A Survey on Key Management of Identity-based Schemes in Mobile Ad Hoc Networks
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paper_title: Toward secure key distribution in truly ad-hoc networks

paper_content:

Ad-hoc networks - and in particular wireless mobile ad-hoc networks $have unique characteristics and constraints that make traditional cryptographic mechanisms and assumptions inappropriate. In particular it may not be warranted to assume pre-existing shared secrets between members of the network or the presence of a common PKI. Thus, the issue of key distribution in ad-hoc networks represents an important problem. Unfortunately, this issue has been largely ignored; as an example, most protocols for secure ad-hoc routing assume that key distribution has already taken place. Traditional key distribution schemes either do not apply in an ad-hoc scenario or are not efficient enough for small, resource-constrained devices. We propose to combine efficient techniques from identity-based (ID-based) and threshold cryptography to provide a mechanism that enables flexible and efficient key distribution while respecting the constraints of ad-hoc networks. We also discuss the available mechanisms and their suitability for the proposed task.
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paper_title: A Survey of Applications of Identity-Based Cryptography in Mobile Ad-Hoc Networks

paper_content:

Security in mobile ad-hoc networks (MANETs) continues to attract attention after years of research. Recent advances in identity-based cryptography (IBC) sheds light on this problem and has become popular as a solution base. We present a comprehensive picture and capture the state of the art of IBC security applications in MANETs based on a survey of publications on this topic since the emergence of IBC in 2001. In this paper, we also share insights into open research problems and point out interesting future directions in this area.
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paper_title: A Survey of Identity-Based Cryptography

paper_content:

In this paper, we survey the state of research on identity-based cryptography. We start from reviewing the basic concepts of identity-based encryption and signature schemes, and subsequently review some important identity-based cryptographic schemes based on the bilinear pairing, a computational primitive widely used to build up various identity-based cryptographic schemes in the current literature. We also survey the cryptographic schemes such as a “certificate-based encryption scheme” and a “public key encryption scheme with keyword search”, which were able to be constructed thanks to the successful realization of identity-based encryption. Finally, we discuss how feasible and under what conditions identity-based cryptography may be used in current and future environments and propose some interesting open problems concerning with practical and theoretical aspects of identity-based cryptography.
---
paper_title: Toward secure key distribution in truly ad-hoc networks

paper_content:

Ad-hoc networks - and in particular wireless mobile ad-hoc networks $have unique characteristics and constraints that make traditional cryptographic mechanisms and assumptions inappropriate. In particular it may not be warranted to assume pre-existing shared secrets between members of the network or the presence of a common PKI. Thus, the issue of key distribution in ad-hoc networks represents an important problem. Unfortunately, this issue has been largely ignored; as an example, most protocols for secure ad-hoc routing assume that key distribution has already taken place. Traditional key distribution schemes either do not apply in an ad-hoc scenario or are not efficient enough for small, resource-constrained devices. We propose to combine efficient techniques from identity-based (ID-based) and threshold cryptography to provide a mechanism that enables flexible and efficient key distribution while respecting the constraints of ad-hoc networks. We also discuss the available mechanisms and their suitability for the proposed task.
---
paper_title: Identity-based cryptosystems and signature schemes

paper_content:

In this paper we introduce a novel type of cryptographic scheme, which enables any pair of users to communicate securely and to verify each other’s signatures without exchanging private or public keys, without keeping key directories, and without using the services of a third party. The scheme assumes the existence of trusted key generation centers, whose sole purpose is to give each user a personalized smart card when he first joins the network. The information embedded in this card enables the user to sign and encrypt the messages he sends and to decrypt and verify the messages he receives in a totally independent way, regardless of the identity of the other party. Previously issued cards do not have to be updated when new users join the network, and the various centers do not have to coordinate their activities or even to keep a user list. The centers can be closed after all the cards are issued, and the network can continue to function in a completely decentralized way for an indefinite period.
---
paper_title: Short Signatures from the Weil Pairing

paper_content:

We introduce a short signature scheme based on the Computational Diffie–Hellman assumption on certain elliptic and hyperelliptic curves. For standard security parameters, the signature length is about half that of a DSA signature with a similar level of security. Our short signature scheme is designed for systems where signatures are typed in by a human or are sent over a low-bandwidth channel. We survey a number of properties of our signature scheme such as signature aggregation and batch verification.
---
paper_title: Identity-based encryption from the Weil pairing

paper_content:

We propose a fully functional identity-based encryption (IBE) scheme. The scheme has chosen ciphertext security in the random oracle model assuming a variant of the computational Diffie--Hellman problem. Our system is based on bilinear maps between groups. The Weil pairing on elliptic curves is an example of such a map. We give precise definitions for secure IBE schemes and give several applications for such systems.
---
paper_title: Toward secure key distribution in truly ad-hoc networks

paper_content:

Ad-hoc networks - and in particular wireless mobile ad-hoc networks $have unique characteristics and constraints that make traditional cryptographic mechanisms and assumptions inappropriate. In particular it may not be warranted to assume pre-existing shared secrets between members of the network or the presence of a common PKI. Thus, the issue of key distribution in ad-hoc networks represents an important problem. Unfortunately, this issue has been largely ignored; as an example, most protocols for secure ad-hoc routing assume that key distribution has already taken place. Traditional key distribution schemes either do not apply in an ad-hoc scenario or are not efficient enough for small, resource-constrained devices. We propose to combine efficient techniques from identity-based (ID-based) and threshold cryptography to provide a mechanism that enables flexible and efficient key distribution while respecting the constraints of ad-hoc networks. We also discuss the available mechanisms and their suitability for the proposed task.
---
paper_title: Threshold Cryptosystems

paper_content:

In a society oriented cryptography it is better to have a public key for the company (organization) than having one for each individual employee [Des88]. Certainly in emergency situations, power is shared in many organizations. Solutions to this problem were presented [Des88], based on [GMW87], but are completely impractical and interactive. In this paper practical non-interactive public key systems are proposed which allow the reuse of the shared secret key since the key is not revealed either to insiders or to outsiders.
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paper_title: Identity-based key distribution for mobile Ad Hoc networks

paper_content:

