1 / 8

Interdomain and end-to-end QoS issues

This document discusses key challenges in interdomain and end-to-end Quality of Service (QoS) as outlined by Henning Schulzrinne at the NSF QoS workshop in April 2002. Critical issues such as scalability, the importance of diversity in signaling, and the need for robust AAA (Authentication, Authorization, Accounting) mechanisms are explored. The document highlights the need for effective signaling protocols, the complexity of multicast, and the difficulties of cross-domain authentication. Additionally, business model inadequacies and real-world examples of resource reservation in VoIP are reviewed for practical understanding.

mattox
Télécharger la présentation

Interdomain and end-to-end QoS issues

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Interdomain and end-to-end QoS issues Henning Schulzrinne Columbia University NSF QoS workshop – April 2002

  2. Issues • What's hard to scale (and what's not) • diversity is good • AAA needs a tow truck • business models don't work

  3. What's hard to scale (and not) • Signaling does not have be hard: • one message, on a reliable peering channel or IP router alert option • NSIS effort in the IETF? • YESSIR: RTCP-based signaling • 700 MHz Celeron processor • 10,000 flow setups/second  300,000 softstate flows • If scaling matters, sink-tree based reservation (BGRP)

  4. Diversity is good • Unlike routing, no need for single signaling protocol: • multicast is much harder • dumb end devices • edge "pop-up"  only show up in edge nodes

  5. AAA • Signaling can easily be done in ASIC (no harder than IP), but • need cryptographic verification of request • need interface to Authentication, Authorization, Accounting (AAA) • cross-domain authentication  hard, but 3G networks will do it anyway • easier if both sides ask their own access router • see also: iPass for dial-up, OSP (open settlement protocol)

  6. AAA example reserves for both directions Internet AR1 AR2 source destination signs request Cell phone model: both sides pay

  7. Reservation scaling • Example: every long-distance call in the US uses VoIP with per-flow resource reservation • 2000: 567.4 billion minutes @ 10 minutes each  1,800 calls/second • single mySQL server can sustain 500—2,000 queries+updates/second

  8. Business models don't work • Most of the time, "tin" service is no worse than "platinum" service • can't impress others with platinum AmEx card • no frequent flyer bonuses •  everybody switches only when the network is in bad shape

More Related