adds another €132.000 to that. A clear statement that data revenues are strong but the main revenue is still made with mobile handset voice and data applications. With a 6 year deprecation and annual OPEX costs of €40.000 of the cell, Ericsson estimates the cost of the cell to be around €80.000 a year which translates into a gross margin of the site to 75%.

And finally it’s also quite interesting to see that the paper clearly pushes 3G’s advantage over WiMAX, i.e. combined broadband Internet and voice telephony service with one infrastructure and lays out it’s arguments accordingly. A similar paper from the WiMAX industry laying out their arguments so one could compare would be nice. If you have seen one, please let me know.

Bluetooth To Use Wifi As A Physical Layer?

Bluetooth’s had a speed dilemma for quite some time now. After introducing new modulation and coding schemes with Bluetooth 2.0 already back in 2004 it seems to be impractical to push speeds beyond 2 MBit/s on the original Bluetooth physical layer. A speed upgrade, however, is direly needed as file sizes of photos and videos grow. Also, network speeds of HSDPA and EV-DO networks already surpass Bluetooth 2.0 speeds, thus rendering it unsuitable as a technology to connect notebooks to phones for high speed wireless Internet access.

In 2005/2006 the Bluetooth Special Interest Group (SIG) decided to use the Ultra Wide Band (UWB) standard of the WiMedia Alliance as a phyiscal layer. Up to today, however, standards have not been published and no devices are in sight. Instead, it is now rumored that the SIG has started talks with the 802.11 working group to also use Wifi as a physical layer for future Bluetooth versions.

The rumors are spread by two reliable German technology and telecommunication magazines, Heise News and Teltarif. Unfortunately they are only quoting "well informed circles" and do not give any references for their claims. The English speaking world seems not to have picked up on it so far, my Google search came up empty. If you’ve seen this rumor somewhere else, please leave a comment with the link.

Too little too late?

I wonder if faster Bluetooth is still needed as other wireless alternatives are already on the market today. Many phones such as Nokia’s N-Series phones (think N80, N93, N95…) have Wifi on board, as have many Windows Mobile PDA’s. These devices could use their wifi chips in access point mode as suggested here to offer notebooks (plural!) access to the Internet via their fast HSDPA or EV-DO chips. As far as I know none of these devices actually allow this today but the hardware is in place. No need for an extra Bluetooth stack on top.

For other uses such as large picture and video file transfers other alternatives that use Wifi are already available today as well. Nokia has put Universal Plug and Play (UPnP) into some of their N-Series phones to connect their devices to the digital home.

If Bluetooth wants to play a role in this market in the future the SIG has quite some catch-up to play or else Bluetooth will be doomed in the future as a technology for wireless headset connection and as slow data exchange protocol for small files.

Mobile Data Roaming Charges On The EU Watchlist

Dean Bubley over at "Disruptive Wireless" reports from the Mobile Broadband Congress in London that a policy maker from the European Commission said in his keynote speech that wireless operators should not only think about voice roaming prices, which will soon be regulated, but they should also start thinking about consumer friendly data roaming prices if they want to keep the EU from repeating the regulation exercise:

"He pointedly remarked that the new regulations task national regulators
with "monitoring" both voice and data roaming, and that everything
would be reassessed in 18 months’ time."

18 months is a long time from a consumer point of view (i.e. ME) but let’s hope operators start that "thinking process" rather sooner than later.

For the moment, only few usable offers exist for international data roaming:

Vodafone Germany’s WebSessions for 15 Euros a day work quite well for business travelers but the offer is way too expensive for the average consumer or for only checking eMails and news every now and then on the mobile phone while in another country.

A great alternative and good example for other operators is "3", if you happen to live in a country with a Hutchison "3" network and travel to other countries with a "3" network. Basically they have scraped roaming charges for both voice and data altogether. Just too bad they are only present in a few countries.

When traveling to countries such as Germany, Italy, Austria, the U.K. and Spain, prepaid SIMs are also a good alternative. Here’s a list of countries and operators that offer mobile Internet access via prepaid SIMs.