Friday, June 17, 2011

Doing away with Docomo data

As many of you are probably aware, I have been testing a prepaid b-mobile Fair SIM, that gives me 1 GB of data to use over 120 days (approximately 4 months). This is in addition to my normal Docomo service plan, so I use two devices, one for voice (Docomo ht-03a) and one for data (Google Nexus One).

My Docomo voice plan costs me just under 2000 yen per month, and if 1 GB lasts me the full 120 days, I would pay just over 2000 yen per month for data. At the Fair SIM recharge rate of 8400 yen per gigabyte, this would work out to 4000 yen total per month. This is about half of what I normally pay.

One month ago, based on only two weeks worth of usage data, I attempted to predict how much, if any, of my b-mobile Fair SIM charge would remain on 8/10/2011, exactly 120 days after activation. It appeared that about half would be remaining. Now that I have twice as much information for the calculation, I get essentially the same answer.

So I am now convinced that one charge, on average, will last me the full four months. Without the use of wifi at both home and work, however, it would not be possible.

Before the start of next month, I will cancel my Docomo data plan for the ht-03a, which scales from 372 to 5985 yen. I considered subscribing to NTT East's Flet's spot wifi service, which has seemingly good coverage, includes all the train platforms I use, and costs only 210 yen for month for Flet's home internet subscribers, until of course I saw that for some asinine reason, it uses PPPoE authentication, ruling out usage by both iPhones and Androids. (And check out the setup guide! [PDF, J] WTF? It's wifi folks, you don't need MAC address registration, plus PPPoE authentication, and a dedicated client.)

Next, I will begin looking into the feasibility of a VoIP solution for voice, so that I can do away with carrying two phones. My gut feeling is that due to the family plan, it is probably not worth canceling my Docomo service all together. But rather than guess, I can easily use the information available in my monthly statements to calculate what I would have paid if I was using BlueSIP or b-mobile VoIP, similar to how I did here.

Here is another over complicated chart. Feel free to stop reading now.

I started using the SIM on April 12th, a few days before they went on sale. I really put it though the ringer, so to speak, at first, burning through data with skype and youtube and whatever I could think of. The Fair SIM, unlike the Aeon "Plan C" SIM (which is 4980 yen for 1.2 GB per month) is wide open and does not pass through a proxy, so I can basically do whatever I want with it (except for p2p, which I don't use anyway).

Based on my usage since Golden Week, I predict that I will have 400 MB remaining when the charge expires on August 10th. To take into account the time I didn't use the SIM, I recalculated based on an expiration date 120 days after Golden Week. This results in 300 MB remaining. (The initial heavy usage partially offsets this, but not entirely, because the blue line passes through the top of the graph on the left side; 100% offset would result in the line passing exactly through the top left corner.)

My prediction doesn't significantly change if I use only the latter portion of my usage data. Doing so is justified by the apparent trend in my daily bandwidth consumption (green line and dots). As I became accustomed to how much data my daily activities consumed, I began caring less and less about how much data I was using. Now, the only thing I do differently than before is avoid viewing pages with lots of high quality images and updating market apps over wifi instead of whenever I got an update notification.


  1. afaik plan c does not use a proxy. i don't have a proxy registered in the apn, and i get data ok.

    probably a and b plans use a proxy to speed up the connection (some form of compression).

  2. You are thinking of something a little different.

    The proxy would be on b-mobile's side, not something you set. It would be just like using your LAN at home, where you would have a private IP of 10.x.x.x or 192.168.x.x, but this is not your real, external unique IP. Download My IP and check to see what you internal and external IPs are. I bet they are different and the internal IP is something like 10.x.x.x and the external is 210.128.16x.x

    If not, thought, that is great.

  3. I am currently using Mopera U standard with the public WLAN option (MZone) and pay 840 per month. However, I've seen that public WLAN seems to be also available for sp mode (315 Yen/month). I do not know which one would be cheaper (MoperaU + Public WLAN  or sp mode + Public WLAN).  I will stop by at a Docomo store this weekend and will check it out.

