KR20090079552A - Method for Route Optimization for Network Mobility in Heterogeneous Networks - Google Patents

Abstract

A method for optimizing a route according to network mobility in a heterogeneous mobile network are provided to reduce total end-to-end packet delay by transmitting a packet to a corresponding node promptly without passing an HA(Home Address) of a mobile router. A first mobile network performs a delegation request protocol for updating binding and optimizing a route during moving to a first external link from a home link(S101). When the first mobile network is moved to a first external link, the first mobile network updates the binding by using a second mobile network and an optimization protocol(S109). The second mobile network performs the delegation request protocol(S111). An optimized route between the first and second mobile network is generated by using binding update information(S113).

Description

Route optimization method according to network mobility in heterogeneous mobile networks {Method for Route Optimization for Network Mobility in Heterogeneous Networks}

The present invention relates to a path optimization method according to network mobility in a heterogeneous mobile network.

With the proliferation of mobile terminals such as laptops, PDAs, and mobile phones and the need for all-IP networks such as 4G cellular networks, the development of IP-based mobility support technology that is independent of infrastructure In order to provide mobile terminal users with an unprecedented level of quality of service (QoS) for Internet access and use, path optimization (ie, binding update) is essential.

Currently, research on network mobility is focused on the Network Mobility (NEMO) working group of the Internet Engineering Task Force (IETF). However, the current standardization work on NEMO is only proposed by Devarapalli and three others in 2005 as the Request for Comment (RFC) 3963. In addition, a total of nine Internet drafts have been submitted, including NEMO support objectives and requirements and NEMO support terminology.

In the study of NEMO based on mobile IPv6 (MIPv6), TAHI project, which is combined with Japan University of Tokyo, YDA company, and Yokogawa Electric company, is currently underway. The project aims to provide and develop verification technology for IPv6.

In Korea, SNU, ICU, and many universities are conducting research on efficient route optimization methods for NEMO. In addition, research on NEMO is being conducted at state-run research institutes including Samsung ETRI and Samsung Botanical Garden, but it is still insufficient. Especially, the development and product launch of NEMO is only in the beginning stage of domestic and overseas companies.

In NEMO, when an arbitrary network is moved and the access point in the Internet is changed, the terminal in the network should be able to access the Internet without changing its address regardless of the movement. In addition, even when the terminal in the network is communicating with any corresponding node on the Internet, the communication between the terminal and the corresponding node must be maintained without disconnection.

Basically, all services currently available through the Internet can be provided to all terminals in the mobile network. For example, users with laptops, PDAs, PSPs, or PDPs can use Internet services over wired / wireless LANs in transportation such as trains, buses, airplanes, and ships. In addition, mobility services for cars are possible.

On the other hand, in terms of security, NEMO support is performed wirelessly in an IPv6 environment, making it easy for an attacker to tamper with contents as well as eavesdropping data transmitted between users. Therefore, if this process is not authenticated, the attack damage is larger than the existing MIPv6. This is because all network nodes that use the prefix that the attacker is eavesdropping on are forgery of the transmitted data. In other words, in NEMO, the attack damage is large because one router can perform the path optimization process on behalf of all the terminals in the mobile network. Therefore, in order to be robust against attacks that can occur in MIPv6 and to counter attacks that can occur in NEMO environment, the following security requirements must be satisfied.

The Authentication of Requester: The node receiving the binding update message MUST be able to authenticate the requestor.

2. The Authentication of Recipient: The requestor requesting a binding update must be able to authenticate the responder.

3. The Integrity of Binding Update Information: The binding update information must be protected from other attackers.

4. The Authentication of the Requester's Location: The Responder must be able to verify that the requester is present at the current location.

 In the past, protocols have been proposed to improve this problem. First, Maria Calderon and three others presented a more efficient path optimization process between the mobile node and the corresponding node by analyzing the path optimization process in a non-overlapping NEMO environment and delegating the binding update authority of the mobile network node to the mobile router. Since the mobile network node handles this process by delegating authority for binding renewal to the mobile router, the overall overhead is reduced.

