Interworking between Ad hoc Network

and Supporting Network

INFOTECH Seminar Advanced Communication Services

SS 2003

July 11, 2003Napat Nantavechsanti

Mentor : Dr.Stephan Rupp

1 : Wireless Networks 2 : Mobile Ad hoc Network: Basic concept 3 : Multihop Cellular Network 4 : Hierachical Cellular Multihop Network (HCMN) 5 : Conclusion

Agenda

Questions

Why do we need many different types of networks? Why don‘t we integrate them together and make use of this integrated system?

How can Ad Hoc relaying concepts improve the efficiency of the existing Cellular Networks?

WLAN : Based on ethernet backbone

Uses radio, infrared and microwave to transmit data without cable

Consists of nodes and access points

Provides good mobility but small coverage area

GSM : Single-hop cellular based on infrastructure architecture

Third-Generation Mobile Systems

Same concept as GSM but provides higher data rate, high speed access and support broadband services

Optimized for data transmission

Questions

Why do we need many different types of networks? Why don‘t we integrate them together and make use of this integrated system?

How can ad hoc relaying concepts improve the efficiency of the existing cellular networks?

Mobile Ad hoc Network (MANET)

Infrastructureless architecture Nodes are free to move then network’s structure is

changed dynamically because of members’ mobility The responsibility of direct communication determination

is determined by each node (self organizing and adaptive)

Multihop wireless network

Mobile Ad hoc Network (cont.)

Combination of the features of SCN and ad hoc cellular network

Feasible architecture for WLANs Mobile stations relay packets by relaying traffic from

congested cells to neighbor cell which have free bandwidth

3 systems using multihop concept:– iCAR (Integrated of Cellular and Ad hoc Relaying)– A-GSM (Ad hoc GSM)– HCMN (Hierarchical Cellular Multihop Network)

Multihop Cellular Network (MCN)

Basic Idea of iCAR

ARS (Ad-hoc Relaying Stations) is placed at necessary location to be used to relay signals between MH and BS

Each ARS and MH must have two interfaces;

– C interface for communicating with the BTS

– R interface for communicating with another ARS

ARSMH

MH X moving into congested Cell B is relayed to Cell A

Example of relaying

A B A Bx

x

(a) (b)

ARSMobile Host

Ad hoc GSM (A-GSM)

Extends the standard GSM radio interface with the capability to support relaying

Make use of the existing GSM architecture with minimal changes to support rapidly deployable network requirements

A-GSM network entities– Base station subsystems– Mobile switching centers– Network databases: HLR,

VLR, AC and EIR– Internetworking units– Integrated dual mode

terminal

Ad hoc GSM (cont.)

Hierarchical Cellular Multihop Network (HCMN)

Integration of different types of wireless networks, organized in layered structure

HCMN here will be considered as the integration of WLAN and cellular network

Hierarchical Cellular Multihop Network (cont.)

AP: Access PointMHN: Mobile Capable NodeMN: Mobile Node

Hierarchical Cellular Multihop Network with Fixed MHNs

Fixed MHN or so called „Extension Point (EP)“

– Situlates at the location where yield the highest benefit

– Used to extend the coverage of the AP

Hierarchical Cellular Multihop Network with Mobile MHN

Mobile MHN– Used when fixed

MHN cannot provide required throughput of the users.

– Routing algorithm becomes an important issue

Conclusion

Why do we need ad hoc cellular communication? – Increasing of subscribers including service needs– Insufficient resources in hot spot area– Useful when infrastructure not available, impractical, or expensive

Enhance the efficiency of the system in term of coverage area and balanced load of the system by using ad hoc concept

Some critical issues that should be considered– Security– Level of modification and implementation complexity and cost– Power control, etc.

Status: multihop communication is not yet deployed. IETF is working on the MANET standards.

...Thank you very much for your attention...

Questions