  4. SBS, why don't you use an unlocked portable wifi router with the b-mobile Fair SIM so that you can use voice and data on one phone. You would still have to carry two devices, but could enjoy the benefits of a smartphone instead of having to switch devices. Downside is that the battery life of a wifi router is most probably not as good as your 'data phone'.

  5. Thanks for pointing out that app! I'll look into it. If it works, that could be a fix. Unfortunately, there is only one comment in the Japanese android market and it just says force close.

  6. You're right about battery life. The routers can't last a day. A phone can, though just barely. The HTC magic is small enough that it is not an issue to carry around in the same pocket as the nexus. If I can find an old mini-phone from docomo for free, I'd switch to that, though I might lose it because of it's size. ;-)
    Most importantly, and this applies only to the Fair SIM, is that I have several apps set to sync only on wifi to save bandwidth, like my RSS reader. If it is constantly downloading new articles with images, that would seriously eat bandwidth. Since there is no way to differentiate between wifi through a traditional internet connection and wifi through a mobile router using the SIM, I'd have to completely disable background data on those apps and sync everything manually.That would be too much of a lifestyle change to justify being able to use have voice on the nexus one. I get where you're coming from, though.So yeah... two devices is not ideal. That is for sure. But for half off my bill and being able to use the handset of my choice on Docomo's FOMA network for data, it's worth it.

  7. i got an ip of so looks like a regular ip address...

  8. ?? That IP address belongs to a hosting company in Santa Clara CA...? That was the external IP? on mobile data, not wifi, right?

  9. A quick question on Docomo data rates.  So on the packet-houdai plan, you still have to pay an extra 4,200 on top of that to tether correct? After that is it still unlimited data on tethering? Anyone know about this? I can't get on my office network with my laptop, and I am planning on buying a Galaxy SII next week.  So my question is would i be able to tether my laptop through my SII, and by only paying that extra 4,200 have unlimited data still?

  10. Techniker TechnologeJune 18, 2011 at 11:45 PM

    if you have
    - a phone with IMEI registered by docomo (i.e. bought from docomo),
    - set the unlimited apn,
    - patched it's android version to support tethering
    and if you don't overdo the tethering, then you should be able to get away withought paying the extra 4200 yen.
    At least that is my experience (HTC Magic from Docomo with TMUS/Cyanogenremix and tethering once in a while, except for one month alway way below 1gig/month).

  11. ht-03a→atrix tokyoJune 19, 2011 at 11:24 AM

    I'm right behind you...さよならnttドコモデータ...thanks for much for your excellent coverage on the other options out there.
    After finally saying goodbye to my HT-03a (who may be back in action soon as a calling-only device!)  I've been attempting to use an unlocked (sim-free) motorola atrix with my same contract (pakehodai double).After a week of pulling down data at 128kbps from the apn non-Docomo phones are delegated to use I have to report: it's not a nice place to be! B-mobile Fair sounds like the next step.I've been following your report on these issues, so I kind of (but not completely) knew what I was getting myself into...nevertheless, I thought I'd play it out a bit and see what happens when you try to use an unlocked phone...ahhh! I now see! After all this I went in to the Docomo shop yesterday to make a "complaint" pointing out these two points:1. They big announcement that Docomo is "down" with use of unlocked phones isn't justified if they can't offer a reasonable data plan for such users. directly said: open up either or or for unlocked phones and let us use it for the same rate you contracted us for in the first place! I also asked "Why?" unlocked phone users will need to pay 4,000 yen more a month for the same service...Of course, they don't have a clear answer...I guessed that it is because they aren't receiving income on the sale of a new docomo-branded phone? The staff smiled. I finished by quoting estimate prices for b-mobiles fair service...which, come to think of it, will profit ntt docomo as b-mobile is paying to use their network...なるほど!2. That the staff needs to be trained better (at all?) on set-up instructions for unlocked phones. When originally setting up my phone I called the technical support line: they told me to use  told me to set the phone to or - it works for one connection, then cuts off immediately...Then when i went to the shop the staff told me I could simply use or and that it would be OK with my pakehodai plan - I pushed him on this with a lot of 絶対にs - eventually he ended up with a かもしらない・・・I demanded that they at least take off the charges incurred when the STAFF MEMBER HIMSELF (!) set my phone to use the apn. Eventually he realized that the 128 zone was a safer spot...he still wasn't sure so he suggested that I use the mydocomo app to monitor my charges...the place issuing the charges doesn't know how they will charge?Might I suggest a sub-name for blog: Docomo Sucks, too...

