The Things You Should Consider When Looking at Different Internet Connections
A large office, with lots of users in the building, may be sharing a contended service with other offices so whilst it is OK for domestic environments to share in this way (because there are so few in each house using the internet) businesses, by their very nature, have far more people connected to the internet and so more people all vying for the same connection capacity. There are business subscriber line services which have far lower contention ratios, but you pay for what you get.
Domestic subscriber line packages are typically 50:1 contention (50 subscribers bundled together to share the capacity at the exchange) whereas business packages tend to be 20:1, 10:1 and 5:1, each with varying costs. The lower the contention ratio, the higher the package cost.
Leased lines, internet connections that are symmetric and uncontended, are far more suited to SME internet needs and provide a robust and reliable speeds because all the bandwidth is available all the time, not shared with others, causing issues at peak times AND they cost less than you may think!