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Joint Research on Environmental Science and Technology for the Earth

In the new era of communication and network technologies, a routing protocol not only operates on some lower levels of a network protocol. It also operates on the application layer the highest-level layer in network protocol stack. So we call this is upper layer routing protocol. But it must be based on lower layers to make routing decisions. But normal routing protocols are used for most static network or rather small wireless networks or not high mobility networks. In mobile ad-hoc networks, nodes move very often and fast, so bandwidth of connection between them can be reduced. Therefore the transmission delay may be increased. The paper aims at purpose to increate QOS routing by hierarchical clustering routing by using R+ tree in addition with some advanced techniques multicast routing, multiple paths, use GEN/ BEE/ ANT to optimize routes to transmit data.

MANET (Mobile Ad-Hoc Network) is autonomous system, not based on existing infrastructure. Nodes usually change their position, network topology changes very fast. Service Based Routing is inherited from the model of Content Based Routing - CBR that manages and classifies many of network services. In order making nodes to communicate quickly and stablely, it requires applying some methodologies to reduce overhead and delay as well as power consumption. Therefore, this paper mentions a hierarchical clustered based routing using R^+Tree. R^+ is a data structure with fast algorithms to establish, insert, update. It has been used in many fields effectively and efficiently such as Google Map, Forwarding technique, computer virtual memory. In combination with some artificial intelligence algorithms to make cluster, find optimized routes, multicast trees for effective communication. Fuzzy logic and genetic al. are proved to be very compatible with Manet. A genetic algorithm is used to choose optimized clusters, Fuzzy logic is applied to choose the cluster head and members of each cluster. Multiple paths routing is very importance for routing in MANET that making Quality of Service by Ant Colony Optimization Algorithm.

In service based routing (SBR) [5], the problem for storing forwarding table that includes searching predicates received from subscribers through subscription messages is an important job. When a content request happens, the subscriber will create a subscription message. The subscription message stores several kinds of information, the most important content is a filter that is a conjunction of some constraints [5]. A filter is denoted by F character, that has mathematical formula: F = ⋀n i=1C1, in which C1 is service request, has the format: C1= ‘Service_name = requested service name’. Every C1 (i=¯(2..n)) is a constraint that is formed by three components: (Key, op, Value), Key is a keyword for searching, op is an operator, Value is searching condition. Key belongs to the set of name of properties of content messages that the requested service supplies. Op is an operator that depends on the type of data of the Key. Therefore the forwarding table is a set of filters which are received from all subscribers on networks. The algorithms for inserting, updating, deleting and finding filters that match content messages have been published by service providers are very important. In this paper, We mention a technique for forwarding technique on the basic of summary filter for storing and searching filter quickly. This technique is based on some previous researches. In section 8, give an algorithm for finding all network nodes that have matched filters with a content message. Section 7 introduces a cluster routing technique based on summary filter.

In Cryptography, there are two kinds of methods for encryption and decryption. They are symmetric cryptography and asymmetric cryptography. In symmetric cryptography, it uses a single key for encryption and decryption. In asymmetric cryptography, it uses both public key and private key for encryption and decryption. In MANET (mobile ad-hoc network) every node usually moves and has limited energy, so network link is not stable and has low bandwidth. Therefore it is very carefully to choose the cryptography for ad-hoc network or MANET. If the transaction is very important, for example online banking, can use an asymmetric algorithm. So Elliptic Curve Cryptography is right choice. For data and control traffic, the symmetric cryptography can be the good selection, especially stream ciphers are very comfortable. We use Elliptic Curve Cryptography (ECC) with its arithmetic operations on finite fields to build public - key cryptographic schemes consisting of: i) signature schemes; ii) encryption schemes; and iii) key agreement schemes. In key management, public key cryptography is used to distribute the secret keys used in other cryptographic algorithms (for example DES). For digital signatures, public key cryptography is used to authenticate the origin of data and protect the integrity of that data. Early public key systems are secure based on difficulty of factoring a large integer composed by two or more large prime integers. With Elliptic Curve based protocol, its security is based on assuming that is difficult to find the discrete logarithm of a random point on Elliptic Curve with respect to a publicly known base point. The size of EC determines the level of difficulty of the problem. If comparing to RSA, with the same level of security, RSA has to use larger public key, for example ECC of 256 bits public key is with the same level of security as 3072 bits public key RSA. To use RSA or Diffie-Hellman to protect 128-bit AES keys one should use 3072-bit parameters: three times the size in use throughout the Internet today. The equivalent key size for elliptic curves is only 256 bits.