An identity-based cryptosystem can make a special contribution to building key distribution and management architectures in resource-constrained mobile ad hoc networks since it does not suffer from certificate management problems. In this paper, based on a lightweight cryptosystem, elliptic curve cryptography (ECC), we propose an identity-based distributed key-distribution protocol for mobile ad hoc networks. In this protocol, using secret sharing, we build a virtual private key generator which calculates one part of a user's secret key and sends it to the user via public channels, while, the other part of the secret key is generated by the user. So, the secret key of the user is generated collaboratively by the virtual authority and the user. Each has half of the secret information about the secret key of the user. Thus there is no secret key distribution problem. In addition, the user's secret key is known only to the user itself, therefore there is no key escrow.
---
paper_title: An efficient and non-interactive hierarchical key agreement protocol

paper_content:

The non-interactive identity-based key agreement schemes are believed to be applicable to mobile ad-hoc networks (MANETs) that have a hierarchical structure such as hierarchical military MANETs. It was observed by Gennaro et al. (2008) that there is still an open problem on the security of the existing schemes, i.e., how to achieve the desirable security against corrupted nodes in the higher levels of a hierarchy? In this paper, we propose a novel and very efficient non-interactive hierarchical identity-based key agreement scheme that solves the open problem and outperforms all existing schemes in terms of computational efficiency and data storage.
---
paper_title: A Certificateless Key Management Scheme in Mobile Ad Hoc Networks

paper_content:

Key management plays an important role in the security of today's information technology, especially in wireless and mobile environments like mobile ad hoc networks (MANETs) in which key management has received more and more attention for the difficulty to be implemented in such dynamic network. Traditional key management schemes are mainly based on PKI and identity-based public key cryptography (ID-PKC), which suffers from the computational costs of certificate verification and the key escrow problem. In this paper, we present a novel distributed key management scheme, a combination of certificateless public key cryptography (CL-PKC) and threshold cryptography, which not only eliminates the need for certificate-based public key distribution and the key escrow problem but also prevents single point of failure.
---
paper_title: TIDS: threshold and identity-based security scheme for wireless ad hoc networks ☆

paper_content:

Abstract As various applications of wireless ad hoc network have been proposed, security has received increasing attentions as one of the critical research challenges. In this paper, we consider the security issues at network layer, wherein routing and packet forwarding are the main operations. We propose a novel efficient security scheme in order to provide various security characteristics, such as authentication , confidentiality , integrity and non-repudiation for wireless ad hoc networks. In our scheme, we deploy the recently developed concepts of identity-based signcryption and threshold secret sharing . We describe our proposed security solution in context of dynamic source routing (DSR) protocol. Without any assumption of pre-fixed trust relationship between nodes, the ad hoc network works in a self-organizing way to provide key generation and key management services using threshold secret sharing algorithm, which effectively solves the problem of single point of failure in the traditional public-key infrastructure (PKI) supported system. The identity-based signcryption mechanism is applied here not only to provide end-to-end authenticity and confidentiality in a single step, but also to save network bandwidth and computational power of wireless nodes. Moreover, one-way hash chain is used to protect hop-by-hop transmission.
---
paper_title: Virtual private key generator based escrow-free certificateless public key cryptosystem for mobile ad hoc networks

paper_content:

A certificateless public key cryptosystem can make a special contribution to building key distribution and management architecture in resource-constrained mobile ad hoc networks (MANETs) because it has no separate certificate and no complex certificate management problems. In this paper, we present a virtual private key generator (VPKG)-based escrow-free certificateless public key cryptosystem as a novel combination of certificateless and threshold cryptography. Using secret sharing, we build a VPKG whose members collaboratively calculate the partial private key and send it to the user via public channels. The private key of a user is generated jointly by the VPKG and the user. Each of them has “half” of the secret information about the private key of the user. In addition, binding a user's public key with its identity and partial private key, respectively, raises our schemes to the same trust level as is enjoyed in a traditional public key infrastructure. We also show that the proposed scheme is secure against public key replacement attacks and passive attacks. Copyright © 2012 John Wiley & Sons, Ltd.
---
paper_title: Toward secure key distribution in truly ad-hoc networks

paper_content:

Ad-hoc networks - and in particular wireless mobile ad-hoc networks $have unique characteristics and constraints that make traditional cryptographic mechanisms and assumptions inappropriate. In particular it may not be warranted to assume pre-existing shared secrets between members of the network or the presence of a common PKI. Thus, the issue of key distribution in ad-hoc networks represents an important problem. Unfortunately, this issue has been largely ignored; as an example, most protocols for secure ad-hoc routing assume that key distribution has already taken place. Traditional key distribution schemes either do not apply in an ad-hoc scenario or are not efficient enough for small, resource-constrained devices. We propose to combine efficient techniques from identity-based (ID-based) and threshold cryptography to provide a mechanism that enables flexible and efficient key distribution while respecting the constraints of ad-hoc networks. We also discuss the available mechanisms and their suitability for the proposed task.
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paper_title: Strongly-Resilient and Non-Interactive Hierarchical Key-Agreement in MANETs

paper_content:

Key agreement is a fundamental security functionality by which pairs of nodes agree on shared keys to be used for protecting their pairwise communications. In this work we study key-agreement schemes that are well-suited for the mobile network environment. Specifically, we describe schemes with the following characteristics: ::: ::: ::: Non-interactive:any two nodes can compute a unique shared secret key without interaction; ::: Identity-based:to compute the shared secret key, each node only needs its own secret key and the identity of its peer; ::: Hierarchical:the scheme is decentralized through a hierarchy where intermediate nodes in the hierarchy can derive the secret keys for each of its children without any limitations or prior knowledge on the number of such children or their identities; ::: Resilient:the scheme is fully resilient against compromise of any number of leavesin the hierarchy, and of a threshold number of nodes in each of the upper levels of the hierarchy. ::: ::: ::: ::: Several schemes in the literature have three of these four properties, but the schemes in this work are the first to possess all four. This makes them well-suited for environments such as MANETs and tactical networks which are very dynamic, have significant bandwidth and energy constraints, and where many nodes are vulnerable to compromise. We provide rigorous analysis of the proposed schemes and discuss implementations aspects.
---
paper_title: A new scheme for key management in ad hoc networks

paper_content:

