• Proceedings of the Korean Information Science Society Conference
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• 2003.04d
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• pp.581-583
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• 2003

현재 인터넷에서는 사용자의 급격만 증가로 인해 고성능의 라우터를 요구하고 있고 주소부족으로 IPv4에서 IPv6로 변화를 하고 있다. IPv4처럼 IPv6에서도 Address Lookup이 병목이 될 것이며 IPv4와는 달리 IPv6는 128bit의 주소 길이를 가지고 있어 이에 맞는 라우터 구조와 Address Lookup 알고리즘이 필요하다. 본 논문에서는 IPv6주소 128bit 중 외부에서 할당받는 64bit를 3단계로 나누는 계층적 네트워크 구성과 각 단계에 적합한 라우팅 테이블 구조와 Address Lookup 알고리즘에 대해 연구하였고 펜티엄 III 866MHz의 프로세서에서 알고리즘의 검색 시간을 측정해 각 단계에 맞는 라우팅 테이블 구조를 제안하였다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.1
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• pp.88-97
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• 2000

We have proposed and analysed a novel Lookup Algorithm which had a short switching speed and tiny memory size for IP router. This algorithm could simply be implemeted by a hardware with SRAM because of simple structure. This Lookup scheme needs 1${\sim}$3 memory access times. When we simulated with 40,000 routing record obtained from IPMA Website, the maximum memory size of this algorithm was 316KB(the offset threshold for compression algorithm was 8). When we simulated by HDL using ALTERA EPM7256 series and 100MHz clock and SRAM of 10ns access time, the total lookup time was 45ns for two memory access, 175ns for three memory access.

• The KIPS Transactions:PartA
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• v.11A no.5
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• pp.333-340
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• 2004

In order that routers forward a packet to its destination, they perform IP address lookup which determines the next hop according to the packet's destination address. In designing high speed routers, IP address lookup is an important issue. In order to design high speed routers, this paper proposes a parallel IP lookup scheme which consists of several IP lookup engines without any modification of already fabricated indirect IP lookup chipsets. Also, we propose a simple rule for partitioning IP prefix entries In an overall forwarding table among several IP lookup engines. And we evaluate the performance of the proposed scheme in terms of the memory size required for storing lookup information and the number of memory accesses on constructing the forwarding table. With additional hardware logics, the proposed scheme can reduce about 30% of the required memory size and 80% of the memory access counts.

• Proceedings of the IEEK Conference
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• 2000.11a
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• pp.213-216
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• 2000

In this paper, we propose a new scheme which improves the IP address lookup time. The new scheme is composed of two core technologies, named the prefix alignment and the prefix distance ordering. Now, as the Internet is being used commonly by improving the data transmission capacity, the need for enlarging the bandwidth of the Internet is on the rise. IP address lookup performance problem is an important obstacle in the router executing high speed packet forwarding. This results from the fact that the prefixes routing table is composed of and the traffic being processed in unit time are largely on the increase. The proposed lookup scheme is divided into two parts in technology, the one is the algorithm forming a routing database(routing table), the other is the lookup procedure in the actual packet processing.

• Journal of Communications and Networks
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• v.3 no.4
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• pp.374-382
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• 2001

Nowadays, the commonly used table lookup scheme for IP routing is based on the sc-called classless interdomain routing (CIDR). With CIDR, routers must find out the best matching prefix (BMP) for IP packets forwarding, this complicates the IP lookup. Currently, this process is mainly performed in software and several schemes hale been proposed for hardware implementation. Since the IP lookup performance is a major design issue for the new generation routers, in this article we investigate the properties of the routing table and present a new approach for IP lookups, our approach is not based Gn BMP and significantly reduces the complexity, thus the computation cast of existing schemes can be significantly reduced. We also propose an efficient IP lookup algorithm, with which we improve the binary search on prefixes to 30 millions of packets per second (MPPS) and 5,000 route updates/s under the same experiment setup with an even larger routing table.

