1 / 16

Wireless TCP Performance Issues

Wireless TCP Performance Issues. CPSC 441. Hard to distinguish losses here from losses here. Example #1. Wireless TCP Performance Problems. Low capacity, high error rate. Wired Internet. High capacity, low error rate. Wireless Access. Example #1 (Cont’d).

denton-santos
Download Presentation

Wireless TCP Performance 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. Wireless TCP Performance Issues CPSC 441 CPSC 441

  2. Hard to distinguish losses here from losses here Example #1 • Wireless TCP Performance Problems Low capacity, high error rate Wired Internet High capacity, low error rate Wireless Access CPSC 441

  3. Example #1 (Cont’d) • Solution: “wireless-aware TCP” (I-TCP, ProxyTCP, Snoop-TCP, split connections...) CPSC 441

  4. DATA DATA Loss of ACK = Loss of DATA ACK ACK Example #2 • Wireless TCP Fairness Problems D Wired Internet Wireless Bottleneck AP U CPSC 441

  5. Example #3 • Multi-hop “ad hoc” networking Kelly Carey CPSC 441

  6. Example #3 (Cont’d) • Multi-hop “ad hoc” networking Kelly Carey CPSC 441

  7. Example #3 (Cont’d) • Multi-hop “ad hoc” networking Kelly Carey CPSC 441

  8. Example #3 (Cont’d) • Multi-hop “ad hoc” networking Kelly Carey CPSC 441

  9. Example #3 (Cont’d) • Multi-hop “ad hoc” networking Kelly Carey CPSC 441

  10. Example #3 (Cont’d) • Multi-hop “ad hoc” networking Kelly Carey CPSC 441

  11. Example #3 (Cont’d) • Multi-hop “ad hoc” networking Kelly Carey CPSC 441

  12. Example #3 (Cont’d) • Multi-hop “ad hoc” networking Kelly Carey CPSC 441

  13. Example #3 (Cont’d) • Multi-hop “ad hoc” networking Kelly Carey CPSC 441

  14. Example #3 (Cont’d) • Multi-hop “ad hoc” networking Kelly Carey CPSC 441

  15. Example #3 (Cont’d) • Two interesting subproblems: • Dynamic ad hoc routing: node movement can disrupt the IP routing path at any time, disrupting TCP connection; yet another way to lose packets!!!; possible solution: Explicit Loss Notification (ELN)? Handoff? Route prediction? • TCP flow control: the bursty nature of TCP packet transmissions can create contention for the shared wireless channel among forwarding nodes; collisions between DATA and ACKs possible solution: rate-based flow control? Burst mode? Spatial reuse of channels? CPSC 441

  16. Summary of Wireless TCP • TCP is the “four wheel drive” of TP’s • Wireless is a newly emerging technology with rapidly growing deployment popularity • “TCP” and “Wireless” don’t fit together all that well • Making TCP smarter about wireless helps! CPSC 441

More Related