  12. Don't you love it when disqus decides to remove all line breaks? It is easy to find where they should have been because there will typically be no space after a period.

  13. ht-03a→atrix tokyoJune 19, 2011 at 3:32 PM

    thanks for adding those breaks! btw, do you know of a place where i can test the atrix with b-mobile before buying the sim? yodobashi in shinjuku was pretty clear that there's no guarantee that it will work...seems like it should, though...but just to be safe...

    Also...are you using google contact sync still with your ht-03a to deal with contacts?

    playing around with the idea of going "all motorola" with this: - pretty cheap on yahoo auction...

  14. oh, i was using opera mini which has a proxy built in. i used the native browser and did an ip check and it came back with a which is in japan.

  15. Sorry, I wasn't clear. I meant to say that you should download the app called My IP
    And use that app to check your IP.

    Using the browser won't tell you if you are behind a proxy. It will just report what your external IP is.

    Is your internal IP different from you external IP?

  16. Re 1: is already open. You can set it right now with your atrix, but it will cost you an additional 4200 yen. In reality, nothing changed on April 1. We were always able to set and use asfaik.

    Regarding NTT Docomo profiting from b-mobile; yes, this is true, but they do not want MVNOs operating on their network like this, with the details transparently available (on Docomo's own site) for all to see. This was essentially forced on Docomo. It went to arbitration with the MIC. The result was FOMA being opened for anyone to use as an MVNO. Here's the main link on NTTDocomo's site:
    And here is a PDF with all the prices that MVNOs will pay:

    Re2: I had a similar experience. The guy at the shop set an APN and it cost me money. Getting it back was difficult because 1) He read me the disclaimer saying that I could incur additional expenses by using an non Docomo phone and 2) there was (apparently) no way for them to credit my account. 

    As far as the disclaimer, I acknowledged that I was told using my nexus could cost me more money, but I pointed out that I never used it. He did. I pointed out that I never asked for the nexus to be set up, but instead I asked if it could be used and for how much. The answer to that question would determine if I would go forward and use my phone.

    But as you noticed, because Docomo corporate has circulated fuckall in the way of information to the shops, they don't know what they are doing and can't answer the simple question of how much. This is not the shop's fault. When I suggested that the shops needed to demand more info from corporate, the guy (assistant manager of that shop) just snorted and was like "yeah right, like that's gonna happen... Corporate's stance is that we're lucky to be allowed to work under the great docomo name and we should be happy with what we get."

    In the end I got my money back, but it was straight out of the assistant manager's pocket. I even provided him with a 領収書. How's that for fucked up?

  17. Many of us have been there already. Frustrated with Docomo's arrogant attitude and incomprehensible practice of locking out Non-Docomo phones. The Docomo shop staff is simply not trained for any non-standard situations like a Gaijin walking in with a legally unlocked phone trying to make it work on the Docomo network.
    I tell them right into the face that they are filtering IMEIs, charging outrageous fees for unlocked phones, other ridiculous fees (e.g. cancellation fee of 9,800Yen) and that many competitor services (WiMAX, b-mobile, etc.) are cheaper. They couldn't care less... Always smiling and following the manual.  I gave up (for 99%) and try to reduce the money I pay to Docomo by using other services and cancelling all services and options with Docomo that I do not really need. 

