Push mechanism of Exchange Activesync - email

I've a question regarding the over all design of push email and specifically the approach taken by Exchange ActiveSync.
As I understand there are two basic ways to get push email with the following architecture
Device <---> Push Email Server <---> Actual Email server
Keep a constant socket connection between Push email server and device. Push email server will inform device over the connection.
Related technology - IMAP IDLE
No sms gateway required
The Push email server will send a message (wap push, sms etc) to ask device to download new email.
Related technology- OMA-ENM
Needs a SMS gateway at Push email server
Considering this, what type of push email service does Exchange Activesync actually offer?
(AFAIK, white label push solution from Emoze/Synchronica uses the 1st approach - constant connection over something like IMAP-IDLE).

Exchange ActiveSync uses Direct Push. The client (phone, whatever) syncs with the Exchange server and then makes a very long-running HTTP POST request (called a "PING", but it's not an ICMP ping or anything like that). When the client issues the request they specify how long it should run for (typically it's on the order of many minutes).
That HTTP POST request will sit there idle on the Exchange server's side until either a change occurs in the mailbox or the time period requested by the client had simply passed with nothing of interest happening.
In the case of the former - where something changed in the mailbox - the return value of the POST call indicates to the client that it needs to re-sync with the mailbox to pull down the latest changes.
In the case of the latter - where nothing changed at all - the return value specifies this and the client simply re-sends another long-running PING to the server, repeating the whole process again.
So it's your #1, really. For more information, this Microsoft link goes into more detail.

I think Exchange ActiveSync offers something similar to IMAP-IDLE, see below...
http://technet.microsoft.com/en-us/library/aa997252.aspx
If you've come to a different conclusion please post. Thanks!

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I am creating an email spammer, for an outstanding cause [closed]

