Guest kam_ Posted March 30, 2006 Report Share Posted March 30, 2006 (edited) Well no GPRS isn't faster than 3g.. GPRS has a maximum theoretical throughput of 8x28800= 230.400 kbps. Theoretical because thats assuming all 8 GSM timeslots are alocated to GPRS on that cell. It would mean no voice calls on that cell, and you would also need to be alocated ALL 8 slots to get that throughput. TDMA (what GSM uses) is basically like: User 1 transmit for 20ms using 8 slots = 8x28800= 230.400 kbps User 2 transmit for 20ms using 8 slots = 8x28800= 230.400 kbps User 3 transmit for 20ms using 8 slots = 8x28800= 230.400 kbps User 4 transmit for 20ms using 8 slots = 8x28800= 230.400 kbps User 5 transmit for 20ms using 8 slots = 8x28800= 230.400 kbps User 6 transmit for 20ms using 8 slots = 8x28800= 230.400 kbps User 7 transmit for 20ms using 8 slots = 8x28800= 230.400 kbps User 8 transmit for 20ms using 8 slots = 8x28800= 230.400 kbps User 9 transmit for 20ms using 8 slots = 8x28800= 230.400 kbps User 10 transmit for 20ms using 8 slots = 8x28800= 230.400 kbps User 1 transmit for 20ms using 8 slots = 8x28800= 230.400 kbps User 2 transmit for 20ms using 8 slots = 8x28800= 230.400 kbps etc In theis theoretical maximum for 10 users they get 8 slots alocated every 180ms, which allows them to transmit 230.400*0.02=4.608kb So if they transmit 4.608kb every 180ms, their average throughput per second is (1000/180)*4.608=25.600 kbps If there were 20 users they get to transmit every 380ms and so their average throughput is: (1000/380)*4.608=12.126 kbps As the users increases the time between when they get slots increases untill the TCP layer times out. With 3G the modultation used means you can transmit MORE than 28.800kbps. There are no timeslots because it uses CDMA and divides on code. This is far more complex for me to explain to you, but you can try to imaginee all the data is sent on the same stream and a code identifies who it belongs to. Its much more like your home network where you have the one connection and your ip identifies who is who. Its still time divided to some extent but the divisions are not fixed - this means if you want to transmit less than 4608kb for example the remaineder of the last timeslot isnt wasted. UMTS in its initial phase offers theoretical bit rates of up to 384 kbps in high mobility situations, rising as high as 2 Mbps in stationary/nomadic user environments. This is because there is some handshaking to say who transmits when, and its not fixed like in GSM. The closer you are to the tower the less flow control error and the faster you receive permission to transmit - The closer you are to the tower the higher the bitrate. 3G is geared more towards data and the standard even lays out a transition to packet based voice for 3G. (not VoIP because the IP layer is a waste of bandwidth, but similar). As for the personal service being faster.. Remember you're using the SAME cell and the same timeslots. Weather they decide to prioritise alocation to the 8.50 users is upto them - they may choose to do this because http users can hold off for longer without noticing. The point is simply that if you stream ALOT of data on the 7.50 plan they will stop you, on the 8.50 plan you'll pay $$$$ after you hit your limit. Either way they don't care - stop you, or make you pay above the odds. Edited March 30, 2006 by kam_ Link to comment Share on other sites More sharing options...
Guest kam_ Posted March 30, 2006 Report Share Posted March 30, 2006 Oh and since i've explained this much... my last example shoing how the time between when you can transmit increases as users increase... Although you may get 8 timeslots every x ms and the average throughput may end up higher than your voip codec, voip can only sustain a delay of about 600ms before it breaks down. So even if your using 13kbps codec, imagine there's so many users that you can only transmit every second. When you can transmit you can send 26kb which averages to 13kb per 0.5s. This may seem like it's fine for voip because your codec only needs 13kbs BUT the time between the packets is > 600ms and so the voice won't have got to the other end fast enough for it to be reconstructed. It'll sound choppy! This is exactly why voip over GPRS won't work unless your in an area where no one else is! You can try to improve the situation by making sure your codec frame and ip header fit inside 1 GPRS timeslot - which helps if you are only allocated 1 timeslot due to congestion. Another point... why TV over UMTS works but TV over GPRS doesnt... Its got less to do with bandwidth than you might think! With GPRS one mobile uses 1 timeslot, so multicast isnt possible - thats where you fire a packet out with multiple ip addresses for example. Everyone listens and if their ip is in there they decode the packet. So if 10 of u wanted to watch BBC1, i would fire out a packet of media with your 10 ip's in there. It's only cost me the bandwidth of 1 user not 10. With UMTS this is possible by coding the packet for all mobile users requesting BBC1. With GPRS it's not possible because only 1 user can every listen to one timeslot at any one time. I would need 10 timeslots - 1 to each user to transfer the media. Link to comment Share on other sites More sharing options...
