They're fine with the RAID it'll work regardless if Intel or PPC chips but if they got 3yrs out of a 1U server that's not a bad deal. After all they can depreciate that hardware and typically business will do no longer than a 36 month lease on computer hardware because in fact most hardware is on the poor side of the value curve beyond 36 months.
I must be the only person who remembers when Apple equipment not only lasted longer than other equipment, but you could upgrade the software for a much longer time. I have two blue and white g3 towers running 10.4.11 with no problem, and three G4 towers running Leopard. These machines are far older than the G5 Xserves.
Apparently I'm the only person who just doesn't feel it's time to dump hardware, and at a time where most companies would be willing to spend $129 but not $5k, Apple is leaving a lot of money on the table.
Apparently I'm the only person who just doesn't feel it's time to dump hardware, and at a time where most companies would be willing to spend $129 but not $5k, Apple is leaving a lot of money on the table.
Agreed and I don't think that this is anything more than an anomoly. I think Apple will go back to supporting their computers for 5 years. What makes the PPC transition hard is that it's so close to the OS X transition. This behaviour is atypical of Apple IMO but I understand a bit why they are doing it.
Apple has shipped some of the buggiest software that I can recall in the last few years. I think kudos have to go to their engineers who bust their asses to keep the system stable despite Carbon/Cocoa battles and PPC/X86/ARM targets.
bbwi - Apple did license ActiveSync - more than a year ago. That support is coming for Mac OS X in Snow Leopard, as is mentioned in this article and during the WWDC keynote last year. But that is just Apple making OS X a first class citizen for businesses. MobileMe gets a lot more things right than it does wrong. The fact that sync from the MobileMe cloud to my iPod touch is pretty quick now, usually between 5 and 10 seconds, tells me they are heading down the right path. My understanding is that Snow Leopard will address this in the desktop client. I can only assume that syncing to the cloud will subsequently improve on both the desktop and the mobile device too.
I guess I wasn't clear. I am aware that Apple has licensed ActiveSync but they licensed it for the iPhone, not MobileMe. An iPhone can connect to an Exchange environment through ActiveSync but connecting to MobileMe using ActiveSync is not possible, which is what I was getting at.
AFAIK, Snow Leopard will not include ActiveSync but rather a customized solution using RPC over HTTP(s) just like Outlook can for Windows. This is different than ActiveSync
At the risk of beating this topic to death, I have to follow up on my post from yesterday with all of these NEW features requiring an Intel machine.
What Apple is saying here is that if I have workers with G4 laptops, G5 towers or iMacs, and ANY kind of iPhone . . . I can't push my data to them unless I invest in an Intel based server so that I can install Snow Leopard server. What does this "push technology" have to do with the damn server processor?
Or you can buy Kerio Mail Server today and get excellent ActiveSync and CalDAV support -- better than Leopard Server IMO. Email, calendar items and contacts push out to iPhones without any trouble at all.
The server runs just great on PowerPC Macs and under Tiger.
So called "push" notification has always come across as a bit of fiction to me. If my device is sleeping, there is no magical way a remote server can wake my device and force a message upon it. Somewhere underneath the hood, the device is waking up, connecting to the server and accepting messages. The rest is just media hype.
On a phone the device will wake up the baseband portion to do some kind of ping notification to the central server over a control channel. This channel is also used for text sending and receiving. And in Blackberries, for sending push messages. I presume that unless Apple do the same, then yes, it's not push because most phones try not to wake the main CPU up unless something has occurred.
With the full networking ping, Apple would need to wake up the main CPU and systems, make a network connection to their servers (this takes a bit of time of course), send the required ping messages, and get the responses. This isn't push by any definition, and it also uses up a lot more battery power.
More than likely Apple is going to integrate into the control channel a small message that encodes the application name and a quotient and maybe a tiny message. Then if this occurs the baseband can wake up the main part of the phone to do the bigger data gathering or just handle the control channel message.
No, you can't stream Pandora with the latter. I hope that if the phone is awake, then more adventurous push updates and background apps will eventually be allowed.
So who gets to define "sleep"? A sleeping computer can still receive key and click signals, USB connections, ethernet wake signals, IR remote signals, Bluetooth signals, etc.
