Abstract
Ad Hoc network is a kind of wireless and mobile network that developed in recent
years.It has a dynamic and variable topology,each node not only can move but can join
or exit the network freely.It has an acentric and infrastructureless distributed multi-hop
structure,all nodes have an equal status and act as two roles-router and node itself.
A w i reless a d h o c n e t w o r k i s a s p e c i a l s t r u c t u r e o f t h e w i r e l e s s c o m m u n i c a t i o n
network,in which the communications between the nodes rely on mutual collaboration
i n w i r e l e s s m u l t i - h o p m a n n e r , a n d t h e r e f o r e t h e n e t w o r k i s s e l f - o r g a n i z e d a n d s e l f -
managed without any infrastructure.The special type of networking makes wireless ad
hoc networks not only applicable to military communications,but also useful for areas
l i k e e n v i r o n m e n t m o n i t o r i n g , d i s a s t e r r e s c u e a n d e t c . H o w e v e r , t h e d y n a m i c n e t w o r k
topology poses severe challenges to the design of routing protocols.
The article first introduces the application,network structure,characteristic and the
essential technology of Mobile Ad Hoc Networks,as well as the thorough research on its
security problems,including the security threats,security target,security requirement that
n e t w o r k i s f a c e d w i t h . T h e n i t i n t r o d u c e s t h e e l e m e n t a r y t h e o r y o f K e y M a n a g e m e n t
technology of Mobile Ad Hoc Networks.It also summarizes and comparatively analyzes
nowadays Key Management plans.
Routing techniqu e is the key technique of Ad Hoc network and one of the mo st
impor t a nt factors affect the performance of the networ k.As the dynamic and variable
topology,those traditional ro uting protocols can n ot be appl icable to Ad Hoc network
a n d n e w r o u t i n g p r o t o c o l m u s t b e d e s i g n e d . I n r e c e n t y e a r s , s o m e s p e c i a l r o u t i n g
p r o t o c o l s f o r A d H o c n e t w o r k a p p e a r e d s u c h a s A O D V, D S R a n d D S D V. B u t t o t h e
whole fields of Ad Hoc routing techniques especially QoS routing technique, still has a
long way to go,all those routing protocols are needed to be improved as there is no any
standard protocol exists for Ad Hoc network.Ad Hoc routing technique needs a further
research and development.The dissertation studied Ad Hoc routing protocols in detail.
A s e c u r e c o m m u n i c a t i o n - e ff i c i e n t k e y a g r e e m e n t p r o t o c o l b a s e d o n t h e b i l i n e a r
pairings in Ad hoc Networks is proposed. In this protocol, the dynamicity of the
networks is considered and the 1-hop assumption is weakened by employing
h i e r a r c h i c a l r o u t i n g t e c h n i q u e s t o e n s u r e t h a t t h e l o g i c a l m o d e l o f k e y a g r e e m e n t
consist with the actual topology of networks. As a result, the communication overhead
is reduced. The analysis result shows that the proposed scheme is applicable to ad hoc
networks with large size.
K e y w o r d s : a d h o c n e t w o r k s ; k e y a g r e e m e n t ; h i e r a r c h y r o u t i n g ;
bilinear pairings
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