Guest Confucious Posted March 30, 2006 Report Share Posted March 30, 2006 Kam_ I had a little knowledge of how it all worked but you have filled in some of the gaps - thanks! ;) Link to comment Share on other sites More sharing options...
Guest travisb Posted March 30, 2006 Report Share Posted March 30, 2006 travisb: There's a few with Co-Pilot left in stock. Why not nab one of those for the extra couple of bucks. ;) I'd need to flog the version of Co-Pilot for Smartphone AND Destinator PN for PPC first. Need to get em on E-Bay :roll: Link to comment Share on other sites More sharing options...
Guest Pagemakers Posted March 30, 2006 Report Share Posted March 30, 2006 Kam - do you a laptop? Which deal are you going for? As an aside, yes we have discussed the T&C's to death here, however, the average punter in the street is surely not going to know that on the 7.50 deal he "shouldn't" use a laptop. Link to comment Share on other sites More sharing options...
Guest DesireToFire Posted March 30, 2006 Report Share Posted March 30, 2006 Sorry to go a little off-topic, I've just gotten an MDA Pro on T-Mobile. I signed up to a flext plan and didn't add any internet allowance on when I signed up. I've logged into the My T-Mobile site and am having some difficulty finding any option to add an internet allowance or (hopefully) the new unlimited gprs. Would anyone be so kind as to point me in the right direction. Many Thanks. Link to comment Share on other sites More sharing options...
Guest Swampie Posted March 30, 2006 Report Share Posted March 30, 2006 Fleabag - is there any one from Tmobile looking at this thred who make the T&C's.... I just dont get why 1gb of http is fine while 1gig streaming is not ( or less for that matter ). May be throttling it would be a better option - most dont go that high any way. Its either a techincal thing or a way to reduce the actual 1gigs been used. <{POST_SNAPBACK}> HTTP is, in general, an intermittant connection. You request a page, read it, request another. This means that time slots used for GPRS aren't constant, allowing more calls to still be made on the local cell. Things like streaming give a constant, relatively high bandwidth usage. This means that the GRPS slots required are constant, reducing the number of calls that can be made on a cell. Streaming, to the network, is probably no different to downloading a large file via HTTP (which is allowable on the handset) - however, many people listen to steaming radio for hours on end, whereas most downloads, even via GPRS are probably in the <10 minutes category. Similarly, connecting via a laptop is *likely* to generate greater usage than through a handset. On a handset you're probably looking at email and a single web connection (unless you use Opera and multiple windows etc). On a laptop, if you're like me, you probably load up a few pages at a time and read them as the others are downloading. You also probably have other things in the background, all trying to download stuff - DigiGuide downloading TV schedules, Skype, Trillian (ICQ/IRC/AIM/MSN), anti-virus updates, Outlook calendar syncing, even Windows update. All these things can and do make laptop access a more constant and consistent consumer of GPRS (for most people). It's easier for them to say - no laptop access - than to say to turn everything off on your machine which might suck network usage. As I see it - T-Mobile are attempting to create a product £7.50 per month which gives you practically unlimited downloads, as long as your GPRS connection is not constantly active. There are only so many timeslots a cell can provide - these are used for calls and data access. If a data connection is constantly in use, then fewer timeslots are available for calls. If a data connection is intermittant, there are far more timeslots available for calls. To put it another way, a number of GPRS users who are downloading constantly (ie. using all timeslots available to them), will at some point, cause the cell to reject calls - both incoming and outgoing. T-Mobile are trying to avoid this - but it appears that for £10 (£8.50 + VAT = 33% premium over the £7.50 service), they're willing to allow you to have a GPRS connection with is constantly active. Link to comment Share on other sites More sharing options...