I don't believe that's true. I have NEVER seen the update badge pushed to my iPhone (and I do have Push enabled--Yahoo uses it). The only time I ever see a number on that icon is if I launch the App Store. (I don't have to go to Updates, just launching into any part of the store is fine). Then, when I exit, any updates I haven't downloaded get counted in a badge.
But if I never launch the App Store, I never see any update badge. That's not push.
I agree. I never see the the badge update until I go into the app store to check myself. Or sometimes when I sync to iTunes it will show up. That is not push at all. And in this article when it references the Push notification of RIM and Microsoft lets not even go there yet please. First of all Push should have been out 2 years ago when the iPhone came out. The phone is getting old and it is too slow to do things as is. Push notification is far too late for the iPhone now. I am ready to toss my 3G Lag iPhone and get something new that can update freely without lag. AKA the Palm Pre. Something that can truly multi task. And before anybody says the iPhone will out perform any phone at all... How come it lags when I text message. How come it lags in google maps? How come it lags switching from contacts to recents within the phone app. This phone is too slow Push notifications now will only make it work. Please don't pretend this is a business phone. No Business has time to deal with this slow in affective micro computing these days. Maybe the Windows mobile phone isn't pretty to look and and maybe it doesn't have fun games. It gets the job done.... If you guys want to see a noticable difference in quality and crap compare the iPhone to the Black Berry bold.... the bold is FAST. Lag free. You can email, copy/paste and text as well as push notifications all without any lag.
I agree. I never see the the badge update until I go into the app store to check myself. Or sometimes when I sync to iTunes it will show up. That is not push at all. And in this article when it references the Push notification of RIM and Microsoft lets not even go there yet please. First of all Push should have been out 2 years ago when the iPhone came out. The phone is getting old and it is too slow to do things as is. Push notification is far too late for the iPhone now. I am ready to toss my 3G Lag iPhone and get something new that can update freely without lag. AKA the Palm Pre. Something that can truly multi task. And before anybody says the iPhone will out perform any phone at all... How come it lags when I text message. How come it lags in google maps? How come it lags switching from contacts to recents within the phone app. This phone is too slow Push notifications now will only make it work. Please don't pretend this is a business phone. No Business has time to deal with this slow in affective micro computing these days. Maybe the Windows mobile phone isn't pretty to look and and maybe it doesn't have fun games. It gets the job done.... If you guys want to see a noticable difference in quality and crap compare the iPhone to the Black Berry bold.... the bold is FAST. Lag free. You can email, copy/paste and text as well as push notifications all without any lag.
In a nutshell... don't give me push my iPhone lags enough already.
It will be awesome for Apple to really take-on Exchange. For SOHOs a Snow Leopard server that could host their email and push to iPhones, Blackberries, etc would be ideal and inexpensive since they wouldn't have to deal with CALs as they grow.
Mobile email is king and Exchange and RIM have that down pretty good. Hopefully Apple can pull this off right the first time.
Yeah, for the love of god why doesn't Apple just license ActiveSync? For that matter, why don't they scrap MobileMe all together and just partner with Google. I use MobileMe now but do not foresee any reason to continue paying $100 a year as soon as Gmail offers push email.
IMHO, Google is MUCH better, in every aspect, at delivering web services than Apple and there is no evidence so suggest that would change in the future.
Maybe it has something to do with them being a web company.
I agree. I never see the the badge update until I go into the app store to check myself. Or sometimes when I sync to iTunes it will show up. That is not push at all. And in this article when it references the Push notification of RIM and Microsoft lets not even go there yet please. First of all Push should have been out 2 years ago when the iPhone came out. The phone is getting old and it is too slow to do things as is. Push notification is far too late for the iPhone now. I am ready to toss my 3G Lag iPhone and get something new that can update freely without lag. AKA the Palm Pre. Something that can truly multi task. And before anybody says the iPhone will out perform any phone at all... How come it lags when I text message. How come it lags in google maps? How come it lags switching from contacts to recents within the phone app. This phone is too slow Push notifications now will only make it work. Please don't pretend this is a business phone. No Business has time to deal with this slow in affective micro computing these days. Maybe the Windows mobile phone isn't pretty to look and and maybe it doesn't have fun games. It gets the job done.... If you guys want to see a noticable difference in quality and crap compare the iPhone to the Black Berry bold.... the bold is FAST. Lag free. You can email, copy/paste and text as well as push notifications all without any lag.