1 is a diagram illustrating a network mobility operation process in a general mobile network. In FIG. 1, a mobile network consists of one or more mobile routers (MRs) and mobile nodes (MNNs).

When the mobile network is on the home link, the mobile router (MR) assigns a home address (HoA) to the HA, and the mobile node (MNN) communicates with the corresponding node (CN) via the mobile router (MR). do. At this time, when the mobile network leaves the home link and moves to the external link, the mobile router MR receives a care of address (CoA) from the access router AR and registers with the HA. In this way, bidirectional tunneling is formed between the mobile router and the HA, and the mobile node MNN and the corresponding node CN communicate with each other.

As shown in FIG. 1, when the mobile network moves from the home link to the external link, the MR must register a care-of address (CoA) obtained at the current location with its HA. Otherwise, various mobile nodes (MNNs) in the mobile network may be disconnected and may not receive Internet services, and may not be able to communicate with corresponding nodes (CNs). In addition, in the NEMO basic support protocol, the MR registers a care-of address (CoA) acquired only for its HA, which causes pinball path problems in the overlapping network as well as the triangular path problem.

The present invention has been made to solve the above problems, and an object thereof is to provide an authenticated path optimization method that enables more stable and efficient communication in heterogeneous mobile networks.

In order to achieve the above object, the present invention provides a first mobile network comprising a first mobile router and first mobile nodes, and a second mobile router as a heterogeneous mobile network. In the heterogeneous mobile network network path optimization method comprising a second mobile network consisting of corresponding nodes, while the first mobile network is moving from the home link to the first external link, the first mobile network is updated binding; And a first step of performing an authorization delegation request protocol for performing path optimization, and when the first mobile network moves to the first external link, the first mobile network updates the binding using the second mobile network and the optimization protocol. The second step and the second mobile network request authorization delegation to perform binding update and path optimization. A third step of performing a protocol, and a fourth step of generating an optimization path between the first mobile network and the second mobile network using the binding update information.

The optimization protocol includes step a of generating a public key and a private key of each mobile router, step b of generating a partial session key using each generated private key, and using the generated partial session key. C may be generated to generate a final session key.

In step a, each mobile router transmits its identity information to each public key generator, and the received public key generator generates a private key using its own public key. The public key of the router may be signed to issue the private key of the mobile router, and may be transmitted to each mobile router. In step b, each mobile router may generate a partial session key using the received private key.

In the first step, the authority delegation request protocol is a step in which the first mobile router requests authority delegation to the first mobile node, and the first mobile node receiving the authority delegation request grants authority delegation to the first mobile router. Can be done.

In the third step, the authority delegation request protocol may be performed by the second mobile router requesting authority delegation from the corresponding node, and the corresponding node receiving the authority delegation request may authorize the authority delegation to the second mobile router.

According to the present invention, by providing an optimized path in a heterogeneous mobile network, it is possible to communicate more stably and efficiently.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals have the same reference numerals as much as possible even if displayed on different drawings. In describing the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

2 is a diagram illustrating a path optimization process according to network mobility in a heterogeneous mobile network according to an embodiment of the present invention.

In FIG. 2, the first mobile network 100 is composed of a first mobile router 110 and a first mobile node 120. The second mobile network 200 is configured as a heterogeneous mobile network with the first mobile network 100 and corresponding nodes 220 communicating with the second mobile router 210 and the first mobile node 120. 2 illustrates an example in which communication is performed between MNN1 among the first mobile nodes 120 and CN2 among the corresponding nodes 220.

When the first mobile network 100 is on the home link, communication between the first mobile node (MNN1) 120 and the corresponding node (CN2) 220 occurs through the original packet path as shown in FIG. That is, the first mobile node MNN1 120, the first mobile router MR1, the first AP 300, the first HA 500, the second HA 600, the second AP 400, and the second mobile router ( Two-way communication takes place in the order of MR2), the corresponding node (CN2) 220, or vice versa.