Guest kam_ Posted March 30, 2006 Report Share Posted March 30, 2006 Kam - do you a laptop? Which deal are you going for? I could potentially use things like VNC on my phone. I'll most likely be going for the 7.50 plan until they give me trouble. At which point i'll complain like crazy that there is no particular exception to that function. OR i may just VPN to my home network which will mask all my data. They may see high usage but there's no proof what i'm doing. It could be almost anything thats sucking up that bandwidth. The argument basically comes down to weather this data is really originating from my phone, and weather or not its any of the things mentioned in the T&C. Over VPN they can't track it, and my offical line will be "i can't disclose the exact app i'm using because of NDA's" ;) I'm also planning to check the feasibility of VoIP with a custom codec - i'll let you know what happens. But i don't plan to abuse the VoIP side of things - it will just be to connect to my PBX. If they want to give me trouble i can argue my way out of it very easily because i have yet to meet anyone on the CS side of things (including their 'technical team') who actually knows what they are talking about. The REAL engineers never talk to customers regardless of where you escalate it to. Besides i've taken them to adjudication and won before so they always get worried when they look up my account! I'm not really happy with a 2GB limit with the laptop line. Its VERY dificult to track usage acurately when your using alot of business services loaded on your machine. Put it this way, i get everything for half price so its £3.75 verses £5.00 - so there's even less difference for me BUT i'm still planning to try the 7.50 line first simply because of the limit Things like streaming give a constant, relatively high bandwidth usage. This means that the GRPS slots required are constant, reducing the number of calls that can be made on a cell. ... There are only so many timeslots a cell can provide - these are used for calls and data access. If a data connection is constantly in use, then fewer timeslots are available for calls. If a data connection is intermittant, there are far more timeslots available for calls. Typically some of the timeslots are allocated to GSM ONLY, and the rest may be alocated to GPRS only OR dynamically between GSM and GPRS (GPRS congestion doesn't really adversely affect calls, but it will affect packet delay for other users using GPRS in that cell.) For example (8 slots per frame - GSM): slots 1,2,3,4,5 for voice only slot 6 dynamic slot 7,8 GPRS only. 5 calls can DEFINATELY be active at any time (slots 1 to 5). The 6th call will connect if the 6th slot isn't allocated to someone on GPRS at the instant the call atempts its setup. 2 GPRS users can DEFINATELY be online with 1 slot each, or 1 user with 2 slots The 6th slot may ONLY be used when there isn't a call active on it You can expect if 5 calls are up the 6th slot won't be allocated to anyone untill the calls drop down to 4. Remember there are 8 slots PER frequency and you're phone can only lock onto one frequency at a time. BUT there are alot of frequencies on a cell - enough for hundreds of simultaneous calls. You would think thousands but it doesn't work like that. They make the cell smaller and add cells around it in more populated area's. That means more calls per sq mile, but the max number of calls in a cell are limited by the frequency use, which in turn is limited by frequency planning (cell structure of GSM required to get around the limited frequencies alocated in GSM). If you're interested/curious i can explain about that. :?: hung over ;) Link to comment Share on other sites More sharing options...
Guest Pagemakers Posted March 30, 2006 Report Share Posted March 30, 2006 Again a great reply Kam. Thanks. On the business tariff is it a definite cap. Ie 2.01GB and you're charged or is it just a fair use 'advisory'. Link to comment Share on other sites More sharing options...
Guest kam_ Posted March 30, 2006 Report Share Posted March 30, 2006 (edited) Again a great reply Kam. Thanks. On the business tariff is it a definite cap. Ie 2.01GB and you're charged or is it just a fair use 'advisory'. <{POST_SNAPBACK}> I'm not actually sure to be honest, i don't work there - i worked for a company which suplied their GPRS setup and GSM BSC's and BTS's. I do know they did have an 'unlimited' plan for tier 1 business with an 'uncapped' fair use limit for £40 worldwide some time ago. Now only those worldwide GSM tariff companies seem to do it tho. Edited March 30, 2006 by kam_ Link to comment Share on other sites More sharing options...
Guest shenson Posted March 30, 2006 Report Share Posted March 30, 2006 On the business tariff is it a definite cap. Ie 2.01GB and you're charged or is it just a fair use 'advisory'. I got the impression that 2GB was the only restriction in the FUP for the "Pro" version and that exceeding that would result in first warnings and then speed throttling. Just got my SIM only package today. Only trouble is that I've got to wait to receive the online PIN and I'm anxious to try it out. Link to comment Share on other sites More sharing options...