That's my whole point. The phone is never really sleeping.
It's not quite true. While the *whole* device might not be sleeping, wake-on-interrupt type hardware systems allow hardware designers to make a device that is sleeping except for very specific portions of the circuit, while the rest of the circuit / device is in sleep mode. The device that's "listening" basically pokes the rest of the system awake only if it's needed. A polling system would not allow as much of the device to sleep.
Could somebody tell which protocol is used to implement the push technology?
It must at telecommunication level (GSM, 3G and more) , since the IP layer must be dormant when the phone is sleeping.
The comparison with the IM protocols in the article is not that good, because the the IM client has an active connection with the server, which is used for the push.
I'd just like to point out that this description of how email is currently working on the iPhone above is really overly "rosy" in that it makes it seem like it all works fine when clearly it doesn't.
...
For instance if the iPhone is turned off on your desktop and your local mail client is open on the desktop computer, the iPhone will have acquired the new email notifications as your mail is dealt with on the desktop computer during the day, but only by turning on the iPhone and starting the mobile mail client will it actually update your mail or fetch mail that hasn't been read. It also does not sync email in folders until you actually access that folder, it just focusses on the inbox so as to make it seem like your mail is all being synced. Worse, depending on your settings one often ends up with multiple copies of various inboxes outboxes etc. on your laptop, your desktop, your iPhone and your web client as well as copies of the copies. There is no way to get rid of them save manual deletion or manual resetting of your clients and mail settings.
If you TURN THE PHONE OFF there is no way it will get updates. May be you mean turning the display off? Do you have your push settings set properly on the computer and on the phone? Take a look at the advanced setting in the Fetch New Data on your phone.
As far as my sync experience is considered, I find the article pretty accurate. I have 2 IMAP and 1 exchange account on the phone and have no problem with the folder contents and marking the messages as read. If I open a mail application on my computer and read the new mail from the phone, I can see the mail updating the read status within seconds.
The folders, other than the inbox, are not constantly updated for purpose. This is a feature, not a bug. Most people rarely need to browse Sent Items, let alone deleted items. I would prefer to save battery life and 3G data transfer and not have these folders always synchronized.
Could somebody tell which protocol is used to implement the push technology?
It must at telecommunication level (GSM, 3G and more) , since the IP layer must be dormant when the phone is sleeping.
The comparison with the IM protocols in the article is not that good, because the the IM client has an active connection with the server, which is used for the push.
The iPhone doesn't sleep. The OS is always running. When there's nothing in the main event loop to run, the CPU goes off for a few milliseconds at a time.
I haven't instrumented an iPhone to measure, but with most similar systems: The baseband informs the main CPU whenever the cellular network sends it data. "Data" can be an incoming phone call, an incoming SMS, *or* an incoming IP packet.
In other words: incoming IP packets go straight to the OS, regardless of whether the system is fully operational, display off, or even asleep. You don't need to send continual packets to keep a link open. Once of my WinCE toys would actually fully wake up from sleep if you sent data over a TCP link.
TCP or UDP would be fine protocols to use for a push system with an architecture like the iPhone's. There wouldn't be additional overhead in terms of power usage.
That's my whole point. The phone is never really sleeping. It's still polling for messages. Messages still get queued. Now, you can correctly argue that this protocol is much lighter-weight and uses less radio time and power than setting up an IP connection and connecting to a mail server, but there's no magic "push" service that's saving battery by pushing out updates "immediately and only when necessary".
Quote:
Originally Posted by bbwi
No messages are queued with push. As soon as they hit your inbox they're pushed to your device (unless your device is physically turned off, then yes, they'd be queued). If there are no messages then nothing is pushed. In a pull method, you need to schedule your phone to check in intervals. If there are messages they will get queued until your phone wakes up and checks. If there are no messages then your phone STILL wakes up and checks. This is where the battery savings come in. When your device is checking for messages even when there are none.