• International journal of advanced smart convergence
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• v.5 no.3
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• pp.47-55
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• 2016

Router main task is to provide routing of Internet Protocol (IP) packets. Routing is achieved with help of the IP lookup. Router stores information about the networks and interfaces in data structures commonly called as routing tables. Comparison of IP from incoming packet with the IPs stored in routing table for the information about route is IP Lookup. IP lookup performs by longest IP prefix matching. The performance of the IP router is based on the speed of prefix matching. IP lookup is a major bottle neck in the performance of Router. Various algorithms and data structures are available for IP lookup. This paper is about reviewing various tree based structure and its performance evaluation.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.5
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• pp.345-353
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• 2003

When designing network processors or implementing network equipments such as routers are implemented, IP lookup operations cause the major impact on their performance. As the organization of the IP address becomes simpler, the speed of the IP lookup operations can go faster. However, since the efficient management of IP address is inevitable due to the increasing number of network users, the address organization should become more complex. Therefore, for both IPv4(IP version 4) and IPv6(IP version 6), it is the essential fact that IP lookup operations are difficult and tedious. Lots of researcher for improving the performance of IP lookups have been presented, but the good solution has not been came out. Software approach alleviates the memory usage, but at the same time it si slow in terms of searching speed when performing an IP lookup. Hardware approach, on the other hand, is fast, however, it has disadvantages of producing hardware overheads and high memory usage. In this paper, conventional researches on IP lookups are shown and their advantages and disadvantages are explained. In addition, by mixing two representative structures, a new hybrid parallel architecture for fast IP lookups is proposed. The performance evaluation result shows that the proposed architecture provides better performance and lesser memory usage.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.2B
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• pp.138-143
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• 2003

One of the important design issues for IP routers responsible for packet forwarding in computer networks is the route-lookup mechanism. For each incoming packet, IP routing requires that a router performs a longest-prefix-match address lookup in order to determine the next hop that the incoming packet should be forwarded to. In this paper, we present a new scheme which applies the hashing function for IP address lookup. In the proposed scheme, the forwarding table is composed of multiple SRAMs, and each SRAM represents an address lookup table in each prefix. Hashing function is applied in order to find out the matching entries from the address lookup tables in parallel, and the entry with the longest prefix match among them is selected. Simulation using the MAE-WEST router example shows that a large routing table with 37000 entries can be compacted to a forwarding table of 300 Kbytes in the proposed scheme. It is also shown that the proposed scheme achieves one route lookup every 1.93 memory accesses in average.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.4B
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• pp.298-305
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• 2003

In this paper, we proposed a high performance lookup controller for IP packet forwarding engine of ATM based label edge routers. The lookup controller is designed to provide services such as MPLS, VPN, ELL, and RT services as well as the best effort. For high speed searching for IP addresses, we employed a TCAM based hardware search device not using traditional algorithmic approaches. We also implement lookup control functions into FPGA for fast processing of packet header and lookup control. The proposed lookup controller is designed to support differenciated services for users and to process in pipelined mechanism for performance improvement. A two-step search scheme is also applied to perform lookup for the key combined with multi-field of packet header. We found that the proposed lookup controller provides the performance of about 16M packets per second through simulations.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.5
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• pp.2203-2217
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• 2016

To prevent structured peer to peer (P2P) overlay networksfrom being attacked by malicious nodes, a symmetric lookup-based routing algorithm referred to as Symmetric-Chord is proposed in this paper. The proposed algorithm determines the precision of routing lookup by constructing multiple paths to the destination. The selective routing algorithm is used to acquire information on the neighbors of the root. Authenticity of the root is validated via consistency shown between the information ascertained from the neighbors and information from the yet-to-be-verified root, resulting in greater efficiency of resource lookup. Simulation results demonstrate that Symmetric-Chordhas the capability of detecting malicious nodes both accurately and efficiently, so as to identify which root holds the correct key, and provides an effective approach to the routing security for the P2P overlay network.