MANET Working Group Y.F. Zhang Internet Draft China Mobile Intended status: Informational JW. Wang Expires: Feb. 5, 2009 Tsinghua University D.P. Liu China Mobile July 5, 2008 Cellular-based Central Control (CCC) Mechanism for Mobile Ad hoc Networks draft-zhang-manet-ccc-00.txt Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html This Internet-Draft will expire on Feb 5, 2009. Copyright Notice Copyright (C) The IETF Trust (2008). Abstract Y.F. Zhang, et al. Expires Feb. 5,2009 [Page 1] Internet-Draft CCC for MANET July 2008 This document discusses a cellular based central control mechanism(CCC) for middle/small scale mobile Ad hoc networks. The proposed mechanism can be used for the mobile operators to build a central-controlled and manageable mobile Ad hoc network. Table of Contents 1. Introduction................................................2 1.1. Terminology............................................3 2. Scenarios of MANET in Mobile Operator's Network..............3 3. System architecture.........................................3 3.1. System overview.........................................4 3.1.1. Control Network....................................4 3.1.2. Transport Networks.................................5 4. Control Network.............................................6 4.1. Overview...............................................6 4.2. MANET node configuration................................6 4.2.1. MANET node IP address configuration................6 4.2.2. MANET node routing table construction..............7 4.3. Maintenance of the MANET................................7 4.4. Demolition of the MANET.................................8 4.5. Establishment of Multicast MANET........................8 4.6. Session Control.........................................8 4.7. Control Sequences of the Formation of a Connection.......8 5. Details of the Control Network...............................9 5.1. Client and Server.......................................9 5.2. Structure of Control Message in Terminal and Relay Nodes.9 5.2.1. Structure of Control Message in Terminal Nodes......9 5.2.2. Structure of Control Message in Relay Nodes........10 5.3. Interface between Control Network & Transportation Network11 5.4 Interface between Control network and APP...............11 6. Security Considerations.....................................12 7. IANA Considerations........................................12 8. Conclusions................................................12 9. Acknowledgments............................................12 10. References................................................13 10.1. Normative References..................................13 10.2. Informative References................................13 Author's Addresses............................................13 Intellectual Property Statement................................13 Disclaimer of Validity........................................14 1. Introduction Currently, mobile Ad hoc network (MANET) is more and more popularly used in many civil scenarios. MANET has its advantages in that it does not need any network infrastructure and can be deployed fast. But the lack of control and management mechanism of MANET obstructs Y.F Zhang, et al. Expires Feb. 5, 2009 [Page 2] Internet-Draft CCC for MANET July 2008 mobile operators to widely deploy MANET. In this document, we explore CCC, a cellular based central control mechanism to make MANET controllable and manageable by mobile operators to some extent. The proposed mechanism includes IP address configuration, routing table construction and QoS control of MANET. 1.1. Terminology In this document, the key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" are to be interpreted as described RFC 2119 [1]. This section defines some key concepts using in this document. AP: Access Point. CID: Control Identification. PCT: Power Consumption Table. TDT: Time Delay Table. CCC: Cellular-Based Control. 2. Scenarios of MANET in Mobile Operator's Network The typical scenario to deploy MANET in Mobile operator's network is a middle/small scale MANET applications (e.g. including some tens of Ad hoc nodes) used by multi-mode mobile terminals (including current operating mobile system GSM/3G and Ad hoc network). The reasons why the scale is limited to a middle/small are as follows: First, the operator views MANET as the supplement and of stretch of reach. So it is suitable to keep a middle/small scale for the MANET in mobile operator's network. Second, the operator can control the MANET more easily by current centralized cellular system with a middle/small scale. The tasks may include IP address allocation, node management, MANET topology probe and control and session management. Last, the operator can easily execute charging and billing centrally in a MANET of such scale. 