I understand what PMJoe is talking about, and it always confused me as well. People keep talking about the client device not having to poll the server to get a new message, as it simply gets "pushed" to the phone. Well how the hell can the server "push" email notifications (or any other data)to the phone if the phone's TCP/IP data connection is not active??
The only way I can imagine this happening would be if AT&T (or whoever) itself had equipment that sent notifications through the minimal "heartbeat" signal that lets your phone and the cell tower communicate.. Is that what the Blackberry Server does? If so, then the cell carrier has to install special blackberry push equipment right?
Also, How does ActiveSync compare to this? If the Push email on ActiveSync/MobileMe doesn't use the special cell->tower signal, then it has to be using standard TCP/IP connections, and how is that any different than polling??
Can someone with a technical understanding of this please comment!
I understand what PMJoe is talking about, and it always confused me as well. People keep talking about the client device not having to poll the server to get a new message, as it simply gets "pushed" to the phone. Well how the hell can the server "push" email notifications (or any other data)to the phone if the phone's TCP/IP data connection is not active??
Ahh, well, what do you mean by "active"?
Inside an operating system, it costs nothing more than a tiny bit of memory to have an "open" TCP link. The CPU doesn't have to do anything until a packet actually comes in. It's really just a pathway, knowing which app is supposed to get the packet. If the app is written properly, it will use *zero* CPU until something happens.
That's all well and good, but the packet needs to get to the CPU somehow. That means you need to have the radio on, and in the right state.
The radio is already on, and already informing the cellular system where it is.
When you are sending IP packets to a cellphone, you send them to an IP address like any other. You don't do any magic to tell the cellular system where to send them.
So:
You start out with a live GSM network link. Your baseband is up and running, registered on the AT&T network. But you can't do data. The iPhone OS tells the baseband, "Please get me an IP address."
Baseband talks to the GSM network, gets an IP address, gives it to the iPhone OS.
Now IP packets can be passed over the link.
Once we are in this state, the cost to *remain* in this state is zero. AT&T knows where the phone is. iPhone knows its IP address. AT&T IP network knows that this particular IP address goes to this particular cell tower which then sends it to your phone.
In the case of the iPhone, which never actually *sleeps*, but rather shuts off the bits it doesn't need, it can get a new IP packet from the baseband whenever one comes in. Other phones that do sleep can get woken up whenever the baseband has a message.
iPhone logs in via IP to the push system, proves that it's my iPhone. Then it just sits there. Push system knows the IP address to send my messages to. No further traffic is needed at the iPhone OS layer.
Quote:
The only way I can imagine this happening would be if AT&T (or whoever) itself had equipment that sent notifications through the minimal "heartbeat" signal that lets your phone and the cell tower communicate.. Is that what the Blackberry Server does? If so, then the cell carrier has to install special blackberry push equipment right?
I don't know much about the implementation of Blackberry. They may also do different things with different models. I suspect that they send SMS or SMS-like messages. The carrier can do that quite easily if you're a big customer. It also ensures that you need a special data plan. The iPhone can do push with Yahoo, MobileMe and ActiveSync without the carrier being involved.
Quote:
Also, How does ActiveSync compare to this? If the Push email on ActiveSync/MobileMe doesn't use the special cell->tower signal, then it has to be using standard TCP/IP connections, and how is that any different than polling??
Can someone with a technical understanding of this please comment!
I'm pretty sure that ActiveSync is a pure IP based system. I've never seen any carrier-specific requirements for ActiveSync, There's no single, unified open standard for sending SMS messages to a carrier. Without carrier-specific agreements and integration into their system, you're gonna be IP-only.
I hope this makes sense. My personal background is primarily in the IP domain. I've worked with a lot of cellphone systems, but I've never actually built a GSM radio, or directly integrated my stuff with a carrier. If somebody here does know about the overhead of keeping a PDP context activated on a UMTS network, and there's more to it than I am aware of, please correct me!
