WAN - Performance Futures
Increased bandwidth
- WDM (factor 4-16 today, going to 100)
- Competition to traditional carriers (e.g. Qwest)
- Intra continent
- US: More sites on I2, second I2 backbone (Abilene)
- Europe TEN-34 => TEN-155
- Inter continent more problematic
Differentiated services: policy tag packets and prioritize through Internet (premium class service)
Improved understanding: increased measurement of end-to-end performance & identifying bottlenecks
Notes:
Use of WDM moves the economics from transmission lines which are expensive
(labor intensive) to install, to electronics for which the cost/performance is falling
Charging is still some way off:
Issues: what to charge for: usage (as in phone system but cost of billing),
connection (flat pricing), where do premium services fit, who settles bill
(e.g. on transatlantic traffic is it user, A&R net etc.), inter-ISP settlements,
where is it measured (per hop, at edge), is it time sensitive, are there
incentives for traffic to be cooperative (e.g. TCP slow start), what is measured
(e.g. bytes/sec, loss, congestion pricing), how is it implemented.
If offer premium class then usage-sensitive pricing is
a necessity. Does not have to be onerous, even a small charge can have a
large effect. Burden of introducing charging would be heavy, especially if it
has to be accurate, reliable and auditable. Problem is that it makes something
which is already difficult to understand and manage even more complex.