3. System architecture This section describes the system architecture of the cellular based MANET. Y.F Zhang, et al. Expires Feb. 5, 2009 [Page 3] Internet-Draft CCC for MANET July 2008 3.1. System overview The proposed mechanism requires that the MANET node work in dual mode. For example, a cell phone which has a 900/1800MHz GSM network interface and a 2.4GHz IEEE 802.11 interface [2] can be used in the above scenario. We use this GSM/802.11 dual mode cell phone as the example in the following discussion. The GSM/3G network interface of the MANET node enables it to access to the mobile operator's network which controls and manages the MANET. We call this GSM/3G network control network. And the 802.11 network that forms ad hoc connections is called transport network. The function of control network includes: IP address allocation, node management, MANET topology probe and control, session management as well as charging and billing. We shall discuss the charging and billing mechanisms in the future draft.The transport network provides civil MANET services, such as text transportation, audio transportation and video transportation. In the following sections the architecture and the functions of these two kinds of networks a explored and we take GSM as the control network. 3.1.1. Control Network The following picture demonstrates the architecture of the control network. Y.F Zhang, et al. Expires Feb. 5, 2009 [Page 4] Internet-Draft CCC for MANET July 2008 +------------------------------------------------+ | | | +-----------+ +-----------+ | | |Cellphone1 | |Cellphone2 | | | +-----------+ +-----------+ | | \ GSM link / | | \ / | | +--------------+ | | |Control Server| | | +--------------+ | | / \ | | / \ | | +-----------+ +-----------+ | | |Cellphone3 | |Cellphone4 | | | +-----------+ +-----------+ | | | | | | | +------------------------------------------------+ Figure 1: Control Network Architecture MANET nodes connect to the control server using GSM link. The control server is located in the mobile operator's network and it takes the responsibility of IP address allocation and configuration of the MANET node. Meanwhile the MANET nodes send their transport network's link status to the control server which uses this link status information to form a routing path that can satisfy the QoS requirement of the user. The control serve also calculates and forming routing table for each MANET node and send the routing table to the MANET node using GSM link. Session Control can also be executed by this control network. 3.1.2. Transport Networks The MANET nodes use their 802.11 wireless interfaces to form ad hoc transport connections with each other. The transport network is used for application data such as text file, audio and video transportation. In our scenario there are two kinds of routing tables, primary routing table and secondary routing table. For the convenience of management, different form conventional ad hoc network, the primary routing tables of the MANET nodes is received from the control server. The MANET nodes also maintain ad hoc routing table as the secondary routing table from ad hoc routing protocol (such as AODV) which can be used in the case of GSM link failure. The following figure is an example of the transport network. Y.F Zhang, et al. Expires Feb. 5, 2009 [Page 5] Internet-Draft CCC for MANET July 2008 +------------------------------------------------+ | | | +-----------+ +-----------+ | | |Cellphone1 | |Cellphone2 | | | +-----------+ +-----------+ | | \ / | | \ / | | +------------+ / | | |Cellphone3 | / | | +------------+ / | | / \ / | | / \ / | | +-----------+ +-----------+ | | |Cellphone4 | |Cellphone5 | | | +-----------+ +-----------+ | | | | | | | +------------------------------------------------+ Figure 2: Transport Network Architecture 4. Control Network The transport network is same as the typical MANET. In this section we focus on the control network functions[3]. 4.1. Overview Every MANET node has a Control Identification, CID (i.e. cell phone number). The control server maintains a MANET node's neighboring CIDs table, a Power Consumption Table, PCT and Time Delay Table,TDT by the reports which are periodically sent by the MANET nodes. 4.2. MANET node configuration This section describes in details about the MANET node configuration and ad hoc network construction. 4.2.1. MANET node IP address configuration The MANET node IP address is configured by the control server. The control server has an IP address pool that can be dynamically allocated to the MANET node. The IP address used can be IPv4 or IPv6 address. The control server sends the IP address configuration information to the MANET node and the MANET node then uses this IP address to configure its MANET interface (802.11 wireless interface in this example). The IP address configuration policy can be configured by the mobile operator. Y.F Zhang, et al. Expires Feb. 5, 2009 [Page 6] Internet-Draft CCC for MANET July 2008 4.2.2. MANET node routing table construction When a MANET node wants to establish an ad hoc connection with another MANET node, it sends a request message to the control server. The control server then calculates a shortest path using Dijkstra algorithm [4] for that MANET node. In the routing table construction process, the QoS requirement is guaranteed according to the TDT. After forming the routing table, the control server sends it to the MANET nodes by the control network using GPRS link. Then the MANET node can use this IP address and routing table to communicate with its destination node in an ad hoc fashion. As demonstrated in figure 3, when node A wants to establish a connection with B, it sends a request to the control server. Before the connection is established, the control server calculates the shortest path by Dijkstra Algorithm, and allocates all the