Comments
They're fine with the RAID it'll work regardless if Intel or PPC chips but if they got 3yrs out of a 1U server that's not a bad deal. After all they can depreciate that hardware and typically business will do no longer than a 36 month lease on computer hardware because in fact most hardware is on the poor side of the value curve beyond 36 months.
I must be the only person who remembers when Apple equipment not only lasted longer than other equipment, but you could upgrade the software for a much longer time. I have two blue and white g3 towers running 10.4.11 with no problem, and three G4 towers running Leopard. These machines are far older than the G5 Xserves.
Apparently I'm the only person who just doesn't feel it's time to dump hardware, and at a time where most companies would be willing to spend $129 but not $5k, Apple is leaving a lot of money on the table.
Apparently I'm the only person who just doesn't feel it's time to dump hardware, and at a time where most companies would be willing to spend $129 but not $5k, Apple is leaving a lot of money on the table.
Agreed and I don't think that this is anything more than an anomoly. I think Apple will go back to supporting their computers for 5 years. What makes the PPC transition hard is that it's so close to the OS X transition. This behaviour is atypical of Apple IMO but I understand a bit why they are doing it.
Apple has shipped some of the buggiest software that I can recall in the last few years. I think kudos have to go to their engineers who bust their asses to keep the system stable despite Carbon/Cocoa battles and PPC/X86/ARM targets.
bbwi - Apple did license ActiveSync - more than a year ago. That support is coming for Mac OS X in Snow Leopard, as is mentioned in this article and during the WWDC keynote last year. But that is just Apple making OS X a first class citizen for businesses. MobileMe gets a lot more things right than it does wrong. The fact that sync from the MobileMe cloud to my iPod touch is pretty quick now, usually between 5 and 10 seconds, tells me they are heading down the right path. My understanding is that Snow Leopard will address this in the desktop client. I can only assume that syncing to the cloud will subsequently improve on both the desktop and the mobile device too.
I guess I wasn't clear. I am aware that Apple has licensed ActiveSync but they licensed it for the iPhone, not MobileMe. An iPhone can connect to an Exchange environment through ActiveSync but connecting to MobileMe using ActiveSync is not possible, which is what I was getting at.
AFAIK, Snow Leopard will not include ActiveSync but rather a customized solution using RPC over HTTP(s) just like Outlook can for Windows. This is different than ActiveSync
No device is ever in SLEEP MODE.
Then you don't understand what SLEEP MODE is. Read the post from nagromme
At the risk of beating this topic to death, I have to follow up on my post from yesterday with all of these NEW features requiring an Intel machine.
What Apple is saying here is that if I have workers with G4 laptops, G5 towers or iMacs, and ANY kind of iPhone . . . I can't push my data to them unless I invest in an Intel based server so that I can install Snow Leopard server. What does this "push technology" have to do with the damn server processor?
Or you can buy Kerio Mail Server today and get excellent ActiveSync and CalDAV support -- better than Leopard Server IMO. Email, calendar items and contacts push out to iPhones without any trouble at all.
The server runs just great on PowerPC Macs and under Tiger.
So called "push" notification has always come across as a bit of fiction to me. If my device is sleeping, there is no magical way a remote server can wake my device and force a message upon it. Somewhere underneath the hood, the device is waking up, connecting to the server and accepting messages. The rest is just media hype.
On a phone the device will wake up the baseband portion to do some kind of ping notification to the central server over a control channel. This channel is also used for text sending and receiving. And in Blackberries, for sending push messages. I presume that unless Apple do the same, then yes, it's not push because most phones try not to wake the main CPU up unless something has occurred.
With the full networking ping, Apple would need to wake up the main CPU and systems, make a network connection to their servers (this takes a bit of time of course), send the required ping messages, and get the responses. This isn't push by any definition, and it also uses up a lot more battery power.
More than likely Apple is going to integrate into the control channel a small message that encodes the application name and a quotient and maybe a tiny message. Then if this occurs the baseband can wake up the main part of the phone to do the bigger data gathering or just handle the control channel message.
No, you can't stream Pandora with the latter. I hope that if the phone is awake, then more adventurous push updates and background apps will eventually be allowed.
