110 likes | 193 Views
Anticipation: How can we predict Internet performance on satellite networks, and why do we want to do that?. Hans Kruse J. Warren McClure School of Communication Systems Management Ohio University kruse@ohio.edu. 5th SCGII. Introduction.
E N D
Anticipation:How can we predict Internet performance on satellite networks,and why do we want to do that? Hans KruseJ. Warren McClure School of Communication Systems ManagementOhio Universitykruse@ohio.edu 5th SCGII
Introduction • Satellite links produce long-delay control loops (in GEOs) or variable delay (in LEOs). • We cannot always predict how protocols and their implementations will react. • We need simple ways to study satellite networks under Internet-type loads.
Network Reference Points End User a Local Network b Regional Network c Global Internet Backbone
End User • Interface point (a) between one user (or very few users) and the network • Bandwidth must be usable by a single application • These issues have been studied and largely resolved for • Bulk data transfer • Web access
TCP Window Size 1 connection persistent
All other interfaces • At all other points traffic consists of a mix flows from different users and applications • Issues: • Utilization • Fairness • Appropriate Network Configuration • Mitigation Strategies
Example: ISP Egress Link Internal Net Dial-In Egress Users Traffic Trace
Traffic Statistics Outbound Egress Inbound Traffic Trace
An Equivalent Network Trafgen #1 Discard #1 Outbound Egress Inbound Discard #2 Trafgen #2