One of the common questions among new users is the seeming delay in receiving email on the BlackBerry handheld. Users see that the email hits their web service, and is not instantaneously on their device.
Unlike other PDAs, the BlackBerry device does not log into your email account for you, and check for new messages. This pull type email is best related to having a Post Office box. It requires physical action on your part to go and check your mail. You have to get up, drive in your car to the PO Box location, open it up, check for new mail, get back in your car, and drive home. All this time you are expending time and energy. What happens if you are unable to check the box due to the store/post office being closed? You have to wait until the next chance you get, and then check. As you can see this is not a very time/energy efficient way of doing things.
On the other hand, if you had someone to bring your mail to you, a Postal worker wouldn’t that be a better alternative? All you have to do is sit at home and when the mail arrives you have it. No need to do anything, no need to go anywhere else. This is how the BlackBerry architecture works.
When you integrate your email accounts via the device or the web portal, RIM’s servers store that email address and password. They use a static IP connection to connect to your existing mail box and check for new mail. For the most part, the BIS does not stay connected continuously to your email account.
Sample Setup:
1.
Log into your carrier specific account. A list is found here: Global BIS list
A. If you are an existing user, enter your username and password
B. If you have not set up your account before, click “Create new account”
i. Agree to the terms and conditions.
ii. Enter the PIN of the BlackBerry device
iii. Enter either the IMEI or the ESN
a. If you are using a hybrid CDMA/GSM device, enter the identifier
that would be used on your home network. (i.e., Sprint 8830 use
the ESN)
iv. Enter a username and choose a password. (retype for accuracy)
2.
To add an email account enter your email address (whatever@gmail.com) and the password you use to log into that account and click next.
a. Keep in mind this is not the username that you would use to log in, it is the entire email address.
3.
Provided you have the credentials correct, and that you do not require any advanced setup for that account (not usually required) you will get a message indicating that your account has been successfully added.
4.
You may also add your carrier provided blackberry email address through this screen. Click “Create address”
a. Enter your username and click next. If the username is available you will receive the same successfully added message
That is it, you are done. Obviously you can continue to add email addresses, to a total of 10 integrates plus the one free BlackBerry email address.
That’s great, now how does the device actually get the mail?
When an email is sent to you, from another user it traverses the internet until it gets to your email provider where it is stored in your mailbox and waits. The BlackBerry servers will periodically check that mailbox (provided you have added it to the device) for new messages.
The BIS itself will check for new messages every fifteen minutes by default. If it does find a new message, the message is compressed, and the first 2kb of data is then pushed to the device. For the next fifteen minutes, the BIS will check every three minutes for new mail. If no new mail is found within that second set of fifteen minutes, the server reverts to again checking once every fifteen minutes. As long as the server finds new mail within that time frame, it will continue to check every three minutes. This does not, however, apply to all email accounts. Gmail and Yahoo mail are two notable exceptions to this rule. The BIS remains constantly connected to these services, and will push new email automatically to the device, without the fifteen minute interval.
This is why users will see a variable delay when receiving mail. When thinking about the BIS, keep in mind that it can take up to fifteen minutes to get your email on some accounts. Instant solutions are out there, but if you just have to have that college email on your device from a school you attended many years ago (as the case is with me) you now will be able to anticipate the delay in receiving those emails from long lost buddies.
For a complete walk-through of the email setup visit
http://www.blackberry.com/select/bisdemo/index.htm
Originally written by me at
BBNews 
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