Guest Pagemakers Posted March 30, 2006 Report Share Posted March 30, 2006 (edited) Just been into my local (large) T-Mobile store. They confirmed the £7.50 tariff starting on Sat. "Can I use it with my laptop?" I asked. "Absolutely" came the reply. "Can I get 25% off for life in-store I asked?". "Yes" he said. "Can I use it for 3G?". "Yes" he said. "T mobile does not make a distinction between GPRS & 3G". ( I am with Orange and you need to be on a 3G tariff to get 3G). If they are unsure about the tiny small print then that's good enough for me. When I sign up with them on Sat I will ask again about the laptop thing. If they say yes for a second time I will use that to defend myself if T-Mobile slap my wrists for using my laptop in the future. BTW, 3 other people in the store with me were all Orange customers. T-Mobile said they had about 50 Orange customers in since yesterday! Edited March 30, 2006 by Pagemakers Link to comment Share on other sites More sharing options...
Guest Syphon Filter Posted March 30, 2006 Report Share Posted March 30, 2006 Just been into my local (large) T-Mobile store. They confirmed the £7.50 tariff starting on Sat. "Can I use it with my laptop?" I asked. "Absolutely" came the reply. "Can I get 25% off for life in-store I asked?". "Yes" he said. "Can I use it for 3G?". "Yes" he said. "T mobile does not make a distinction between GPRS & 3G". ( I am with Orange and you need to be on a 3G tariff to get 3G). If they are unsure about the tiny small print then that's good enough for me. When I sign up with them on Sat I will ask again about the laptop thing. If they say yes for a second time I will use that to defend myself if T-Mobile slap my wrists for using my laptop in the future. BTW, 3 other people in the store with me were all Orange customers. T-Mobile said they had about 50 Orange customers in since yesterday! <{POST_SNAPBACK}> Just to confirm, the 25% off for life is purely on the Flext and not the £7.50 data tariff right? Also, will they issue a USIM even if you are NOT getting a 3G device. I want to get a Vario for now, but want to make sure I get a USIM for when I buy a Hermes/Vario II/Qtek 9600. Link to comment Share on other sites More sharing options...
Guest rizzles Posted March 30, 2006 Report Share Posted March 30, 2006 Just to confirm, the 25% off for life is purely on the Flext and not the £7.50 data tariff right? Also, will they issue a USIM even if you are NOT getting a 3G device. I want to get a Vario for now, but want to make sure I get a USIM for when I buy a Hermes/Vario II/Qtek 9600. <{POST_SNAPBACK}> yeah you will get a USIM Link to comment Share on other sites More sharing options...
Guest Fleabag Posted March 30, 2006 Report Share Posted March 30, 2006 (edited) Page: I have posted the fair use policy - laptops are clearly not permitted. I'm not saying don't do it - that's up to you. But who are you going to believe? Me, independant with no agenda - or a salesman who can hear echoes of "kaching" in his ears as you and the rest of Orange walk in through the door of his domain. There's a reason there's a department in CS to support store staff... No amount of complaining is going to change the policy or how you've been treated, the "the guy in the store said..." line will make no difference - unfortunitely it is your responsibility to be aware of the fair use policy - it is not the network's responsibility to make you aware of it. Syphon: You will get the 25% off the data, provided you connect to the WNW version of Relax or Flext. You will NOT get the discount by connecting to a Relax or Flext plan and adding a WNW bundle. Edited March 30, 2006 by Fleabag Link to comment Share on other sites More sharing options...
Guest Pagemakers Posted March 30, 2006 Report Share Posted March 30, 2006 Hmm I guess you're right Fleabag. It's not the cost that concerns me it's the fixed cap on the business as opposed to a recommendation on the personal tariff. Link to comment Share on other sites More sharing options...
Guest brownjl Posted March 30, 2006 Report Share Posted March 30, 2006 Hello, When will us current web and walk users be able to take up these new tarrifs deal? On the 1st of April? My Monthly billing date is the 1st of the month :S does mean I am going to have to wait till the 1st of May to be switched over ;) Is it worth a call to CS tonight to see if they can have me put on one of these from my next billing date i.e. the 1st of april??? Cheers, James Link to comment Share on other sites More sharing options...
Guest kam_ Posted March 30, 2006 Report Share Posted March 30, 2006 (edited) ...unfortunitely it is your responsibility to be aware of the fair use policy - it is not the network's responsibility to make you aware of it. Actually that's not true. It IS the networks reponsibility to make you aware of it. This has been tested already with the adjudicators. That's why they plaster FAIR USE all over the place. If you were told something different by a T-Mobile representative - this can be a sales person in a t-mobile authorised shop - and you were never pointed to the fair use document online or otherwise, you would have a very very good case. For example i couldn't start up selling burgers and put an asterisk next to the price saying conditions apply, but not produce the conditions to you. Simply stating conditions apply just isnt good enough these days, tmuk as a network have to show they did everything in their power to make all the information redily available. Saying its on the net isn't good enough If i walk into a store and get misinformed, and never given any document highlighting the FU policy then TMUK can not uphold any clain based on it. Edited March 30, 2006 by kam_ Link to comment Share on other sites More sharing options...
Guest Pagemakers Posted March 30, 2006 Report Share Posted March 30, 2006 Agreed! At the worst I would have thought they do would be to move me to the business plan. Link to comment Share on other sites More sharing options...
Guest Pagemakers Posted March 30, 2006 Report Share Posted March 30, 2006 Oh and I also asked if you would keep the 25% discount if you changed tariffs. He said providing you don't go below your initial tariff to gain the discount then yes. So if you are new to T-Mobile it's probably best to go for a lower flext tariff and raise it later (you can do that at any time). remember though, the lower the tariff, the more expensive the phone (although there's no real difference between flext 30/35 phone costs). Link to comment Share on other sites More sharing options...
Guest pjam001 Posted March 30, 2006 Report Share Posted March 30, 2006 (edited) So the risk for people who havn't used much data in the past is that you join on a wnw flext deal and get 25% off everything, only to find that you don't use much data but have to remain on a higher rate tariff to keep the 25% off. Taking out a normal flext deal at 25% discount, then adding a £7.50 bundle allows you to remove the bundle at any time without losing the original 25% disount. Flext 25 = £18.75 (25% off), £24.38 (25% off flext&wnw), £26.25 (25% off flext only +£7.50 wnw) Flext 30 = £22.50 (25% off), £28.13 (25% off flext&wnw), £30.00 (25% off flext only +£7.50 wnw) Have I got this right? Cheers Edited March 30, 2006 by pjam001 Link to comment Share on other sites More sharing options...
Guest Syphon Filter Posted March 30, 2006 Report Share Posted March 30, 2006 Syphon: You will get the 25% off the data, provided you connect to the WNW version of Relax or Flext. You will NOT get the discount by connecting to a Relax or Flext plan and adding a WNW bundle. <{POST_SNAPBACK}> Fleabag: Sorry for asking stupid questions...but I'm a bit confused... what is the difference in price/features between getting Flext and getting the data as a bundle and getting flext on a WnW plan? Also, any word on the Vario II? Link to comment Share on other sites More sharing options...
Guest shenson Posted March 30, 2006 Report Share Posted March 30, 2006 Hmm I guess you're right Fleabag. It's not the cost that concerns me it's the fixed cap on the business as opposed to a recommendation on the personal tariff. <{POST_SNAPBACK}> Well I was told the 2GB on the business was FUP and not a case of being charged after that, just the usual warnings route. I was also told the personal didn't have a data limit, though the usage restrictions add an effective limit. For my usage 2GB is a hell of a lot ;) Link to comment Share on other sites More sharing options...
Guest rockykabir Posted March 30, 2006 Report Share Posted March 30, 2006 Fleabag: Sorry for asking stupid questions...but I'm a bit confused... what is the difference in price/features between getting Flext and getting the data as a bundle and getting flext on a WnW plan? <{POST_SNAPBACK}> Your query had been answered in the previous post ;) Flext 25 = £18.75 (25% off), £24.38 (25% off flext&wnw), £26.25 (25% off flext only +£7.50 wnw) Flext 30 = £22.50 (25% off), £28.13 (25% off flext&wnw), £30.00 (25% off flext only +£7.50 wnw) <{POST_SNAPBACK}> Link to comment Share on other sites More sharing options...
Guest Syphon Filter Posted March 30, 2006 Report Share Posted March 30, 2006 Your query had been answered in the previous post ;) <{POST_SNAPBACK}> Indeed it has...I hadnt seen that when i posted. But the Vario II question stands. Link to comment Share on other sites More sharing options...
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