Heterogeneous Services And Architectures for
Next-Generation Wireless Networks
And
Integrating Heterogeneous Wireless
Technologies: A Cellular Aided Mobile Ad hoc
Network (CAMA)
Heterogeneous Services and Architecture
for Next-Generation Wireless Networks
Simone Frattasi, Rasmus L. Olsen, Frank H.P. Fitzek, Ramjee Prasad (Aalborg
University, Denmark)
Mauro De Sanctis – (University of Rome, “Tor Vergata”)
http://ctif.aau.dk/
Next Generation Networks (NGNs)
• 4G
– MAGIC – extension of 3G cellular (cellular
structure with over 100 mbit/s rates) = linear
4G vision (Japan)
– Seamless service across multitude of wireless
systems (non cellular) = concurrent 4G
version
• Focus on personalized heterogeneous services
Wireless Personal Area Network
• Person to Person (P2P) vs. Person to
Machine (P2M)
Services
• Resource Sharing
– Efficiently organize resource consuption (e.g.
power, bandwidth)
Services (cont.)
• Synchronization
– Global (per cell) vs Local (among related terminals) *
• Local is more flexible (choose local master on sign in to a common
multicast)
• IP Datacasting
– Data delivery without user awareness… ?
• Device to User (D2U) interaction
• User to Device (U2D) interaction
• Digital audio/video broadcasting/WPAN/WLAN/cellular (in off-peak
times)
• Video clips, sports highlights, movie trailers, partial data delivery as
advertisement for data service
• Infrastructure – Context Manager (CM) and Service
Manger (SM)
Integrating Heterogeneous Wireless
Technologies: A Cellular Aided Mobile Ad
hoc Network (CAMA)
Bharat Bhargava, Xiaoxin Wu, Yi Lu, Weichao
Wang
CAMA
• Use cellular network to improve ad hoc
networks (like Signaling System 7 (SS7))
– Offer QoS, and AAA (authentication,
authorization, and accounting) – why AAA ??
– Manage the connections of Mobile Ad Hoc
Users (MTs)
– Only control data goes through cellular base
stations, all user data is kept in ad hoc
network
– Routing is not fixed – managed by CAMA
CAMA example
CAMA can aid in …
• Synchronization (offer clock sync)
• Authentication (use cellular infrastructure or some other
mean like PKI)
• Power saving (estimate transmit power since distance
between MTs is known)
• Radio resource allocation (manage multiple channels
in an ad hoc network)
• Broadcasting and multicasting (broadcast through
cellular base station ??? – contradicts their claim about
all data in contained within ad hoc network)
• Finding cluster head in all clustered ad hock routing
(aid in clustered ad hoc routing that was proposed by
other research)
Feasibility analysis
• Ad hoc cell is small (because the transmit
radius is small – so 1 cell can cover all of
the ad hoc network)
• UMTS(3G) has sync and broadcast
channels (some of which could be
reserved for CAMA)
• Technology is available and cheap
• Cellular providers try create more data
services
Previous work
• Heterogeneous integrated wireless networks (how ad hoc networks
enhance cellular networks)
• Ad hoc routing with positioning
–
–
–
–
GPS, GPSR – route to peer closest to destination
VHR – position advertisement = large overhead
self positioning when GPS is not available
ABR - association beacon protocol
• Security
– Open medium, dynamic topology changing, cooperative algorithms, lack
of centralized monitoring
• Key distribution without a CA
• Routing: digital signature to authenticate, hash chain to insure hop count
information
• Architecture for intrusion detection
CAMA
• MT has GPS, and position is sent to CAMA
through cellular base station (also cellular
position service can be used) – a position of
each MT is well known
• Routing done by CAMA or MT (the study
assumes that CAMA will coordinate routes
between src. and dest. – this also avoids
periodic downlink position broadcasts, but
slower since an MT might wait for CAMA to
make its decision, also scale considerations
CAMA routing …
• Position information table per MT
– d + (delta) d <= d (required link quality
threshold)
Routing cont…
N different routes are found for S to T : S-B-H-G-T and S-C-E-I-T
1: (B,C) and (B, C)
2: (F,H,E,D) and (H,E)
3: (G, N, I, K) and (G, I)
4: (L, T, J) and (T)
Packet end-to-end delay is used for ranking (transmission + back off + propagation)
Routing cont(2)…
• Routing steps
– MT sends request to CAMA (resend in case there is no response)
– CAMA replies with a complete route including all intermediate hops +
estimated transmission powers
– Routing info is carried in the header of each packet
• Position update
– MT sends its position update in a GPS aided positioning (if a change is
relatively small no update is needed)
• Security (relates only to ad hoc network portion)
– CAMA agent can be a central security point for key distribution
– Broadcast messages when intrusion is detected
– If the GPS info is false, and there is no means to verify it – CAMA might
fail
– DoS attacks
Security cont…
• False positioning information
– Try to guess based on cellular position
– Intrusion detection
• MTs can send a failed route message when the route did not work
and CAMA can try to identify the malicious nodes
• Credit system
• Byzantine Behavior
– Encrypt and sign header info
– Report misbehaving nodes
– Message hash verifications
• Anti Jamming
– CAMA can detect the jamming condition and via MT reports and
make a decision to send client to different channel or maybe
issue a jamming alert
Simulation results
• 100 MTs (1000m X 1000m)
• Each MT moves with random direction and
random velocity between 0-3m/s
(pedestrian speed)
• Ad hoc channel 1mbit/s
• MSGPR is used for routing
• AODV = ad hoc on-demand distance
vector routing
• DSR = dynamic source routing protocol
Delivery Ratio
More Results…
More Results (2) ….
Result cont(3)…
Results cont(4)….
Conclusions
• Questions ??
• WiMax
• http://www.networkcomputing.com/showAr
ticle.jhtml?articleID=191801683
• http://www.engadget.com/2006/08/07/caltr
ain-commuter-rail-pulls-wimax-at-79-mph/
• http://moment.cs.ucsb.edu/AODV/
• http://www.cs.cmu.edu/~dmaltz/dsr.html