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In Cuba, web access is extremely censored, so I created a tool that allows more than 50,000 people to browse the Internet through email. Cubans send me an email with an URL in the subject line, and I email them back with the response. Read more at https://apretaste.com.
It was working like a charm, till the communist government of Cuba started blocking my emails. My solution was rotation.
I started with Amazon SES, and I was changing the domain each time it was blocked, but Amazon adds a header to all emails, and once they blocked the header no email from SES was able to reach Cuba any more. The same happened with Mailgun and others, they all add headers.
Currently I am creating Gmail accounts and sending via SMTP, but Google blocks me for no reason and only allows to send 100 emails a day per account. Also I can only create few emails using the same IP address/phone, so I was forced to use anonymous proxies and fake Chinese phones. Now I am fighting a war on two fronts.
An email can be blocked by three parameters: IP address, domain, and email address.
It will be terrific if I can set up my own Postfix server at a VPS that auto-rotates the IP address. Even better if I can simulate "gmail.com", to avoid purchasing a new domain every day.
All the intents to create what I call "the ultimate sender" just either reach the spam folder or add unwanted headers making it too easy to block. I feel exhausted. I hit a knowledge barrier here.
I know I am crossing to the dark side, but this is for a very good cause. Thousands count on this service as their only source of unbiased news, social network and to feel part of the 21st century.
Can you please help me implementing "the ultimate sender", or pointing to another solution that I may be missing?
I have a few suggestions for you.
The first one relies on The Onion Router also known as Tor.
Since you are crossing to the dark side, why not also take a look into the darknet?
Take a look at this list of Tor email providers. If you have your own email server that can be accessed through Tor, it becomes much harder for anybody to stop people from using this service. After all, Tor was developed to offer people uncensored access to the web.
You can read about Tor in detail here, it uses Onion Routing and this is how you would set up your server to use Tor.
Here is an example how you could use it:
The steps that involve the setup, receiving an URL request and sending back the reply are as follows:
Set up an email server.
Configure your email server to use Tor.
Publish the public service name. (e.g. "duskgytldkxiuqc6.onion")
Deploy a client that takes the service name and a URL, and let it send an email with a request to your server.
The client now waits for a reply.
You send a reply and the client receives it.
You can change your service name on a regular basis, but you need to make it accessible to those who will use this service.
Having an own email server means being able to control the email header.
Here is one example how you could make use of it:
Configure your email server so that it receives and recognizes
emails which contain the requested URLs.
Before you send a reply modify the email header so that it shows a random IP address and a random sender email address including a random domain name.
Send your reply.
Sending an email that way means that you cannot be replied back to. But since your reply already contains the requested information there is no need to.
I hope this helps.
Crowd source it.
Find a way that volunteers can send some emails for you. This is the only long term approach that I can think of. A simple web interface with mail to links would be be enough to get started although there are other potential problems with this approach too.
Because you are talking about low numbers of users, you could also use crowdsourcing to create the single email address per person approach. They can create an account on a specific set of email providers and give you the credentials. This would allow the single email per user approach or could be used to rotate through a large set of email accounts to send emails.
The simplest solution is perhaps to set up a local SMTP server on your own computer. You don't even need a server per se.
https://sourceforge.net/projects/winsmtpserver/
There are many other such applications. They are usually used to test SMTP functions during local development, but there is nothing against actually sending spam through them.
I know this would be quite a large task, but how about pairing the users with one or just a few emails so they always receive an email from that email.
I'd assume people wouldn't have more than 100 queries per day, if so they could start receiving them from a backup email
I'd imagine it would look less suspicious for them to appear to be in constant contact with one unique email rather than 50,000 being in contact with one
I know this would be a huge undertaking, but I feel like it solves your issue.
Since the users are willing to receive emails form you then your shouldn't be blocked.
When you mentioned you are getting block does it mean your mail is going in spam or is getting lost in between sending and receiving or it is getting bounced back??
My suggestion would be to setup your own mail server and follow as below:
-Get approx 25 or more ip to rotate. (IP is the most imp part which is tracked and is accountable for the reputation of your mail server)
Don't start sending emails in bulk from the word go it is better to gradullay increase the email volume so that mail server reputation nicely built
keep changing the format of the email often
encourage user to add yourself to there contact list
your best part is user are willing to receive emails from you and you would reply to revived email is the USP of yours but still i will recommend you to register for FBL so that you would know which user is reporting you as spam and you can remove him from your list and never send him email again.
using best practice to send emails like dkim, SPF, dmarc are also vital.
Hope my answer was of some help to you. If you need step by step guide to step up mail server let me know.
My friend, do you remember what made Hillary Clinton lose the last elections to Trump?
It was the "mail" affair. And what was it? People discovered she shared confidential information through a non-official, non-governmental email account (i.e., she used some Gmail, Yahoo or another of a kind). Until here, nothing new with direct relation to your matters. But there is an small particularity on this history, and this can put, maybe not a solution, but maybe a light on a new path you could follow: Clinton actually never sent those emails; the email account she used had the password shared and the communication between people (Clinton-someone) occurred only using the drafts of the account.
How? One side logs in and accesses the drafts folder. There he/she reads the last message and edits it, cutting and writing new data - then save the draft message. On the next turn, the other side of the communication line logs in and do the same. And so forth, so never really sending those messages, but instead just updating the drafts (this "Hillary" method does schooled people... Dilma Rousseff, impeached ex-president of Brazil, actually did this method down there in Brazil too).
So, maybe if you could establish a pact with your user that he/she doesn't delete the account's password, you could pass those information by this method - without "really" exchanging emails. Maybe a "parent" email account (some that could reset a lost password) could be useful too.
Alternative: aren't you able to contract a regular HTTP webserver? You could rely on FTP to publish data to your user, he/she asks for it and you publish a page with that content.
Salvi, have you tried something with Telnet? OK, we are talking here about a text-only environment, but if nothing more would rest in the future, this could be better than nothing. Maybe you could implement a podcast-like, or push-like service based on it. Look what people do with it with references to your walk on the dark side...
If in Windows, open your command prompt.
Type telnet and press Enter.
Type "o" without quotes and press Enter.
Type "towel.blinkenlights.nl" without the quotes and press Enter.

How to track failover email notification?

I am sending email from application. My problem is when your type email address means format is correct but it may be not available anywhere.so when I am trying send such email address using SMTP through application, so how to track fail-over notification if intended recipient not found.
please suggest any approach.
There is no standard way of doing this. You might be able to make it work in some cases by parsing incoming email looking for delivery failure notices but it'll be a lot of work to keep that parsing code up to date. So at best you'll only get some of the notices. If you get a notice at all. The recipient's SMTP server may not send you anything, or the notice might get lost on it's way back to you.
The only way you are reliably get this sort of information is to host the SMTP server yourself, and deliver directly to the recipients SMTP server. In that case the SMTP server knows the status of the email's delivery and could report that to your email client via some non-standard back channel.
Note: Hosting your own SMTP server is non-trivial. And you will probably need to be on a fixed IP otherwise external SMTP servers will treat your email as spam. In case you're thinking of running one over a home connection or something.

