Are the dates moving, or they are upgrading and users are growing their data use to consume available bandwidth even after upgrades.
This has happened with BT Wholesale upgrades in the past, when incremental increases in capacity are not enough.
Probably both.
VM wait until utilisation tops 90% before even starting to plan an upgrade. By then performance is severely impacted already and then the time from planning to relief been provided can be several months. During that time they are of course still signing up new customers and the upgrade may well only be a small incremental amount. It does seem from where I sit VM want and try to keep utilisation at around 90-100% and only act when thngs get extremely bad,
On my current high utilisation fault I am now on my 4th ticket, they just keep getting closed with no real reason.
To give you an idea how bad it is to wait until 90. 10% of a upstream pipe is only 1.8mbit/sec. 100mbit users can consume 60% all by themselves, 50mbit 30% and 30mbit about 17%. Jitter is likely noticeable on anything above about 40% utilisation.
Comcast a US cable provider consider 70% as high utilisation and thats on larger shared pipes as well.
Edited by Chrysalis (Wed 08-Feb-12 12:41:59)