Robust key management is one of the most crucial technologies for security of ad hoc networks. In this paper, a new scheme for key management is proposed using identity-based (ID-based) signcryption and threshold cryptography. It enables flexible and efficient key management while respecting the constraints of ad hoc networks. In our new scheme, public key certificates are not needed and every client uses its identity as its public key. It greatly decreases the need of computing and storage abilities of clients' terminals, as well as communication cost for system key management.
---
paper_title: A practical scheme for non-interactive verifiable secret sharing

paper_content:

This paper presents an extremely efficient, non-interactive protocol for verifiable secret sharing. Verifiable secret sharing (VSS) is a way of bequeathing information to a set of processors such that a quorum of processors is needed to access the information. VSS is a fundamental tool of cryptography and distributed computing. Seemingly difficult problems such as secret bidding, fair voting, leader election, and flipping a fair coin have simple one-round reductions to VSS. There is a constant-round reduction from Byzantine Agreement to non-interactive VSS. Non-interactive VSS provides asynchronous networks with a constant-round simulation of simultaneous broadcast networks whenever even a bare majority of processors are good. VSS is constantly repeated in the simulation of fault-free protocols by faulty systems. As verifiable secret sharing is a bottleneck for so many results, it is essential to find efficient solutions.
---
paper_title: Halo: A Hierarchical Identity-Based Public Key Infrastructure for Peer-to-Peer Opportunistic Collaboration

paper_content:

The lack of information security protection for peer-to-peer systems has hampered the use of this robust and scalable technology in sensitive applications. The security weakness is rooted in the server-less architecture and the demand driven ad-hoc operation scenarios of peer-to-peer systems. Together, they prohibit scalable key management using traditional symmetric/ asymmetric cryptographic techniques. The advent of hierarchical identity-based cryptography and thresholded/joint secret sharing offers a possible solution to this problem. In this paper, we present the design of Halo, a hierarchical identity-based public key infrastructure that uses these novel technologies to perform recursive instantiation of private key generators and establish a trust hierarchy with unlimited number of levels. The PKI thus enables the employment of hierarchical identity-based public key encryption, signature, and signcryption for the protection of peer-to-peer applications. The effort to implement a proof-of-concept prototype as a JXTA service module was also discussed.
---
paper_title: Public key cryptography sans certificates in ad hoc networks

paper_content:

Several researchers have proposed the use of threshold cryptographic model to enable secure communication in ad hoc networks without the need of a trusted center. In this model, the system remains secure even in the presence of a certain threshold t of corrupted/malicious nodes. In this paper, we show how to perform necessary public key operations without node-specific certificates in ad hoc networks. These operations include pair-wise key establishment, signing, and encryption. We achieve this by using Feldman's verifiable polynomial secret sharing (VSS) as a key distribution scheme and treating the secret shares as the private keys. Unlike in the standard public key cryptography, where entities have independent private/public key pairs, in the proposed scheme the private keys are related (they are points on a polynomial of degree t) and each public key can be computed from the public VSS information and node identifier. We show that such related keys can still be securely used for standard signature and encryption operations (using resp. Schnorr signatures and ElGamal encryption) and for pairwise key establishment, as long as there are no more that t collusions/corruptions in the system. The proposed usage of shares as private keys can also be viewed as a threshold-tolerant identity-based cryptosystem under standard (discrete logarithm based) assumptions.
---
paper_title: Threshold and identity-based key management and authentication for wireless ad hoc networks

paper_content:

As various applications of wireless ad hoc network have been proposed, security has become one of the big research challenges and is receiving increasing attention. In this paper, we propose a distributed key management and authentication approach by deploying the recently developed concepts of identity-based cryptography and threshold secret sharing. Without any assumption of prefixed trust relationship between nodes, the ad hoc network works in a self-organizing way to provide the key generation and key management service, which effectively solves the problem of single point of failure in the traditional public key infrastructure (PKI)-supported system. The identity-based cryptography mechanism is applied here not only to provide end-to-end authenticity and confidentiality, but also to save network bandwidth and computational power of wireless nodes.
---
paper_title: AC-PKI: anonymous and certificateless public-key infrastructure for mobile ad hoc networks

paper_content:

This paper studies public-key management, a fundamental problem in providing security support for mobile ad hoc networks. The infrastructureless nature and network dynamics of ad hoc networks make the conventional certificate-based public-key solutions less suitable. To tackle this problem, we propose a novel anonymous and certificateless public-key infrastructure (AC-PKI) for ad hoc networks. AC-PKI enables public-key services with certificateless public keys and thus avoids the complicated certificate management inevitable in conventional certificate-based solutions. To satisfy the demand for private keys during network operation, we employ the secret-sharing technique to distribute a system master-key among a preselected set of nodes, called D-PKG, which offer a collaborative private-key-generation service. In addition, we identify pinpoint attacks against D-PKG and propose anonymizing D-PKG as the countermeasure. Moreover, we determine the optimal secret-sharing parameters to achieve the maximum security.
---
paper_title: TIDS: threshold and identity-based security scheme for wireless ad hoc networks ☆

paper_content:

Abstract As various applications of wireless ad hoc network have been proposed, security has received increasing attentions as one of the critical research challenges. In this paper, we consider the security issues at network layer, wherein routing and packet forwarding are the main operations. We propose a novel efficient security scheme in order to provide various security characteristics, such as authentication , confidentiality , integrity and non-repudiation for wireless ad hoc networks. In our scheme, we deploy the recently developed concepts of identity-based signcryption and threshold secret sharing . We describe our proposed security solution in context of dynamic source routing (DSR) protocol. Without any assumption of pre-fixed trust relationship between nodes, the ad hoc network works in a self-organizing way to provide key generation and key management services using threshold secret sharing algorithm, which effectively solves the problem of single point of failure in the traditional public-key infrastructure (PKI) supported system. The identity-based signcryption mechanism is applied here not only to provide end-to-end authenticity and confidentiality in a single step, but also to save network bandwidth and computational power of wireless nodes. Moreover, one-way hash chain is used to protect hop-by-hop transmission.
---
paper_title: An Identity-Based Signature from Gap Diffie-Hellman Groups

paper_content:

In this paper we propose an identity(ID)-based signature scheme using gap Diffie-Hellman (GDH) groups. Our scheme is proved secure against existential forgery on adaptively chosen message and ID attack under the random oracle model. Using GDH groups obtained from bilinear pairings, as a special case of our scheme, we obtain an ID-based signature scheme that shares the same system parameters with the ID-based encryption scheme (BF-IBE) by Boneh and Franklin [BF01], and is as efficient as the BF-IBE. Combining our signature scheme with the BF-IBE yields a complete solution of an ID-based public key system. It can be an alternative for certificate-based public key infrastructures, especially when efficient key management and moderate security are required.
---
paper_title: Toward secure key distribution in truly ad-hoc networks

paper_content:

Ad-hoc networks - and in particular wireless mobile ad-hoc networks $have unique characteristics and constraints that make traditional cryptographic mechanisms and assumptions inappropriate. In particular it may not be warranted to assume pre-existing shared secrets between members of the network or the presence of a common PKI. Thus, the issue of key distribution in ad-hoc networks represents an important problem. Unfortunately, this issue has been largely ignored; as an example, most protocols for secure ad-hoc routing assume that key distribution has already taken place. Traditional key distribution schemes either do not apply in an ad-hoc scenario or are not efficient enough for small, resource-constrained devices. We propose to combine efficient techniques from identity-based (ID-based) and threshold cryptography to provide a mechanism that enables flexible and efficient key distribution while respecting the constraints of ad-hoc networks. We also discuss the available mechanisms and their suitability for the proposed task.
---
paper_title: Reducing the cost of security in link-state routing

paper_content:

Security in link-state routing protocols is a feature that is both desirable and costly. This paper examines the cost of security and presents two techniques for efficient and secure processing of link state updates. The first technique is geared towards a relatively stable internetwork environment while the second is designed with a more volatile environment in mind.
---
paper_title: Identity-based cryptosystems and signature schemes

paper_content:

In this paper we introduce a novel type of cryptographic scheme, which enables any pair of users to communicate securely and to verify each other’s signatures without exchanging private or public keys, without keeping key directories, and without using the services of a third party. The scheme assumes the existence of trusted key generation centers, whose sole purpose is to give each user a personalized smart card when he first joins the network. The information embedded in this card enables the user to sign and encrypt the messages he sends and to decrypt and verify the messages he receives in a totally independent way, regardless of the identity of the other party. Previously issued cards do not have to be updated when new users join the network, and the various centers do not have to coordinate their activities or even to keep a user list. The centers can be closed after all the cards are issued, and the network can continue to function in a completely decentralized way for an indefinite period.
---
paper_title: A new scheme for key management in ad hoc networks

paper_content:

Robust key management is one of the most crucial technologies for security of ad hoc networks. In this paper, a new scheme for key management is proposed using identity-based (ID-based) signcryption and threshold cryptography. It enables flexible and efficient key management while respecting the constraints of ad hoc networks. In our new scheme, public key certificates are not needed and every client uses its identity as its public key. It greatly decreases the need of computing and storage abilities of clients' terminals, as well as communication cost for system key management.
---
paper_title: A Key Management Scheme for Ad Hoc Networks

paper_content:

An improved key management scheme is proposed for Ad Hoc network. The improved scheme adopts combined technologies of verifiable secret sharing,public key encryption and random numbers. The analysis results show that the improved scheme could further raise security performance while reduces computation cost.
---
paper_title: Identity-based encryption from the Weil pairing

paper_content:

We propose a fully functional identity-based encryption (IBE) scheme. The scheme has chosen ciphertext security in the random oracle model assuming a variant of the computational Diffie--Hellman problem. Our system is based on bilinear maps between groups. The Weil pairing on elliptic curves is an example of such a map. We give precise definitions for secure IBE schemes and give several applications for such systems.
---
paper_title: Threshold and identity-based key management and authentication for wireless ad hoc networks

paper_content:

As various applications of wireless ad hoc network have been proposed, security has become one of the big research challenges and is receiving increasing attention. In this paper, we propose a distributed key management and authentication approach by deploying the recently developed concepts of identity-based cryptography and threshold secret sharing. Without any assumption of prefixed trust relationship between nodes, the ad hoc network works in a self-organizing way to provide the key generation and key management service, which effectively solves the problem of single point of failure in the traditional public key infrastructure (PKI)-supported system. The identity-based cryptography mechanism is applied here not only to provide end-to-end authenticity and confidentiality, but also to save network bandwidth and computational power of wireless nodes.
---
paper_title: Efficient signature generation by smart cards

paper_content:

We present a new public-key signature scheme and a corresponding authentication scheme that are based on discrete logarithms in a subgroup of units in ? p where p is a sufficiently large prime, e.g., p ? 2512. A key idea is to use for the base of the discrete logarithm an integer ? in ? p such that the order of ? is a sufficiently large prime q, e.g., q ? 2140. In this way we improve the ElGamal signature scheme in the speed of the procedures for the generation and the verification of signatures and also in the bit length of signatures. We present an efficient algorithm that preprocesses the exponentiation of a random residue modulo p.
---
paper_title: An Identity-Based Signature from Gap Diffie-Hellman Groups

paper_content:

In this paper we propose an identity(ID)-based signature scheme using gap Diffie-Hellman (GDH) groups. Our scheme is proved secure against existential forgery on adaptively chosen message and ID attack under the random oracle model. Using GDH groups obtained from bilinear pairings, as a special case of our scheme, we obtain an ID-based signature scheme that shares the same system parameters with the ID-based encryption scheme (BF-IBE) by Boneh and Franklin [BF01], and is as efficient as the BF-IBE. Combining our signature scheme with the BF-IBE yields a complete solution of an ID-based public key system. It can be an alternative for certificate-based public key infrastructures, especially when efficient key management and moderate security are required.
---
paper_title: A practical scheme for non-interactive verifiable secret sharing

paper_content:

This paper presents an extremely efficient, non-interactive protocol for verifiable secret sharing. Verifiable secret sharing (VSS) is a way of bequeathing information to a set of processors such that a quorum of processors is needed to access the information. VSS is a fundamental tool of cryptography and distributed computing. Seemingly difficult problems such as secret bidding, fair voting, leader election, and flipping a fair coin have simple one-round reductions to VSS. There is a constant-round reduction from Byzantine Agreement to non-interactive VSS. Non-interactive VSS provides asynchronous networks with a constant-round simulation of simultaneous broadcast networks whenever even a bare majority of processors are good. VSS is constantly repeated in the simulation of fault-free protocols by faulty systems. As verifiable secret sharing is a bottleneck for so many results, it is essential to find efficient solutions.
---
paper_title: Identity-based encryption from the Weil pairing

paper_content:

We propose a fully functional identity-based encryption (IBE) scheme. The scheme has chosen ciphertext security in the random oracle model assuming a variant of the computational Diffie--Hellman problem. Our system is based on bilinear maps between groups. The Weil pairing on elliptic curves is an example of such a map. We give precise definitions for secure IBE schemes and give several applications for such systems.
---
paper_title: Public key cryptography sans certificates in ad hoc networks

paper_content:

Several researchers have proposed the use of threshold cryptographic model to enable secure communication in ad hoc networks without the need of a trusted center. In this model, the system remains secure even in the presence of a certain threshold t of corrupted/malicious nodes. In this paper, we show how to perform necessary public key operations without node-specific certificates in ad hoc networks. These operations include pair-wise key establishment, signing, and encryption. We achieve this by using Feldman's verifiable polynomial secret sharing (VSS) as a key distribution scheme and treating the secret shares as the private keys. Unlike in the standard public key cryptography, where entities have independent private/public key pairs, in the proposed scheme the private keys are related (they are points on a polynomial of degree t) and each public key can be computed from the public VSS information and node identifier. We show that such related keys can still be securely used for standard signature and encryption operations (using resp. Schnorr signatures and ElGamal encryption) and for pairwise key establishment, as long as there are no more that t collusions/corruptions in the system. The proposed usage of shares as private keys can also be viewed as a threshold-tolerant identity-based cryptosystem under standard (discrete logarithm based) assumptions.
---
paper_title: Identity-based key distribution for mobile Ad Hoc networks

paper_content:

An identity-based cryptosystem can make a special contribution to building key distribution and management architectures in resource-constrained mobile ad hoc networks since it does not suffer from certificate management problems. In this paper, based on a lightweight cryptosystem, elliptic curve cryptography (ECC), we propose an identity-based distributed key-distribution protocol for mobile ad hoc networks. In this protocol, using secret sharing, we build a virtual private key generator which calculates one part of a user's secret key and sends it to the user via public channels, while, the other part of the secret key is generated by the user. So, the secret key of the user is generated collaboratively by the virtual authority and the user. Each has half of the secret information about the secret key of the user. Thus there is no secret key distribution problem. In addition, the user's secret key is known only to the user itself, therefore there is no key escrow.
---
paper_title: A Certificateless Key Management Scheme in Mobile Ad Hoc Networks

paper_content:

Key management plays an important role in the security of today's information technology, especially in wireless and mobile environments like mobile ad hoc networks (MANETs) in which key management has received more and more attention for the difficulty to be implemented in such dynamic network. Traditional key management schemes are mainly based on PKI and identity-based public key cryptography (ID-PKC), which suffers from the computational costs of certificate verification and the key escrow problem. In this paper, we present a novel distributed key management scheme, a combination of certificateless public key cryptography (CL-PKC) and threshold cryptography, which not only eliminates the need for certificate-based public key distribution and the key escrow problem but also prevents single point of failure.
---
paper_title: Virtual private key generator based escrow-free certificateless public key cryptosystem for mobile ad hoc networks

paper_content:

A certificateless public key cryptosystem can make a special contribution to building key distribution and management architecture in resource-constrained mobile ad hoc networks (MANETs) because it has no separate certificate and no complex certificate management problems. In this paper, we present a virtual private key generator (VPKG)-based escrow-free certificateless public key cryptosystem as a novel combination of certificateless and threshold cryptography. Using secret sharing, we build a VPKG whose members collaboratively calculate the partial private key and send it to the user via public channels. The private key of a user is generated jointly by the VPKG and the user. Each of them has “half” of the secret information about the private key of the user. In addition, binding a user's public key with its identity and partial private key, respectively, raises our schemes to the same trust level as is enjoyed in a traditional public key infrastructure. We also show that the proposed scheme is secure against public key replacement attacks and passive attacks. Copyright © 2012 John Wiley & Sons, Ltd.
---
paper_title: Identity-based encryption from the Weil pairing

paper_content:

We propose a fully functional identity-based encryption (IBE) scheme. The scheme has chosen ciphertext security in the random oracle model assuming a variant of the computational Diffie--Hellman problem. Our system is based on bilinear maps between groups. The Weil pairing on elliptic curves is an example of such a map. We give precise definitions for secure IBE schemes and give several applications for such systems.
---
paper_title: Hierarchical routing for multi-layer ad-hoc wireless networks with UAVs

paper_content:

Routing scalability in multi-hop wireless networks faces many challenges. The spatial concurrency constraint on nearby nodes sharing the same channel is the fundamental limitation. A previous theoretical study shows that the throughput furnished to each user is rapidly reduced as network size is increased. In order to solve this problem, we extended the hierarchical state routing scheme to a hierarchical multilayer environment. With the hierarchical approach, many problems caused by "flat" multi-hopping disappear. In the real battlefield, a multi-level physical heterogeneous network with UAVs provides an ideal support for the multi-area theater with a large number of fighting units. Extended hierarchical state relating (EHSR) shows very promising results in this hierarchical infrastructure.
---
paper_title: An efficient and non-interactive hierarchical key agreement protocol

paper_content:

The non-interactive identity-based key agreement schemes are believed to be applicable to mobile ad-hoc networks (MANETs) that have a hierarchical structure such as hierarchical military MANETs. It was observed by Gennaro et al. (2008) that there is still an open problem on the security of the existing schemes, i.e., how to achieve the desirable security against corrupted nodes in the higher levels of a hierarchy? In this paper, we propose a novel and very efficient non-interactive hierarchical identity-based key agreement scheme that solves the open problem and outperforms all existing schemes in terms of computational efficiency and data storage.
---
paper_title: Toward Hierarchical Identity-Based Encryption

paper_content:

We introduce the concept of hierarchical identity-based encryption (HIBE) schemes, give precise definitions of their security and mention some applications. A two-level HIBE (2-HIBE) scheme consists of a root private key generator (PKG), domain PKGs and users, all of which are associated with primitive IDs (PIDs) that are arbitrary strings. A user's public key consists of their PID and their domain's PID (in whole called an address). In a regular IBE (which corresponds to a 1-HIBE) scheme, there is only one PKG that distributes private keys to each user (whose public keys are their PID). In a 2-HIBE, users retrieve their private key from their domain PKG. Domain PKGs can compute the private key of any user in their domain, provided they have previously requested their domain secret key from the root PKG (who possesses a master secret). We can go beyond two levels by adding subdomains, subsubdomains, and so on. We present a two-level system with total collusion resistance at the upper (domain) level and partial collusion resistance at the lower (user) level, which has chosen-ciphertext security in the random-oracle model.
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paper_title: New Strategies for Revocation in Ad-Hoc Networks

paper_content:

Responding to misbehavior in ad-hoc and sensor networks is difficult. We propose new techniques for deciding when to remove nodes in a decentralized manner. Rather than blackballing nodes that misbehave, a more efficient approach turns out to be reelection - requiring nodes to secure a majority or plurality of approval from their neighbors at regular intervals. This can be implemented in a standard model of voting in which the nodes form a club, or in a lightweight scheme where each node periodically broadcasts a 'buddy list' of neighbors it trusts. This allows much greater flexibility of trust strategies than a predetermined voting mechanism. We then consider an even more radical strategy still - suicide attacks - in which a node on perceiving another node to be misbehaving simply declares both of them to be dead. Other nodes thereafter ignore them both. Suicide attacks, found in a number of contexts in nature from bees to helper T-cells, turn out to be more efficient still for an interesting range of system parameters.
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paper_title: TIDS: threshold and identity-based security scheme for wireless ad hoc networks ☆

paper_content:

Abstract As various applications of wireless ad hoc network have been proposed, security has received increasing attentions as one of the critical research challenges. In this paper, we consider the security issues at network layer, wherein routing and packet forwarding are the main operations. We propose a novel efficient security scheme in order to provide various security characteristics, such as authentication , confidentiality , integrity and non-repudiation for wireless ad hoc networks. In our scheme, we deploy the recently developed concepts of identity-based signcryption and threshold secret sharing . We describe our proposed security solution in context of dynamic source routing (DSR) protocol. Without any assumption of pre-fixed trust relationship between nodes, the ad hoc network works in a self-organizing way to provide key generation and key management services using threshold secret sharing algorithm, which effectively solves the problem of single point of failure in the traditional public-key infrastructure (PKI) supported system. The identity-based signcryption mechanism is applied here not only to provide end-to-end authenticity and confidentiality in a single step, but also to save network bandwidth and computational power of wireless nodes. Moreover, one-way hash chain is used to protect hop-by-hop transmission.
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paper_title: The capacity of wireless networks

paper_content:

When n identical randomly located nodes, each capable of transmitting at W bits per second and using a fixed range, form a wireless network, the throughput /spl lambda/(n) obtainable by each node for a randomly chosen destination is /spl Theta/(W//spl radic/(nlogn)) bits per second under a noninterference protocol. If the nodes are optimally placed in a disk of unit area, traffic patterns are optimally assigned, and each transmission's range is optimally chosen, the bit-distance product that can be transported by the network per second is /spl Theta/(W/spl radic/An) bit-meters per second. Thus even under optimal circumstances, the throughput is only /spl Theta/(W//spl radic/n) bits per second for each node for a destination nonvanishingly far away. Similar results also hold under an alternate physical model where a required signal-to-interference ratio is specified for successful receptions. Fundamentally, it is the need for every node all over the domain to share whatever portion of the channel it is utilizing with nodes in its local neighborhood that is the reason for the constriction in capacity. Splitting the channel into several subchannels does not change any of the results. Some implications may be worth considering by designers. Since the throughput furnished to each user diminishes to zero as the number of users is increased, perhaps networks connecting smaller numbers of users, or featuring connections mostly with nearby neighbors, may be more likely to be find acceptance.
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paper_title: Provably Secure Certificate-based Signature Scheme for Ad Hoc Networks

paper_content:

Certificate-based cryptography proposed by Gentry in Eurocrypt 2003 combines the advantages of traditional public key cryptography (PKI) and identity-based cryptography, and removes the certificate management problem and the private key escrow security concern. Based on computational Diffie-Hellman assumption, a certificate-based signature scheme is constructed to insure the security of communication in mobile Ad hoc networks,. The security of the scheme is proved under the Random Oracle Model. The scheme is also efficient, since the signing algorithm does not need the computation of the bilinear pairing and the verification algorithm needs that computation only once. Thus it is particularly useful in Ad hoc networks.
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paper_title: DSR : The Dynamic Source Routing Protocol for Multi-Hop Wireless Ad Hoc Networks

paper_content:

The Dynamic Source Routing protocol (DSR) is a simple and efficient routing protocol designed specifically for use in multi-hop wireless ad hoc networks of mobile nodes. DSR allows the network to be completely self-organizing and self-configuring, without the need for any existing network infrastructure or administration. The protocol is composed of the two mechanisms of Route Discovery and Route Maintenance, which work together to allow nodes to discover and maintain source routes to arbitrary destinations in the ad hoc network. The use of source routing allows packet routing to be trivially loop-free, avoids the need for up-to-date routing information in the intermediate nodes through which packets are forwarded, and allows nodes forwarding or overhearing packets to cache the routing information in them for their own future use. All aspects of the protocol operate entirely on-demand, allowing the routing packet overhead of DSR to scale automatically to only that needed to react to changes in the routes currently in use. We have evaluated the operation of DSR through detailed simulation on a variety of movement and communication patterns, and through implementation and significant experimentation in a physical outdoor ad hoc networking testbed we have constructed in Pittsburgh, and have demonstrated the excellent performance of the protocol. In this chapter, we describe the design of DSR and provide a summary of some of our simulation and testbed implementation results for the protocol.
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paper_title: Strongly-Resilient and Non-Interactive Hierarchical Key-Agreement in MANETs

paper_content:

Key agreement is a fundamental security functionality by which pairs of nodes agree on shared keys to be used for protecting their pairwise communications. In this work we study key-agreement schemes that are well-suited for the mobile network environment. Specifically, we describe schemes with the following characteristics: ::: ::: ::: Non-interactive:any two nodes can compute a unique shared secret key without interaction; ::: Identity-based:to compute the shared secret key, each node only needs its own secret key and the identity of its peer; ::: Hierarchical:the scheme is decentralized through a hierarchy where intermediate nodes in the hierarchy can derive the secret keys for each of its children without any limitations or prior knowledge on the number of such children or their identities; ::: Resilient:the scheme is fully resilient against compromise of any number of leavesin the hierarchy, and of a threshold number of nodes in each of the upper levels of the hierarchy. ::: ::: ::: ::: Several schemes in the literature have three of these four properties, but the schemes in this work are the first to possess all four. This makes them well-suited for environments such as MANETs and tactical networks which are very dynamic, have significant bandwidth and energy constraints, and where many nodes are vulnerable to compromise. We provide rigorous analysis of the proposed schemes and discuss implementations aspects.
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paper_title: A hierarchical identity based key management scheme in tactical Mobile Ad Hoc Networks

paper_content:

Hierarchical key management schemes would serve well for military applications where the organization of the network is already hierarchical in nature. Most of the existing key management schemes concentrate only on network structures and key allocation algorithms, ignoring attributes of the nodes themselves. Due to the distributed and dynamic nature of MANETs, it is possible to show that there is a security benefit to be attained when the node states are considered in the process of constructing a private key generator (PKG). In this paper, we propose a distributed hierarchical key management scheme in which nodes can get their keys updated either from their parent nodes or a threshold of sibling nodes. The proposed scheme can select the best nodes to be used as PGKs from all available ones considering their security conditions and energy states. Simulation results show that the proposed scheme can decrease network compromising probability and increase network lifetime.
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paper_title: Routing Protocols for Self-Organizing Hierarchical Ad-Hoc Wireless Networks

paper_content:

A novel self-organizing hierarchical architecture is proposed for improving the scalability properties of adhoc wireless networks. This paper focuses on the design and evaluation of routing protocols applicable to this class of hierarchical ad-hoc networks. The performance of a hierarchical network with the popular dynamic source routing (DSR) protocol is evaluated and compared with that of a conventional “flat” ad-hoc networks using an ns-2 simulation model. The results for an example sensor network scenario show significant capacity increases with the hierarchical architecture (∼4:1). Alternative routing metrics that account for energy efficiency are also considered briefly, and the effect on user performance and system capacity are given for a specific example.
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paper_title: A practical scheme for non-interactive verifiable secret sharing

paper_content:

This paper presents an extremely efficient, non-interactive protocol for verifiable secret sharing. Verifiable secret sharing (VSS) is a way of bequeathing information to a set of processors such that a quorum of processors is needed to access the information. VSS is a fundamental tool of cryptography and distributed computing. Seemingly difficult problems such as secret bidding, fair voting, leader election, and flipping a fair coin have simple one-round reductions to VSS. There is a constant-round reduction from Byzantine Agreement to non-interactive VSS. Non-interactive VSS provides asynchronous networks with a constant-round simulation of simultaneous broadcast networks whenever even a bare majority of processors are good. VSS is constantly repeated in the simulation of fault-free protocols by faulty systems. As verifiable secret sharing is a bottleneck for so many results, it is essential to find efficient solutions.
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paper_title: Halo: A Hierarchical Identity-Based Public Key Infrastructure for Peer-to-Peer Opportunistic Collaboration

paper_content:

The lack of information security protection for peer-to-peer systems has hampered the use of this robust and scalable technology in sensitive applications. The security weakness is rooted in the server-less architecture and the demand driven ad-hoc operation scenarios of peer-to-peer systems. Together, they prohibit scalable key management using traditional symmetric/ asymmetric cryptographic techniques. The advent of hierarchical identity-based cryptography and thresholded/joint secret sharing offers a possible solution to this problem. In this paper, we present the design of Halo, a hierarchical identity-based public key infrastructure that uses these novel technologies to perform recursive instantiation of private key generators and establish a trust hierarchy with unlimited number of levels. The PKI thus enables the employment of hierarchical identity-based public key encryption, signature, and signcryption for the protection of peer-to-peer applications. The effort to implement a proof-of-concept prototype as a JXTA service module was also discussed.
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paper_title: An ad hoc network with mobile backbones

paper_content:

A mobile ad hoc network (MANET) is usually assumed to be homogeneous, where each mobile node shares the same radio capacity. However, a homogeneous ad hoc network suffers from poor scalability. Recent research has demonstrated its performance bottleneck both theoretically and through simulation experiments and testbed measurement Building a physically hierarchical ad hoc network is a very promising way to achieve good scalability. In this paper, we present a design methodology to build a hierarchical large-scale ad hoc network using different types of radio capabilities at different layers. In such a structure, nodes are first dynamically grouped into multihop clusters. Each group elects a cluster-head to be a backbone node (BN). Then higher-level links are established to connect the BN into a backbone network. Following this method recursively, a multilevel hierarchical network can be established. Three critical issues are addressed in this paper. We first analyze the optimal number of BN for a layer in theory. Then, we propose a new stable clustering scheme to deploy the BN. Finally LANMAR routing is extended to operate the physical hierarchy efficiently. Simulation results using GloMoSim show that our proposed schemes achieve good performance.
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paper_title: Perfectly-Secure Key Distribution for Dynamic Conferences

paper_content:

A key distribution scheme for dynamic conferences is a method by which initially an (off-line) trusted server distributes private individual pieces of information to a set of users. Later any group of users of a given size (a dynamic conference) is able to compute a common secure key. In this paper we study the theory and applications of such perfectly secure systems. In this setting, any group of t users can compute a common key by each user computing using only his private piece of information and the identities of the other t - 1 group users. Keys are secure against coalitions of up to k users, that is, even if k users pool together their pieces they cannot compute anything about a key of any t-size conference comprised of other users.First we consider a non-interactive model where users compute the common key without any interaction. We prove a lower hound on the size of the user's piece of information of (k+t-1 t-1) times the size of the common key. We then establish the optimality of this bound, by describing and analyzing a scheme which exactly meets this limitation (the construction extends the one in [2]). Then, we consider the model where interaction is allowed in the common key computation phase, and show a gap between the models by exhibiting an interactive scheme in which the user's information is only k + t - 1 times the size of the common key. We further show various applications and useful modifications of our basic scheme. Finally, we present its adaptation to network topologies with neighborhood constraints.
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paper_title: Lightweight Sybil Attack Detection in MANETs

paper_content:

Fully self-organized mobile ad hoc networks (MANETs) represent complex distributed systems that may also be part of a huge complex system, such as a complex system-of-systems used for crisis management operations. Due to the complex nature of MANETs and its resource constraint nodes, there has always been a need to develop lightweight security solutions. Since MANETs require a unique, distinct, and persistent identity per node in order for their security protocols to be viable, Sybil attacks pose a serious threat to such networks. A Sybil attacker can either create more than one identity on a single physical device in order to launch a coordinated attack on the network or can switch identities in order to weaken the detection process, thereby promoting lack of accountability in the network. In this research, we propose a lightweight scheme to detect the new identities of Sybil attackers without using centralized trusted third party or any extra hardware, such as directional antennae or a geographical positioning system. Through the help of extensive simulations and real-world testbed experiments, we are able to demonstrate that our proposed scheme detects Sybil identities with good accuracy even in the presence of mobility.
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paper_title: Threshold and identity-based key management and authentication for wireless ad hoc networks

paper_content:

As various applications of wireless ad hoc network have been proposed, security has become one of the big research challenges and is receiving increasing attention. In this paper, we propose a distributed key management and authentication approach by deploying the recently developed concepts of identity-based cryptography and threshold secret sharing. Without any assumption of prefixed trust relationship between nodes, the ad hoc network works in a self-organizing way to provide the key generation and key management service, which effectively solves the problem of single point of failure in the traditional public key infrastructure (PKI)-supported system. The identity-based cryptography mechanism is applied here not only to provide end-to-end authenticity and confidentiality, but also to save network bandwidth and computational power of wireless nodes.
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Title: A Survey on Key Management of Identity-based Schemes in Mobile Ad Hoc Networks

Section 1: PRELIMINARIES
Description 1: Discuss the background knowledge including brief history, basic concepts of IBC, identity-based encryption (IBE) and signature (IBS) schemes, and threshold cryptography.

Section 2: Identity-Based Cryptography
Description 2: Explain the concept of identity-based cryptography, its development, and key functions involved in IBE and IBS schemes.

Section 3: Threshold Cryptography
Description 3: Describe the principle of (t, n) threshold cryptography and its application in identity-based key management schemes.

Section 4: IDENTITY-BASED KEY MANAGEMENT SCHEMES
Description 4: Introduce multiple identity-based key management schemes developed to mitigate the key escrow problem in MANETs.

Section 5: Traditional Threshold Identity-Based Schemes
Description 5: Detail the operation, strengths, and weaknesses of traditional threshold identity-based schemes, including key generation and distribution processes.

Section 6: SSPK Identity-Based Schemes
Description 6: Discuss the SSPK identity-based scheme using Verifiable Secret Sharing (VSS) and how it differs from traditional threshold schemes.

Section 7: Certificateless Schemes
Description 7: Explain certificateless public key cryptography (CL-PKC) schemes, their benefits, and how they overcome the key escrow problem.

Section 8: Hierarchical Identity-Based Schemes
Description 8: Describe hierarchical identity-based schemes, their applications in hierarchical MANETs, and methods for key management in such environments.

Section 9: Techniques to Improve Identity-Based Scheme
Description 9: Summarize various techniques in the literature to enhance the security and availability of key management in identity-based schemes for MANETs.

Section 10: CONCLUSIONS
Description 10: Offer an overview of the findings, comparing various identity-based key management schemes, discussing their strengths and weaknesses, and proposing areas for future research.