The first mobile network 100 moves from the home link to the first external link (S101).

While the first mobile network 100 moves to the first external link, the first mobile network 100 performs an authority delegation request protocol for performing binding update and path optimization (S103). More specifically, the first mobile network 100 is received from the home link by comparing the radio wave strength of the prefix message received from the various routers present in the home link and the first external link while moving to the first external link. When the propagation strength of the advertisement message is weak, the first mobile router 110 determines that the mobile station 110 is moving to an external link. Thereafter, the first mobile router 110 goes through the authority delegation request protocol procedure with the mobile node 120 in the first mobile network 100. Furthermore, after performing the authority delegation protocol procedure, the first mobile router 110 generates a care-of address (CoA) through an address autoconfiguration scheme using a message having the strongest propagation strength of the prefix message received from the external link.

A binding update using a bidirectional tunnel is performed between the first mobile router MR1 of the first mobile network 100 and the first HA 500 (S105). Through this, a new bypass route using the first HA 500 and the second HA 600 is generated (S107).

When the first mobile network 100 moves to the first external link, the first mobile network 100 updates the binding by using the optimization protocol with the second mobile network 200 (S109).

The second mobile network 200 performs an authority delegation request protocol for performing binding update and path optimization (S111).

The optimization path between the first mobile network 100 and the second mobile network 200 is generated using the binding update information in step S109 (S113). That is, as shown in Figure 2, a new direct path is created.

In the present invention, the optimization protocol includes step a of generating a public key and a private key of each mobile router, step b of generating a partial session key using each generated private key, and using the generated partial session key. In step c, a final session key is generated.

In this case, in step a, each mobile router transmits its identity information to each public key generator, and the received public key generator generates a private key using its own public key. The public key of the router is signed to issue a private key of the mobile router, and the mobile key is transmitted to each mobile router. In this case, each mobile router generates a partial session key using the received private key.

In an embodiment of the present invention, in step S103, the authority delegation request protocol may include requesting authority delegation from the first mobile router (MR1) 110 to the first mobile node (MNN1) 120, and receiving the authority delegation request. The first mobile node (MNN1) 120 may be configured to approve delegation of authority to the first mobile router (MR1) 110. In the present invention, the authority delegation request protocol is performed through the IPsec ESP tunnel to securely delegate authority.

In an embodiment of the present invention, in step S111, the authority delegation request protocol may include requesting authority delegation from the second mobile router (MR2) 210 to the corresponding node (CN2) 220, and corresponding node receiving the authority delegation request. (CN2) 220 may be a step of approving delegation of authority to the second mobile router (MR2) (210). In the present invention, the authority delegation request protocol is performed through the IPsec ESP tunnel to securely delegate authority.

Examining the stability of the entire protocol in the NEMO of the present invention is as follows. We will look at the NEMO security requirements for authentication of the requestor, authentication of the responder, integrity of update information, and authentication of address ownership.

First, in the authentication portion for the requester, the corresponding node CN should check whether the mobile router MR has a delegation authority to the mobile node MNN before accepting the binding update request of the mobile router MR. In the protocol of the present invention, the correspondent node CN compares the home address of the mobile node MNN added to the home address option of the message received from the mobile router MR with the home address stored in its binding cache. Through this process, the correspondent node CN may determine that the mobile router MR is a legitimate node having a delegation authority to perform binding update from the mobile node MNN.

The authentication part for the responder, in turn, must verify that the mobile router MR is a legitimate user and that the correspondent node CN has sent a binding update message. To this end, the mobile router MR checks the signature of the binding update message with the public key of the corresponding node CN. The mobile router MR thus authenticates the responder by using the public key of the correspondent node CN to prove address ownership.

The integrity portion of the update information must provide the integrity of its information and messages as claimed by the mobile router MR in the binding update request. If this is not provided, the attacker can forge multiple attacks by forging binding update messages. In the protocol of the present invention, since the entire message is signed with its private key, it is not easy to find the private key of a legitimate user without manual encryption analysis.