  18. Agreed .. However they do have one of the better networks.. .
    At the moment I have 2 phones,my private iphone 4 on Softbank and my offices mobile on DoCoMo .. can you guess which one cuts me off in the middle of a call and I'm in the center of fraking Tokyo
    All I want is a simple plan  + 1Gb of data to do with as I want... no extras for tethering

    Softbank's data network is a joke .. my old 3G iphone was jailbroken and I installed MyWi on it pages took forever to load and failed most time

    Just looking for a simpler solution

  19. @Joedarkside
    Agreed as well. I also have a Softbank phone (iPhone4) at work and my private iPhone on Docomo. The Softbank network sucks in terms of speed and coverage, that's for sure.  I only want Docomo to drop IMEI-filtering and allow Non-Docomo phones to use the 5,985 Yen flatrate. Although I think that it's not cheap as it does not allow tethering, I would accept it.  Let's hope that corporate Docomo will have this insight soon...

  20. Everyone should keep in mind that, even if Docomo does get reasonable with the bizho APN prices, there is still going to be one HUGE problem. The lack of MIC certification of most of the handsets you'd want to use on Docomo. Even if they are certified, some, like the N1, don't actually have any of the necessary markings to prove it.

    So even if Docomo provided a means for staff to register IMEI numbers for access to the bizho APN, you'd still be out of luck with just about anything brought from overseas (except an iPhone).

    But softbank is helping matters by announcing they will allow unlocked phones for 5985 yen
    Softbank SIMs for unlocked phones from July

    This will help more than any complaining that we could do.

    My guess is that Docomo will never open the bizho APN but instead will eventually create a new that bills per the GB.

  21. I agree that Softbank's move to allow unlocked phones to be used on their network is putting some pressure on Docomo. However, I am reluctant to move to Softbank as I know the speed of their network from my company iPhone.
    You could be right that Docomo  might offer a plan in future that bills per data volume, but I don't expect that this plan will be cheap as such plan should  allow tethering. If you look at their corporate presentations, you can see that one of their declared goals is to increase the ARPU (average revenue per user) by pushing customers to use more of their data services.

  22. Yes i think the best move would be to create a new APN for the non-Docomo IMEI's and allow a flat or  allocated amount of data

    In fact I like the samsung Sc-02C but no way will i pay 4200 for tethering

  23. Agreed that this is their goal, but isn't this the goal of all MNOs? Or MVNOs for that matter. Or any company?

    My guess is that it would be offered for the same price as their unlimited plan, 5985. It would be a totally reactionary to an actual or perceived loss of customers customers to (MVNOs or SBM). There could be image concerns as well.

    And if someone really chews through the data one month, It only takes 2 GB to be over the current price for unlimited tethering. Xi, is billed at about that price for 5 GB, so at that price for 1 GB is a good price point for Docomo.

  24. I like the way that @e5f54e56221e9a3b19f91603e6b9772f:disqus put it: "patched it's android version to support tethering"

    Samsung provided the cyanogen mod devs who are maintaining the galaxy version of CM 7 with free brand new SGSIIs for the purpose of getting them working flawlessly with CM7.

    The popularity of the SGSII with readers of this blog will by all means depend on if it has an unbeatable bootloader...

  25. Which APN are you using for tethering?
    What happens if you exceed 1GB? I am asking as I have the same phone (HT03-A unlocked & CM 6.0 (TMUS-32B-Froyo-CM6Remix)).

  26. DoMoDoMo , probably that is the one he is using. That is the one I used and most of have used. Exceeding 1 GB is not in and of itself going to necessarily be a problem. People consume that amount easily with just their phones if they download lots of podcasts and use youtube.

    Somewhere buried on this site in regards to the Xi LTE data cap of 5 GB is a quote from Docomo CEO Yamada saying that 95 or so percent of FOMA users are under 5 GB per month, which is why they put the cap (or the point at which they start charging for more) at 5 GB.

    So, personally, 5 GB of usage was what I considered to be an excessive amount. However, always use tethering sparingly if you are not specifically paying for it. And I should reiterate that the most amount of Docomo data I've ever used in one month was about 600-700 MB.