So who gets to define "sleep"? A sleeping computer can still receive key and click signals, USB connections, ethernet wake signals, IR remote signals, Bluetooth signals, etc.
I don't believe that's true. I have NEVER seen the update badge pushed to my iPhone (and I do have Push enabled--Yahoo uses it). The only time I ever see a number on that icon is if I launch the App Store. (I don't have to go to Updates, just launching into any part of the store is fine). Then, when I exit, any updates I haven't downloaded get counted in a badge.
But if I never launch the App Store, I never see any update badge. That's not push.
I agree. I never see the the badge update until I go into the app store to check myself. Or sometimes when I sync to iTunes it will show up. That is not push at all. And in this article when it references the Push notification of RIM and Microsoft lets not even go there yet please. First of all Push should have been out 2 years ago when the iPhone came out. The phone is getting old and it is too slow to do things as is. Push notification is far too late for the iPhone now. I am ready to toss my 3G Lag iPhone and get something new that can update freely without lag. AKA the Palm Pre. Something that can truly multi task. And before anybody says the iPhone will out perform any phone at all... How come it lags when I text message. How come it lags in google maps? How come it lags switching from contacts to recents within the phone app. This phone is too slow Push notifications now will only make it work. Please don't pretend this is a business phone. No Business has time to deal with this slow in affective micro computing these days. Maybe the Windows mobile phone isn't pretty to look and and maybe it doesn't have fun games. It gets the job done.... If you guys want to see a noticable difference in quality and crap compare the iPhone to the Black Berry bold.... the bold is FAST. Lag free. You can email, copy/paste and text as well as push notifications all without any lag.
I agree. I never see the the badge update until I go into the app store to check myself. Or sometimes when I sync to iTunes it will show up. That is not push at all. And in this article when it references the Push notification of RIM and Microsoft lets not even go there yet please. First of all Push should have been out 2 years ago when the iPhone came out. The phone is getting old and it is too slow to do things as is. Push notification is far too late for the iPhone now. I am ready to toss my 3G Lag iPhone and get something new that can update freely without lag. AKA the Palm Pre. Something that can truly multi task. And before anybody says the iPhone will out perform any phone at all... How come it lags when I text message. How come it lags in google maps? How come it lags switching from contacts to recents within the phone app. This phone is too slow Push notifications now will only make it work. Please don't pretend this is a business phone. No Business has time to deal with this slow in affective micro computing these days. Maybe the Windows mobile phone isn't pretty to look and and maybe it doesn't have fun games. It gets the job done.... If you guys want to see a noticable difference in quality and crap compare the iPhone to the Black Berry bold.... the bold is FAST. Lag free. You can email, copy/paste and text as well as push notifications all without any lag.
In a nutshell... don't give me push my iPhone lags enough already.
Mobile email is king and Exchange and RIM have that down pretty good. Hopefully Apple can pull this off right the first time.
Yeah, for the love of god why doesn't Apple just license ActiveSync? For that matter, why don't they scrap MobileMe all together and just partner with Google. I use MobileMe now but do not foresee any reason to continue paying $100 a year as soon as Gmail offers push email.
IMHO, Google is MUCH better, in every aspect, at delivering web services than Apple and there is no evidence so suggest that would change in the future.
Maybe it has something to do with them being a web company.
I agree. I never see the the badge update until I go into the app store to check myself. Or sometimes when I sync to iTunes it will show up. That is not push at all. And in this article when it references the Push notification of RIM and Microsoft lets not even go there yet please. First of all Push should have been out 2 years ago when the iPhone came out. The phone is getting old and it is too slow to do things as is. Push notification is far too late for the iPhone now. I am ready to toss my 3G Lag iPhone and get something new that can update freely without lag. AKA the Palm Pre. Something that can truly multi task. And before anybody says the iPhone will out perform any phone at all... How come it lags when I text message. How come it lags in google maps? How come it lags switching from contacts to recents within the phone app. This phone is too slow Push notifications now will only make it work. Please don't pretend this is a business phone. No Business has time to deal with this slow in affective micro computing these days. Maybe the Windows mobile phone isn't pretty to look and and maybe it doesn't have fun games. It gets the job done.... If you guys want to see a noticable difference in quality and crap compare the iPhone to the Black Berry bold.... the bold is FAST. Lag free. You can email, copy/paste and text as well as push notifications all without any lag.