related node's IP address and routing table. In figure 3, node A and B are the session nodes, node 2 is the relay node, and node 3 and 5 are backup nodes in case of node 2 fails. They agree to participate the session. However, the shortest path does not include them. +------------------------------------------------+ | The shortest path | | +-----------+ +-----------+ | | |Node A |==============|Node 2 | | | +-----------+ +-----------+ | | | \ / || | | | \ / ||The | | | +--------------+ ||shortest | | | | Node 5 | ||path | | | +--------------+ || | | | || | | | || | | +-----------+ +-----------+ | | |Node 3 |--------------|Node B | | | +-----------+ +-----------+ | | | | | | | +------------------------------------------------+ Figure 3: Routing Management 4.3. Maintenance of the MANET In the case of MANET topology changing, the control server will find the PCT changes, so it applies Dijkstra algorithm again and forming a new routing table. This procedure may include new IP address configuration and old IP address withdrawal. If the control network cannot be used due Y.F Zhang, et al. Expires Feb. 5, 2009 [Page 7] Internet-Draft CCC for MANET July 2008 to poor signal power, the MANET node will use its default ad hoc routing protocol to construct a new routing table. And when the control network can be used, the MANET node then send the network changes to the control server, the control server then updates its PCT and TDT. 4.4. Demolition of the MANET When a MANET node wants to leave from a MANET, it sends a demolition request to the control server. The control serve then withdraws the IP address and updates its PCT and TDT. 4.5. Establishment of Multicast MANET The control server uses the topology information of the MANET to first calculate the shortest path using Dijkstra algorithm in each pair of MANET nodes and then calculate a minimum weight sub-graph[4]. 4.6. Session Control The control network can also interact with the application in session control. The details are illustrated in Section 5.4. 4.7. Control Sequences of the Formation of a Connection The following figure demonstrated the control sequence of the process of a connection establishment. +-------------------------------------------------------------------+ | | | +-------+ +-------+ +--------+ +------+ | | |Node A | |Node 1 | |Node B | |Server| | | +-------+ +-------+ +--------+ +------+ | | | | | | | | |------------|--------------|-----------|A want to connect | | | | | | | | | | | |Server calculate | | | | | |the shortest path | | | | | |and routing tables | | |<-----------|<-------------|<------------| | | | | | |Server allocate IP | | | | | |address and routing| | | | | |tables | | |<--------- |<----------- |<----------- |NodeA,NodeB,Node1 | | | | | |transfer data | | | | | | | +-------------------------------------------------------------------+ Figure 4: Control Sequence of Connection Establishment Y.F Zhang, et al. Expires Feb. 5, 2009 [Page 8] Internet-Draft CCC for MANET July 2008 5. Details of the Control Network 5.1. Client and Server There are two kinds of terminals, client and server in a control network. Client is installed on the cell phone while the server resides in the mobile operator's network. The clients and server communicate by the GPRS channel. Basically, Client sends the information of nodes up to the server and communicates with transport networks and the server calculates the routing table and send back Control Messages. 5.2. Structure of Control Message in Terminal and Relay Nodes 5.2.1. Structure of Control Message in Terminal Nodes The structure of control message includes header and body. The header is 4 bytes long and the body structure is decided by the header. The first Byte of the header is defined as the following: EstablishS 00000000 establish an ad hoc connection EstablishM 10000000 establish a network with multi-points Delete 11000000 delete the connection Refresh 11100000 request of renew the routing table Leave 11110000 request of leaving the network MyNeighbor 11111000 tell center the neighbouring points AckSNet 11111100 agree to join a ad hoc connection nAckSnet 11111110 disagree to join a ad hoc connection AckMNet 11111111 agree to join a multi-points connection nAckMNet 00000001 disagree to join a multi-points connection NetFlow 00000011 report the netflow of the point ParticipateNet 00000111 request of paricipation AllowIn 00001111 agree of the join of the CID nAllowIn 00011111 disagree of the join of the CID The second Byte is verification,which can be calculated by suming all bytes in the control message and using modular arithmetic with modulus 11111111.The third Byte is the length of the control message except the header. The fourth Byte is the CID. The body definition is as follows. EstablishS CID of the supposed opposite point EstablishM number of CID and the CIDs Y.F Zhang, et al. Expires Feb. 5, 2009 [Page 9] Internet-Draft CCC for MANET July 2008 Delete the ID supposed to be deleted Refresh null Leave null MyNeighbor number of CIDs and all the neighbouring CIDs AckSNet ID established nAckSNet ID established AckMNet ID established nAckMNet ID established NetFlow flow of the net(by k) ParticipateNetID established AllowIn ID established and CIDs permitted nAllowIn ID established and CIDs not permitted 5.2.2. Structure of Control Message in Relay Nodes