  27. SBSdroid I did think about this but it's seem that hardware accelerated support isn't enabled in the CM7 at the moment hopefully it will be enabled  soon

  28. ht03a→atrix tokyoJune 21, 2011 at 11:06 PM

    SBSdroid - I don't quite understand the legal implications involving Docomo allowing usage of their "all-you-use" referenced this above with your comment about MIC certification and also in your post on SBM's sim-card offerings:
    "Don't blame SBM for this, it is simply the law. If Docomo were to allow unlocked phones to access the packet houdai APN for only ¥5985, you can be sure that if your phone is not officially marked as certified, that you won't be getting that price."
    If this is the case, I don't understand how Docomo can allow me to access their network using the APN in an "all-i-can-use" way, but not the faster APN...can you please explain?

  29. The difference would be passively allowing you to use your atrix with the open APNs versus actively registering your IMEI number in their database for use with mpr2.bizho. Since nothing has to be done for your phone to work with the 128 k or mopera APNs, they can easily look the other way. (It's also possible the staff are just uniformed.)

    JCI has done their due diligence wrt uncertified phones - it says on all the b-mobile pages that the SIMs can't be used with any phone that doesn't bear the MIC mark. But then again, b-mobile doesn't have to actively hold the phone and write stuff down for it to work.
    Maybe SBM shops will look the other way, maybe not.

    Did you hear about the flap when the iPad came out and the head of the MIC bought one in the US to use in Japan, but the wireless radio wasn't certified? The head of the MIC breaking the rules. Was on NHK, great scandal and great free advertising for Apple.

  30. Techniker TechnologeJune 22, 2011 at 6:48 PM

    > Which APN are you using for tethering?
    yup. afaik any other and you risk either paying the 4200 extra, over even more.

    happens if you exceed 1GB? I am asking as I have the same phone (HT03-A
    unlocked & CM 6.0 (TMUS-32B-Froyo-CM6Remix)).
    as SBS posted here. Nothing happened, I just wanted to point out that, except for one occasion (that was the earthquake/genpatsu month) I never tethered excessively, thus pretty likely stayed "under the radar"

    btw concerning tethering with the new models,
    @ sbsdroid: Any news on how tethering is done on the new models?
    I just doubt that they allow tethering via, and then try to detect tethering afterwards to make ppl pay the 4200 extra. Very likely tethering is implemented by adding a custom docomo "feature", that switches to a different apn when activating tethering. Can you confirm that?
    Would be nice if me cheapskate can continue to skip the 4200 for the occasional tethering... :-)

  31. ht03a→atrix tokyoJune 26, 2011 at 10:58 AM

    Went to akihabara yodobashi to try out b-mobile fair with atrix - doesn't work. Found others saying so online so it looks like that options out. The 128k data flow is killing me! I have to do something:
    Thinking of either: 
    1. Starting a contract for the Flat Data plan with Docomo to get a sim for the atrix; put the docomo sim i have now back in the ht-03a for voice and cancel data for that sim
    2. Going wi-fi with a mobile wi-fi hotspot device...wimax? emobile? xi? - then I can still cancel docomo data but keep the sim-card with voice in the atrix

     anyone ve a better idea?

    If I do go, wi-fi, any suggestions on where to turn?

  32. @e15334aeb4a650dc42ccaa1f5270621c  Are you sure it didn't work? Just because it said it had no signal and no 3G, or an error popped when you tried to use the browser doesn't necessarily mean it didn't work. Often the SIM is actually working, even though it says it is not.

  33. ht03a→atrix tokyoJune 26, 2011 at 8:14 PM

    as per whether or not atrix worked with B-mobile fair:
    indeed, it didn't register or show "NTT Docomo" on the screen...nor was there a H (HSPDA) with up/down errorsthe browser didn't work, nor did the market...and the phone generated a "sim..." error (forgot what the error message said exactly)

    same report here:


    Didn't read this yet, but it is about unlocking the bootloader of your phone and updating to 2.3, which has fewer issues with b-mobile SIMs than 2.2...

  35. ht03a→atrix tokyoJune 27, 2011 at 10:05 PM

    Forget to mention before: the staff at the b-mobile counter at Yodobashi in Akihabara was totally aware of the SBS blog. I went to the site to check APN settings and they said something along the lines of: そうですね、外国人がやっている詳しいブログはよく聞いています・・・