Windows Mobile is laggy as hell.
That's my whole point. The phone is never really sleeping.
It's not quite true. While the *whole* device might not be sleeping, wake-on-interrupt type hardware systems allow hardware designers to make a device that is sleeping except for very specific portions of the circuit, while the rest of the circuit / device is in sleep mode. The device that's "listening" basically pokes the rest of the system awake only if it's needed. A polling system would not allow as much of the device to sleep.
Mac OS 10.5.6 enabled push from the cloud to the OS X desktop.
MobileMe for Windows 1.3 enables push from the cloud to Windows.
There is no need to wait for Snow Leopard to get end-to-end push for MobileMe mail, contacts, calendars, and bookmarks.
To enable push, go to MobileMe system preferences and make sure the popup shows "Synchronize with MobileMe automatically"
It must at telecommunication level (GSM, 3G and more) , since the IP layer must be dormant when the phone is sleeping.
The comparison with the IM protocols in the article is not that good, because the the IM client has an active connection with the server, which is used for the push.
I'd just like to point out that this description of how email is currently working on the iPhone above is really overly "rosy" in that it makes it seem like it all works fine when clearly it doesn't.
...
For instance if the iPhone is turned off on your desktop and your local mail client is open on the desktop computer, the iPhone will have acquired the new email notifications as your mail is dealt with on the desktop computer during the day, but only by turning on the iPhone and starting the mobile mail client will it actually update your mail or fetch mail that hasn't been read. It also does not sync email in folders until you actually access that folder, it just focusses on the inbox so as to make it seem like your mail is all being synced. Worse, depending on your settings one often ends up with multiple copies of various inboxes outboxes etc. on your laptop, your desktop, your iPhone and your web client as well as copies of the copies. There is no way to get rid of them save manual deletion or manual resetting of your clients and mail settings.
If you TURN THE PHONE OFF there is no way it will get updates. May be you mean turning the display off? Do you have your push settings set properly on the computer and on the phone? Take a look at the advanced setting in the Fetch New Data on your phone.
As far as my sync experience is considered, I find the article pretty accurate. I have 2 IMAP and 1 exchange account on the phone and have no problem with the folder contents and marking the messages as read. If I open a mail application on my computer and read the new mail from the phone, I can see the mail updating the read status within seconds.
The folders, other than the inbox, are not constantly updated for purpose. This is a feature, not a bug. Most people rarely need to browse Sent Items, let alone deleted items. I would prefer to save battery life and 3G data transfer and not have these folders always synchronized.
Could somebody tell which protocol is used to implement the push technology?
It must at telecommunication level (GSM, 3G and more) , since the IP layer must be dormant when the phone is sleeping.
The comparison with the IM protocols in the article is not that good, because the the IM client has an active connection with the server, which is used for the push.
The iPhone doesn't sleep. The OS is always running. When there's nothing in the main event loop to run, the CPU goes off for a few milliseconds at a time.
I haven't instrumented an iPhone to measure, but with most similar systems: The baseband informs the main CPU whenever the cellular network sends it data. "Data" can be an incoming phone call, an incoming SMS, *or* an incoming IP packet.
In other words: incoming IP packets go straight to the OS, regardless of whether the system is fully operational, display off, or even asleep. You don't need to send continual packets to keep a link open. Once of my WinCE toys would actually fully wake up from sleep if you sent data over a TCP link.
TCP or UDP would be fine protocols to use for a push system with an architecture like the iPhone's. There wouldn't be additional overhead in terms of power usage.
That's my whole point. The phone is never really sleeping. It's still polling for messages. Messages still get queued. Now, you can correctly argue that this protocol is much lighter-weight and uses less radio time and power than setting up an IP connection and connecting to a mail server, but there's no magic "push" service that's saving battery by pushing out updates "immediately and only when necessary".
