1 Bayani Carbone, Miguel Naranjo, Uloaku Ojiaku, Zhi Qu, Zhichao Wu

2 Present situation Software available for single connection sharing Is it possible to do better on the 3G link? YES

3 What we want to do… Internet access similar to residential broadband using bandwidth aggregation.

4 Project scope Bandwidth aggregation No special configuration required on the client, the service provider’s network infrastructure or the Internet based server. Normal function should not be interrupted when a mobile device newly joins or leaves the setup. Study of the effect of mobility on the system’s operation. (e.g. on a moving train). Taking battery level of mobile device into account in the management of the system. Avoiding poor TCP performance in system due to wireless 3G link.

5 Out of Scope Multi-platform support Slave mobile devices acting as sub-managers to other slaves. System security issues (protecting system components against possible malicious attack). Maintaining fairness in shared TCP congested links. Performance optimization when mobile components of the system are in motion. Billing and charging.

6 Goals Simulate and implement: – detection of arrival and departure of routers (mobile devices) – Intelligent striping mechanism – Manager and proxy software Achieve higher throughput using multiple links. No modifications to the client, 3G network and Internet based server. Study effects of mobility on entire system. Take battery level into account in the system management. Highest Priority Lowest Priority

7 Benefits CategoryCashableNon-cashable Research ▪ Providing a working solution for aggregating bandwidth over 3G mobile networks. ▪ Characterisation of the performance of TCP over 3G. Business ▪ Resulting software could be sold to 3G mobile users to enable them enjoy this facility. ▪ Network operators, using this software, could offer this value-added functionality to customers as a loyalty incentive or as an additional paid service.

8 Constraints / Technical Challenges Need to modify the TCP/IP stack only in BAM routers and proxy  Use of Linux Availability of 3G/ enabled mobile devices  Use Linux boxes with and 3G USB interfaces Short time frame for project completion

9 Architecture

10 Architecture

11 Architecture

12 Discovery/ Monitoring protocol Detect arrivals/departures of BAM routers Collect information for striping mechanism

13 Want to transfer a file of size B Throughput link 1 Throughput link 2 Theoretical minimal transfer time 13 Striping Mechanism

14 B = s 1 + s 2 Want to choose s i to minimize: → When all the are equal Therefore,,is the optimal allocation of packets on link k. Striping Mechanism (contd.)

15 Uplink / Downlink processing Uplink with striping Packet 1 Packet 2 Ack 1 Ack 2

16 Uplink with striping Packet 1 Packet 2 Ack 1 Ack 2 Uplink / Downlink processing

17 Uplink with striping Packet 1 Packet 2 Ack 1 Ack 2 Uplink / Downlink processing

18 Downlink with striping Packet 1 Packet 2 Ack 1 Ack 2 Uplink / Downlink processing

19 Downlink with striping Packet 1 Packet 2 Ack 1 Ack 2 Uplink / Downlink processing

20 Downlink with striping Packet 1 Packet 2 Ack 1 Ack 2 Uplink / Downlink processing

21 Technologies Simulator : – NS-2 Modular router – Click Wireless technologies: – 3G (UMTS) – Programming Languages – C++ – OTCL – Click language

22 Methodology-XP XP in the practical part of development Copyright J. Donovan Wells

23 Iteration Iteration Planning Develop – Stand up meeting – Programming Create unit test Pair programming Unit test – Bug fixed / Run Acceptance test

24 How will we monitor progress? Use wiki for task backlog Measure number of past acceptance tests Monitor rate of work (velocity) Derive XmR charts for project control G. Collins, Agile Metrics 2007, slide 16, GZ07

25 Evaluation Metrics Throughput for file download / upload – Compared to single highest throughput link – Compared to idealized single aggregated link Throughput under mobility Battery level of routers

26 Proposed Phases Phase 1: Research Phase 2: - Research papers -Familiarize with NS-2 /Click Overall design Selection of protocols TCP over 3G experiments -Mobile devices *Discovery protocol *Manager protocol -Striping protocol *Slaves protocol - Proxy *Mgt protocol *Striping protocol Implementation (NS2/Click), Testing and Optimization Architecture Phase 4: -Experiments (Real life/ NS-2) *Compare to highest throughput link *Compare to aggregate link - Mobility - Battery consumption Performance Evaluation Phase 5: - Individual report - Overall report -Presentation Documentation Phase 3:

27 Timeline

28 Project Team  Documentations monitoring and control  Software (Ns-2 ) developer  Technical co- ordination / management  Software developer  NS-2/Click specialist  System design architect  Software developer  Click specialist  Project manager  Software (Ns-2) developer  Internal and external communications co-ordination.  Administrative Support  Software developer/ Click specialist  Logistics ZhichaoBayaniMiguelUloakuZhi

29 Team Communication Regular meetings (three times a week on average) Internet-based Wiki – Meeting summaries – Task assignment – Suggestions – Review of the different concepts, protocols, components – Risk / Issues identification and monitoring Instant messaging and

30 Risk management

31 Risk matrix Undesirable Serious Critical Negligible Serious UndesirableNegligible Undesirable Likelihood Impact High Low Medium

32 What has been done so far... Problem description Scope definition Research on relevant past papers Wiki setup NS-2/CLICK installation Architectural design drafts Preliminary protocols definitions

33 What to do next TCP over 3G (UMTS) experiment – Finalise architecture – Finalise protocol definition Begin implementation phase

34 Related Work MARS: Bandwidth aggregation for multi-homed mobile router device mTCP: Bandwidth aggregation over modified TCP GPRSWeb: improving TCP performance over GPRS (proxy functionalities) TCP performance over 3G