Finally, the address ownership authentication part must verify that the corresponding node CN verifies that the care-of address CoA obtained by the mobile router MR on the external link is actually the address of the mobile router MR. In the present invention, a malicious node including an attacker can generate an arbitrary referral address at any time, but since it is difficult to know the private key corresponding to the public key included in the address, ownership of the address currently being used by another node is lost. I can't argue.

In the present invention, end-to-end packet transmission delay time is analyzed as follows. 3 is a diagram illustrating a packet transmission path in a conventional mobile network. 4 is a diagram illustrating a packet transmission path in a mobile network according to an embodiment of the present invention.

In FIG. 3, the packet is delivered through MNN1, MR1, AP, HA _MR1 , HA _MR2 , AP, MR2, and CN2. In FIG. 4, the packet is delivered through MNN1, MR1, AP, AP, MR2, and CN2.

Compared to FIG. 3 and FIG. 4, the conventional mobile network uses a bidirectional tunnel between MNN1 and MR1. However, in the present invention, the entire end-to-end packet delay time is reduced because it is directly transmitted to CN2 without passing through HA of MR1.

While the invention has been described using some preferred embodiments, these embodiments are illustrative and not restrictive. Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention and the scope of rights set forth in the appended claims.

1 is a diagram illustrating a network mobility operation process in a general mobile network.

2 is a diagram illustrating a path optimization process according to network mobility in a heterogeneous mobile network according to an embodiment of the present invention.

3 is a diagram illustrating a packet transmission path in a conventional mobile network.

4 is a diagram illustrating a packet transmission path in a mobile network according to an embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

100 First Mobile Network 200 Second Mobile Network

300 First AP 400 Second AP

500 1HA 600 2HA

700 Internet 110 First Mobile Router

120 First Mobile Node 210 Second Mobile Router

220 correspondence node

Claims (6)

A first mobile network consisting of a first mobile router and first mobile nodes, and a second mobile network comprising a second mobile router and corresponding nodes communicating with the first mobile node as a heterogeneous mobile network; In the network movement path optimization method in a heterogeneous mobile network comprising a, While the first mobile network is moving from the home link to the first external link, the first mobile network performs a delegation request protocol for performing binding update and route optimization; When the first mobile network moves to the first external link, the first mobile network updates the binding using the second mobile network and the optimization protocol; The second mobile network performs a third step of performing a delegation request protocol for performing binding updating and path optimization; A fourth step of generating an optimization path between a first mobile network and a second mobile network by using the binding update information; Path optimization method according to network mobility in a heterogeneous mobile network comprising a. The method of claim 1, The optimization protocol includes step a of generating a public key and a private key of each mobile router, step b of generating a partial session key using each generated private key, and using the generated partial session key. Path optimization method according to network mobility in a heterogeneous mobile network, characterized in that the step of generating a final session key. The method of claim 2, In step a, each mobile router transmits its own identity information to each public key generator, and the received public key generator generates a private key using its own public key. A route optimization method according to network mobility in a heterogeneous mobile network, characterized by issuing a private key of a mobile router by signing a router's public key and transmitting it to each mobile router. The method of claim 3, In step b, each mobile router generates a partial session key by using the received private key. Path optimization method according to network mobility in a heterogeneous mobile network. The method according to any one of claims 1 to 4, In the first step, the authority delegation request protocol includes the steps of requesting authority delegation to the first mobile node by the first mobile router and approving authority delegation to the first mobile router by the first mobile node which has received the authority delegation request. Path optimization method according to network mobility in a heterogeneous mobile network, characterized in that consisting of. The method according to any one of claims 1 to 4, In the third step, the authority delegation request protocol includes a step in which the second mobile router requests authority delegation to the corresponding node, and the corresponding node receiving the authority delegation request approves authority delegation to the second mobile router. Path optimization method according to network mobility in heterogeneous mobile networks.

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