Mobile Ad-hoc Network (Manet) consists of a set of network nodes which change, not based on an existing network infrastructure as well as the centralized control. Network nodes usually have limited energy, bandwidth limitations, so find a way to transfer packets in the network is very important. To minimize packet loss, efficient bandwidth utilization at the node requires routing protocol must be compact, efficient, accurate. Fuzzy logic is a logical field studies evaluating the accuracy of the results based on the approximation of the components involved, make decisions based on many factors relative accuracy based on experimental or mathematical proof. Each component of the logical expression is usually belong to one set of defined unclear (fuzzy set). In this paper, We give some researchs applied fuzzy logic in assessing the network routing and bandwidth management on the basis of a number of existing studies.

In Service Based Routing (SBR), data is transmitted from a source node to destination nodes are not depended on destination addresses. Hence, it is comfortable with new advanced technology as cloud computing and also flexible and reliable. Genetic and Queen-Bee algorithms (GA, QB) are artificial intelligence techniques for combinatorial optimization problems solving based on some natural rules. In which GA is a branch of the evolutionary strategies that uses some principles of evolution theory, such as natural selection, mutation and crossover. QB is performed based on GA for energy saving. The R^+ tree is an effective data structure that can be used to organize a hierarchical clustering network with fast establishing, updating, tuning algorithms. The usage of the Greedy algorithm to find cyclic routes or multiple paths on each trunk by multiple criterions to transmit data effectively.

In the advanced routing of new networks communication and network technologies, it not only operates on some lower levels of a network protocol. But it also operates on some upper layers such as the application layer the highest-level layer in network protocol stack of OSI model. The routing process can be known by a more abstract concept. It can process on many layers on network’s stack of OSI model. So this kind of routing may be called the upper layer routing protocol. As the content based routing, in the service based routing protocol, the information can be classified by categories or service classes. Subscribers and publishers can communicate with each other but they don’t know other’s address. So it is more dynamical in processing and more comfortable for ad-hoc network. However the upper routing must be based on lower layers to make routing decisions. But normal routing protocols are used for most static network or rather small wireless networks or not high mobility networks. In mobile ad-hoc networks, nodes move very often and fast, so bandwidth of connection between them may be reduced. Therefore the transmission delay may be increased. The paper aims at purpose to increate QOS of routing by hierarchical clustering routing by using R+ tree in addition with some advanced techniques multicast routing, multiple paths, use GEN/ BEE/ ANT to optimize routes to transmit data. In R+ tree model, the network’s nodes are managed by Bottom-Up model from leaf nodes to root of the tree. All the leaf nodes, inner nodes and root of this tree are used for two roles: i) Manage a cluster that consists all nodes that have direct connections with this node; ii) Operate as a normal node. The paper mentions: (i) Setup hierarchical clustering network by using R tree structure. (ii) Making multicast tree from some cluster heads for fast routing. (iii) Making optimized route by Ant Colony Optimization.

In advance network we may use service Based Routing (SBR), so data is transmitted from a source node to destination nodes are not depended on destination addresses. So, it may be comfortable with new advanced technology as cloud computing and also flexible and reliable. Multicast routing is advanced technique to deliver data simultaneously from one source node to multiple destination nodes with QOS (quality of service). In this paper, we introduce a technique that is extended from multicast technique with multiple multicast trees that are conformed quality of service routing and multiple path routing. It also guarantees QOS of routes such as bandwidth. This technique is based on Greedy, Ant Colony Optimization, artificial neural network and fuzzy logic to get optimal routes to transmit data from one source to multiple destination node very effectively. The usage of the ANT Colony optimization, Greedy, fuzzy logic algorithms to find cyclic or multiple paths routes on each trunk by multiple criterions to transmit data effectively.

MANET (short for Mobile Ad-Hoc Network) consists of a set of mobile network nodes, network configuration changes very fast. Each node will act as a router to maintain network operation. As some standard content based routing protocols, when a node publishes its content, it will broadcast data to network. The published content will be cached at all routers on the network. So when a node publish a request to get some content, it will prepare a subscription message then broadcast it. When any node on network received that subscription, it matches subscription’s content with published content that have been cached on it. If found then matched content will be transferred to requested node. Service Oriented Routing is inherited from the model of content based routing (CBR), combined with several advanced techniques such as Multicast, Genetic algorithm (GA) increase the data rate, and data encryption to ensure information security.

We present a new method to calculate the required bandwidth for ATM connections. We first develop analytical models for bandwidth allocation of constant bit rate (CBR) and variable bit rate (VBR) services based on the declared usage parameter control (UPC) parameters. Based on the analytical models, we derive the closed form expressions of the required bandwidth for both service classes. Numerical analysis is given and it shows a close relationship between the quality of service (QoS) parameters (cell loss and delay parameters) and network's resource (link capacity and buffer size). The closed form expressions can be used for simple but efficient bandwidth allocation scheme of call admission control (CAC) function.