BPOS Bandwidth Considerations

BPOS (AKA Microsoft Online Services) is a great product and we’re seeing some really great interest from customers-which is always nice! One thing that needs to be considered, researched and understood is what effect using cloud based services will have on your bandwidth, as things that previously didn’t go over the internet now will.

Luckily Microsoft have done a great job of ensuring that BPOS doesn’t have a particularly negative effect on your existing infrastructure.

Technet has a great page covering this so below is a breakdown of the bandwidth for the various components.

Exchange Online:

The estimates provided in this section are based on the following assumptions:

• The average message size is 50 kilobytes (KB).
• Every message delivered is read.
• Half of all incoming mail is deleted.
• OWA clients log on and log off two times per day.

This table shows the user activity estimates used in these calculations:

 This shows the network activity generated by those users:

Examples of the above:

100 Heavy Outlook users = Network bytes/sec = (100 heavy users × (5,200 KB/user ÷ day)) ÷ (8 hr/day × 3600 sec/hr) = 18.5 KB/sec

100 medium OWA users = Network bytes/sec = (100 medium users × (12,220 KB/user ÷ day)) ÷ (8 hr/day × 3600 sec/hr) = 42.4 KB/sec

Microsoft recommend basing calculations on a peak of twice the daily average thus giving you 37KB/Sec and 84.9KB/Sec respectively.

Sharepoint Online:

This is based on the following:

An average interaction (page load) transfers approximately 100 KB.

A typical user generates about 36 interactions (page loads) per hour.

About 10 percent of a company’s users will be active at the same time.

and that all users are in the same time zone.

For 1000 sharepoint users, the calculation would be:

Network bits per second = (100,000 bytes/load * 8 bits/byte * 36 loads/hr) / 3600 seconds/hr = 8000 bits per second

Estimating 10% of users to be active at any one time would give 800 x 8000 bits per second aka 800 kilobits per second. So again assuming a peak of twice the average, Sharepoint Online would require a 1.6 megabits per second network.

Sharepoint Online also requires a maximum latency of 250 milliseconds.

Office Live Meeting:

The Office Live Meeting Client has the following requirements: