email speed

[charlottesoper]

what factors affect the speed an email travels?

[rgoelmsft]

If I were to interpret your question very literally, "the speed that an email travels" is always constant and it is not affected by *any* factors. It is the speed at which electrons travel through a wire, which is close to the speed of light. But of course, that's not a very useful answer. What I suspect you actually meant to ask is, "What factors can affect the amount of time it takes for an email to get from the sender to the recipient?" The answer to that question is that there are a *lot* of factors. I'll name just a few:

* The size of the email. In other words, if you attach lots of large photos to the email, it will take longer to send.

* The bandwidth (capacity) of the network between the sender's computer and the sender's ISP (internet service provider). In other words, if the sender is using a dial-up modem to connect to his ISP, the email will take longer to send than if he is using a fiber-optic DSL broadband connection.

* The bandwidth (capacity) of the network between the recipient's computer and the recipient's ISP. Same thing ... if the recipient is using dial-up vs. a broadband connection, it will make a difference.

* The load on the sender's email server. If the sender's email server happens to be very busy (because suppose all of its users all decided to send emails at the same time), then it puts the incoming requests into a queue to be processed, and you may have to wait a while before it's able to get to yours.

* The load on the recipient's email server. Same thing ... if the recipient's email server happens to be very busy at a given moment, it will take longer for the email to be delivered.

* The physical distance between the sender's computer and the sender's email server, the sender's email server and the recipient's email server, the recipient's email server and the recipient's computer. But more importantly, it's the total number of hops on the internet that the email will have to make to get from the sender's computer to the recipient's computer, which is correlated to the physical distance between them.

* The general load on the internet at the time the email is sent. Internet traffic fluctuates, and sending the email during low traffic periods (nighttime) will probably cause it to arrive faster than during peak traffic periods.

* The frequency at which the recipient's email client is checking the server for any new mail. For example, some email programs may be configured to only check for new mail every five minutes, in which case the recipient may have to wait up to five minutes before he actually sees the email.

I hope this helps. I'm not an expert in email protocol, so others should definitely feel free to respond with a better answer. This is a creative idea for a science project, but I'm worried that it may be difficult to get reliable experimental results, because there are so many factors that are outside of your control.

--Rajeev

[mpphlipot]

Everything Rajeev said is right on the money. In a more general statement, you can pretty much draw analogies between US Postal Service and electronic mail. We all know there are countless elements that can affect how long it takes a postal package to get from person A to person B. Like how many intermediate stops it has to make along the way, what route it goes and how long it sits in a pile at each stop before it gets moved along. The very same thing applies to email. The various computers that handle the email as it travels along can be functioning smoothly and the the mail speeds along w/hardly any delay. They could be backed up and the email sits in a queue for seconds, minutes or even hours before it gets handled. Or a computer in the path could be completely out of commision and the email has to get buffered up until that that computer is brought back on line.

There are even analogies to a postal mail item getting lost or dropped off a truck someplace. A programming bug or electronic glitch could scramble the destination address of an email. The resulting email may get routed to the wrong address and probably get rejected or it might just get deleted because it isn't a valid email address anymore.

So if it can happen to regular mail, it can probably happen in a similar, analogous fashion to email, as well.
Mike

[Craig_Bridge]

One way to investigate some of these factors for a specific case is to look at the message headers that are typically not shown. These headers show the receipt and send time from each computer node in the forwarding chain the messages was routed through.