No messages are queued with push. As soon as they hit your inbox they're pushed to your device (unless your device is physically turned off, then yes, they'd be queued). If there are no messages then nothing is pushed. In a pull method, you need to schedule your phone to check in intervals. If there are messages they will get queued until your phone wakes up and checks. If there are no messages then your phone STILL wakes up and checks. This is where the battery savings come in. When your device is checking for messages even when there are none.
I understand what PMJoe is talking about, and it always confused me as well. People keep talking about the client device not having to poll the server to get a new message, as it simply gets "pushed" to the phone. Well how the hell can the server "push" email notifications (or any other data)to the phone if the phone's TCP/IP data connection is not active??
The only way I can imagine this happening would be if AT&T (or whoever) itself had equipment that sent notifications through the minimal "heartbeat" signal that lets your phone and the cell tower communicate.. Is that what the Blackberry Server does? If so, then the cell carrier has to install special blackberry push equipment right?
Also, How does ActiveSync compare to this? If the Push email on ActiveSync/MobileMe doesn't use the special cell->tower signal, then it has to be using standard TCP/IP connections, and how is that any different than polling??
Can someone with a technical understanding of this please comment!
I understand what PMJoe is talking about, and it always confused me as well. People keep talking about the client device not having to poll the server to get a new message, as it simply gets "pushed" to the phone. Well how the hell can the server "push" email notifications (or any other data)to the phone if the phone's TCP/IP data connection is not active??
Ahh, well, what do you mean by "active"?
Inside an operating system, it costs nothing more than a tiny bit of memory to have an "open" TCP link. The CPU doesn't have to do anything until a packet actually comes in. It's really just a pathway, knowing which app is supposed to get the packet. If the app is written properly, it will use *zero* CPU until something happens.
That's all well and good, but the packet needs to get to the CPU somehow. That means you need to have the radio on, and in the right state.
The radio is already on, and already informing the cellular system where it is.
When you are sending IP packets to a cellphone, you send them to an IP address like any other. You don't do any magic to tell the cellular system where to send them.
So:
You start out with a live GSM network link. Your baseband is up and running, registered on the AT&T network. But you can't do data. The iPhone OS tells the baseband, "Please get me an IP address."
Baseband talks to the GSM network, gets an IP address, gives it to the iPhone OS.
Now IP packets can be passed over the link.
Once we are in this state, the cost to *remain* in this state is zero. AT&T knows where the phone is. iPhone knows its IP address. AT&T IP network knows that this particular IP address goes to this particular cell tower which then sends it to your phone.
In the case of the iPhone, which never actually *sleeps*, but rather shuts off the bits it doesn't need, it can get a new IP packet from the baseband whenever one comes in. Other phones that do sleep can get woken up whenever the baseband has a message.
iPhone logs in via IP to the push system, proves that it's my iPhone. Then it just sits there. Push system knows the IP address to send my messages to. No further traffic is needed at the iPhone OS layer.
The only way I can imagine this happening would be if AT&T (or whoever) itself had equipment that sent notifications through the minimal "heartbeat" signal that lets your phone and the cell tower communicate.. Is that what the Blackberry Server does? If so, then the cell carrier has to install special blackberry push equipment right?
I don't know much about the implementation of Blackberry. They may also do different things with different models. I suspect that they send SMS or SMS-like messages. The carrier can do that quite easily if you're a big customer. It also ensures that you need a special data plan. The iPhone can do push with Yahoo, MobileMe and ActiveSync without the carrier being involved.
Also, How does ActiveSync compare to this? If the Push email on ActiveSync/MobileMe doesn't use the special cell->tower signal, then it has to be using standard TCP/IP connections, and how is that any different than polling??
Can someone with a technical understanding of this please comment!
I'm pretty sure that ActiveSync is a pure IP based system. I've never seen any carrier-specific requirements for ActiveSync, There's no single, unified open standard for sending SMS messages to a carrier. Without carrier-specific agreements and integration into their system, you're gonna be IP-only.
I hope this makes sense. My personal background is primarily in the IP domain. I've worked with a lot of cellphone systems, but I've never actually built a GSM radio, or directly integrated my stuff with a carrier. If somebody here does know about the overhead of keeping a PDP context activated on a UMTS network, and there's more to it than I am aware of, please correct me!