The structure of control message in relay nodes is similar to that of terminal nodes. The header is defined as follows: AckEstablishS 00000000 agree to establish a ad hoc connection nAckEstablishS 10000000 fail to establish a connection AckEstablishM 11000000 agree to establish a multi-points connection nAckEstablishM 11100000 fail to establish a multi-points connection AckDelete 11110000 agree to delete the connection nAckDelete 11111000 fail to delete the connection DistributeRoute 11111100 give a routing table to the point AckLeave 11111110 allow the point to leave IsPartiSNet 11111111 ask the point if it likes to join the connection IsPartiMNet 00000001 ask the point if it likes to join the multi-points connection AckNetFlow 00000011 infos of flow AckMyNeighbor 00000111 neighbouring CIDs ToBeDeleted 00001111 the ID to be deleted AckParticipate 00011111 agree to join the network nAckParticiapte 00111111 disagree to join the network IsAllow 01111111 wether agree the CID's join The second Byte is verification,which can be calculated by suming all bytes in the control message and using modular arithmetic with modulus 11111111.The third Byte is the length of the control message except the header. The fourth Byte is the CID. Y.F Zhang, et al. Expires Feb. 5, 2009 [Page 10] Internet-Draft CCC for MANET July 2008 The body definition is as follows. st nd rd AckEstablishS ConnectionID in 1 byte, request/answer CID in 2 /3 byte st nd nAckEstablishS request/answer CID in 1 /2 byte st AckEstablishM ConnectionID in 1 byte, Participants CID in following byte NAckEstablishM Initiator's CID AckDelete ConnectionID nAckDelete ConnectionID DistributeRoute Routing Table Information AckLeave Leaving node CID st nd IsPartiSNet ConnectionID in 1 byte, request CID in 2 byte st IsPartiMNet ConnectionID in 1 byte, Participants CID in following byte AckNetFlow null AckMyNeighbor null ToBeDeleted ConnectionID to be deleted AckParticipate ConnectionID NAckParticipate ConnectionID st nd IsAllow ConnectionID in 1 byte, Joining node CID in 2 byte 5.3. Interface between Control Network & Transportation Network The senders receive the IP address of gateway from the control network, all the other messages received will be discarded except that from the right IP address. 5.4 Interface between Control network and APP The message that control network sends to the APP is defined as follows. AckEstablishS a connection's established nAckEstablishS a connection's not established AckEstablishM a connection's established nAckEstablishM a connection's not established AckDelete a connection's deleted nAckDelete a connection's not deleted AckLeave allow to leave IsPartiSNet ask whether to join IsPartiMNet ask whether to join ToBeDeleted the connection will be deleted IsAllow answer allow to join or not The message that the APP sends to the control network is defined as Y.F Zhang, et al. Expires Feb. 5, 2009 [Page 11] Internet-Draft CCC for MANET July 2008 follows. EstablishS establish a ad hoc connection EstablishM establish a multi-points connection Delete delete the connection Leave leave AckSNet acknoledge to join a connection nAckSNet disacknoledge to join a connection AckMNet acknoledge to join a multi-points connection nAckMNet disacknoledge to join a multi-points connection ParticipateNet participate a net of the ID AllowIn allow a CID to join nAllowIn not allow a CID to join 6. Security Considerations The security mechanism of Control Network depend on the security mechanism that provided by the mobile operator's network. The control server takes the responsibility to authenticate and authorize the MANET node. The inter MANET node's data transportation should be protected by shared key and the data should be encrypted. 7. IANA Considerations This document makes no requests to IANA. 8. Conclusions This document discusses a cellular base central control system that can be used for the mobile operator to control and mange a MANET network. 9. Acknowledgments The authors would like to thank the following individuals for their review, comments, and suggestions to improve the content of this document. Lin Zhang, Guijin Wang, Zhisheng Niu, Peng Kang, Wenxin Ning, Han Wang. Y.F Zhang, et al. Expires Feb. 5, 2009 [Page 12] Internet-Draft CCC for MANET July 2008 10. References 10.1. Normative References [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [2] http://ieee802.org/11/ 10.2. Informative References [3] Wang Jingwu,''Design and implementation Operational Wireless Ad hoc Control Server'', Tech. Report,Tsinghua University,May 2008. [4] Thomas H.Cormen et al,''Introduction to Algorithms'', Second Edition. MIT Press and McGraw-Hill, 2001. Section 24.3: Dijkstra's algorithm, pp.595- -601 Author's Addresses Yunfei Zhang China Mobile Communications Corporation Phone: +86 10 66006688 Email: zhangyunfei@chinamobile.com Intellectual Property Statement The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement Y.F Zhang, et al. Expires Feb. 5, 2009 [Page 13] Internet-Draft CCC for MANET July 2008 this standard. Please address the information to the IETF at ietf-ipr@ietf.org. Disclaimer of Validity This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Copyright Statement Copyright (C) The IETF Trust (2008). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. Y.F Zhang, et al. Expires Feb. 5, 2009 [Page 14]