It has been interesting to see the varying replies to an open-ended question. One must ask one's self what is the purpose of this connection.
Is it for general / personal use where downloading is the criteria?
Is it for testing connection and speed response from given sources?
Are you hosting your server in tis environment?
Are you developing and uploading files continually to your server?
We all want the latest and greatest in terms of download. Hey time is money, however if your role is for testing and evaluating resources and the speed in which students experience, then you really need to consider a lowest common denominator. If you are serious about the work you are doing, then you may also need two options / alternatives. I run both a Dial-up and an ADSL here - one for testing and the other for general work.
Yes there is a cost involved, however it does ensure that the materials deployed are functional within the environment. In the end - if you have a slow delivery for the many that will connect using dialup, then you have a high probability that you will loose that student base. On the flip side - those that have low speed ADSL will be served well and those with a high-speed connection, will consider your program the best thing since sliced bread.
I would be interested to know how many Moodle sites have surveyed their student base to see what their connection is. Maybe this could be a part of the user registration page, as it is an indicator for the type of program delivery and the level of resources one will make available for the student base. This is one area where I would consider those in say a dial-up area, creating a course where the resources are supplied on CD/DVD (CD preferred as this is the lowest common denominator at the moment) but in time this will change.
In reality we should be targeting our connection speed predominantly used by our student base, that way we are continually reminded of their experiences.
For developers - well as fast as you can get and for those hosting their server at home - a synchronous connection 512Kbps min, otherwise your student base will soon get bored and move elsewhere.
Just two more bits worth -
Cj