Upload speed for mail server

Generally speaking what sort of upload speed would a company with around 50 users need to run their own in house mail server? Serving a remote office and maybe 6 home workers. Just average day to day office stuff with attachments upto 10 meg from time to time.

10Meg time to time, if that means just once a day, and maybe 500 incoming emails and 100 outgoing, then no reason an ADSL2+ line would not serve needs if using an external mail server.

If business wants to run in house mail server, then if the backup MX is off-site ADSL2+ might be ok still, but if not then you might want to look at specific business connections like Leased Line/Ethernet which have better availability and thus less likely to be glitches causing lost business.

Probably more like 2500 in and 1000 out per day. The 10 meg attachments maybe 4 per user per day.

Still fairly small, as would be around 100MB for 2500 emails.

It is less about the speed of the connection, but more the reliability and how you would cope if the connection did break.

So size wise ADSL2+ with uploads up to 1 Mbps would wise, just ensuring backups in place to handle if/when the line breaks. Or whether you should host the mail server in the business premises or elsewhere.

OK thanks. Reason I ask is I'm one of the remote users. Attachments now download at around 40 KB/s whereas they used to download at close to full speed, so around 400KB/s. Feels like a step backwards.

It depends then as well on what else is on that connection. The mail server is likely only one item - if there are other data transfers going on then that would slow the line. It could be that it is being used to do cloud backups and so using upstream to backup servers? You would need to know exactly what else is happening on that connection.

That I'm not sure about, I'd need to do some more digging. I do know they are about 1 mile away from a small exchange with no LLU or 21CN so I assume no ADSL2+ access. So probably just the standard office upload speed of what? 600K after overheads? I've lost track of what those products are capable of as haven't used myself for years.

There's definitely no leased line etc.

Personally I don't rate standard ADSL upstream as being capable of supporting a business connection if the business is locally hosting things like mail servers. We have major performance issues on ADSL with offices of just 10 people or even less where we aren't locally hosting - add in the server traffic and you are stretching the capabilities of such a low upstream.

But then how were you ever getting 400KB/s? Is this just a mix up with capital / lowercase B? If you are retrieving I would expect to to be in kilobytes per second in which case an office ADSL product would be 800Kbit/s (ish) which would be 100KBytes/s.

Is this just a mixing of bits and bytes. The 400Kb/s you used to get would translate to around 50KB/s - not far off what you are saying. Need to just check you are using the right units otherwise it could just be you are getting the same speed now as before. And if it was 400Kbit/s then they could be the upload on a standard ADSL as that is what normal ADSL (non-business upstream) would be.

In reply to a post by ian72:

But then how were you ever getting 400KB/s? Is this just a mix up with capital / lowercase B? If you are retrieving I would expect to to be in kilobytes per second in which case an office ADSL product would be 800Kbit/s (ish) which would be 100KBytes/s.

Previously we just used 1and1, so got close to full downstream speed from their servers. 4Mb/8=500KB less 20% overheads = 400KB/s.

So they have moved from a hosted mail solution to a local server? In which case the server has gone from probably a gigabit leased line connection to an ADSL connection with potentially 400Kbit/s upstream - so you would expect to see that change in download rates.

Personally I would not have hosted a mail server for a company of that many employees on an ADSL line.