Email Server to only handle inbound messaging and routing

Was hoping for some ideas as to a service to which I can set up an inbound-only email system. In other words, I will have multiple users on the system, each can receive their own email... but at the moment... at this time, I am not focused on the ability to send or reply to messages, only receive them and send to the appropriate user. I looked into Postmark... They seem to have some great functionality.
CloudMailin Is another alternative. However there are effectively three options for setting up something like this.
Use an existing, traditional, email server and poll for the emails
Setup your own email server and create a script to run when you receive an email
Use a third party solution, as you've already mentioned.
I went through for of these for Rails a little while back here, but all the information is still relevant.

Can an IMAP client automatically filter messages that an IMAP server receives?

Let's suppose I have created an IMAP client and I want to create a filter that, say, deletes messages that have certain characteristics.
I can make this a startup task that happens whenever the client is opened, but the problen is that a user might view the inbox in a different client and the filter won't get rid of the unwanted messages before the inbox is viewed.
Is there some way to tell the server to call my service every time it receives a message so the unwanted messages can go away once the server receives them instead of once a client is opened? Is this even possible with IMAP? If not, is there a different well supported e-mail technology that allows this sort of interaction?
You can do server-side email filtering with the Sieve Email Filtering Language and the ManageSieve Protocol. There is good support in open-source software. However, I am only aware of a few major email providers, that support it. If it is supported, it is usually accessible on the IMAP host and with the IMAP account credentials, i.e. you can test it by connecting to TCP port 2000 and 4190.
See the following three links for more information:
http://en.wikipedia.org/wiki/Sieve_%28mail_filtering_language%29
https://www.rfc-editor.org/rfc/rfc5228 (Sieve: An Email Filtering Language)
https://www.rfc-editor.org/rfc/rfc5804 (ManageSieve Protocol)
Sieve also supports a few notifications types. If the filtering language is not powerful enough to for your purposes, you can send notifications for all incoming emails, wake up the IMAP client, and let the client to the filtering.

Handling undelivered emails using Zend Mail

I'm sending newsletter using Zend Mail. I have used setReturnPath() to put all undelivered mail notifications in one place.
And what now?
How to get the list of addresses which were unreachable?
How do I read and parse the returned notifications?
How to know whether the mail returned because of non existing email or just quota exceeded?
Which headers do I need to send and check?
Related:
Variable Envelope Return Pathwiki
Handling undelivered emails in web appso
This class may be helpful. Can determine whether the mail is a bounce and return a response code with description:
http://www.phpclasses.org/package/2691-PHP-Parse-bounced-e-mail-message-reports.html
Short Answer:
you can't do that in a simple way and not in your app.
Long Answer:
You should handle that in asynchronous way and outside your php app (at least in part). First of all you must setup the return address to something like sender+recipient=recipientdomain.com#senderdomain.com as in the TimB answer. At this point all the notification sent by receiving smtp server will go to that address.
Then you need to setup the smtp daemon at senderdomain.com mail exchanger to handle that kind of bounce messages and process them in some sort of pipe.
With a pipe you can forward the returned message to an external program which parse the message and extract the needed informations (i.e. the reason why the delivery is failed)
At that point in your program (which can be a cli script in your application) you can mark the address as failing and optionally can record why.
This is a pretty difficult task, which can't be handled in a simple application. Usually I use a dedicated software for large mailing list handling such as sympa which takes care of this task for you.
Otherwise you can use an external delivery service such as Sendgrid which will do the dirty job for you and report the failing addresses with a simple API. As a bonus with this solution, they are in the whitelists for all the major providers, so your email won't be marked as spam as far as you respect some simple rules (i.e. removing bouncing addresses and use an opt-in policy for your newsletter)
Well, the second link and especially the answer by TimB explains very well the procedure.
What may not be clear is that the return path is nothing other than a regular email account, i.e. you will get the email to that address. Zend_Mail is not waiting for a response and hence there is no list of addresses.