China Netcom Group Labs Beijing 100032
Abstract By analyzing current development conditions of mainstream Instant Message technologies and services, some detailed discussion about technical solution and formal operation deployment strategies of P2P Instant
Message Services based on Internet is made. Several crucial problems of P2P Instant Message System about services management, interconnection with other instant message, security and profi t-making mode are analyzed, , and how to develop P2P IM Services is proposed.
Keywords P2P; Instant Message; Session Initiation Protocol; Profi t-making Mode
At present, the application of IM (Instant Message) is used very widely, it is able to realize the integrated services based on Internet such as IP voice, data, and images. At the same time, the fee with PC voice one another is almost free,in virtue of the realizing of voice PC to phone must through fi xed-line operator’s interconnection, the fee is cheaper though not free. The very-low-fee or even cost-free IM software heavily shunt the traditional voice services of the operators.
So need analyzing and research the IM, utilizing the technologies advantage of P2P IM to optimize operators own network and services, and bring forward the suited P2P IM scheme for operators faction. For the operators, the use of IM technologies based on P2P architecture would reduce communication equipment investment greatly, improve the network utilization rate and reduce the service development cost. And the operators could exploit many new value-added services based on P2P IM and make it become a new profi t increment point. This paper proposes a solution of the IM based on P2P from the aspects of technical realization and service deployment by analyzing current mainstream IM technologies.
Resently, with the rapid incensement of the number of the Internet users, the users of the IM also increase.
Based on the I-Research market expection, the IM users all over the world would increase from 490 million in 2007 to 650 million in 2010, and the scale of
IM market would increase from 150 million dollars to
280 hundred million dollars in 2010. The operators at home and abroad continuously propose new services.
England Telecom had put forward a new Internet service that from Yahoo IM product to a phone in
March 2004.China Telecom proposed Internet ‘CALL
ME’ IM system that provide the text message services among PC, PHS and mobile phone and the PC to
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phone voice service in November 2004, and the ‘CALL
ME’ update edition is tested in Guangdong province at present. China Mobile developed the IM Fetion based on Mobile Network that offering the text messages and voice services between a PC and a mobile phone in November 2006.China Union proposed the Mobile
Network IM UMS that offering the text messages and voice services between a PC and a mobile phone in
August 2007.China Netcom also provided CNCIM based on PHS in April 2007, and would propose CA based on Soft Switch. The development procedure of china IM is shown in fi gure 1.Figure 1(a) focuses on the time and fi gure 1(b) focuses on the function [1].
between different IM systems has become a serious problem[2,3].
Table.1 Contrast analyze of mainstream IM
(a)
For the profit-making mode, most IM platforms still use advertisement as their main way. This advertisement mode includes traditional, initiative and personal way. At the same time, it includes
Internet, wireless and fixed-line Increment Services.
The corporation mode makes profi t by providing IM services for enterprises. The virtual telecommunication operators collect fees form the users to a dial fixed or mobile phone by using the IM software, and make profi t with the IM brand patents.
(b)
Figure1 The development of IM in China
（(a)about time，(b）about function）
The contrastive analyis of current mainstream IM software such as QQ, MSN, TOM-Skype and Fetion according to the aspects of support network, work mode and protocol etc. is shown in table 1. It could be seen from table 1 that all of the IM platforms based on conventional C/S structure have their own private protocols except TOM-Skype, which is based on P2P mode and has standard protocol. So the IM system would have a bottleneck if the number of the users increases to a certain degree. At the same time, for the protocols not being opened, the interconnection
After analyzing the contrast of the mainstream IM architecture with P2P technical features, a technical solution of the P2P IM providing a online real-time communication service across Internet, fixed and mobile networks that realized anywhere real-time communication to the users within fixed-telephone,
PHS, PC, GSM mobile phone, CDMA mobile phone, GPRS mobile phone, 3G mobile phone and wifi/wimax mobile phone is proposed. The Internet communication services include the PC to PC text messages, presence of PC to PC, PC to PC voice, PC to PC video and PC to PC file transfer; the acrossnetwork data communication services consist of PC
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to PC text messages, presence of PC to PC and PC to
PC file transfer; and the across-network multimedia communication services are the PC to PC voices and
PC to PC videos. At the same time, the system also supply the increment services based on content with a series of IM applications and the interface with the other services platform or content providers, for example, many people online games and personal spaces etc.
management of users, platforms, contents and charges etc. In addition, the operation management level also provides the third-party interfaces. The physics topology of system is shown in fi gure 3.
The established super node consists of chord ring and common users node connected with its adjacent super node that composed of partially decentralized structure topology. At the beginning, a node is a common node, and after it has run for certain time,
Figure 2 Logical Architecture of P2P IM
The solution adopts the partially decentralized structure topology and SIP/SIMPLE protocol as its calling signal, and the logical architecture is shown in fi gure 2.
The access level is a terminal type of support services that including PC, wifi/wimax phone, fixed phone, PHS, GSM/GPRS/WAP mobile phone, CDMA mobile phone and 3G mobile phone etc. The network level is the uniform P2P overlay network above the access level, this level uses partially decentralized structure topology and is responsible for joining a peer and leaving a peer, choosing the calling route, maintaining the network stability with the chord algorithm and DHT algorithm. The service level is the system that could support services including
Internet communication, the across-network data communication, the across-network multimedia communication and the increment services. The o p e r a t i o n m a n a g e m e n t l e v e l i m p l e m e n t s t h e the node could be converted to a super node when the node itself inspect own have enough performance and accessibility (for example, have an IP address and be able to run stably for a long time). The platform management server and content management server mostly manage every super node. The correlate information of users is stored through a database server. The message cache server stores the off-line text messages etc of the users. This system could interconnect with the operators’ own operation support system and the operators’own increment services platform, SP/CP increment services platform and other IM systems through all kinds of interconnection gateway. All the IM services in this paper could be shown by WAP and WEB server.
Considering the network of the operator, it is suggested that try to implement this system in one province or in one district in a practical deployment at the beginning. The system of P2P IM deployed in
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a province or a district metropolitan-area networks
(MAN), at the same time, validating usability the mechanism of P2P and the users experience effect by trial the each service function of P2P IM. As the
P2P architecture continuously mature, the mechanism of control and management improved, the market needs farther expand, the accumulate rich operation experience step by step, the internet bandwidth farther increased and mobile terminal equipment its performance better etc, we could deploy the system of P2P IM in core network. In this time, the system deployment would be very flexibility that adjust the dispose of super node which could deployed in core network, a province of backbone network or MAN, and super node’s join, leave, failure all couldn’t affect the system stability.
The solution of this paper proposed is a P2P IM system which could management, controlled and in the registration stage should be checked. Between the validate communication the users could negotiate a shared key which used for data transmission or communication stage. The system also provides the functions of platform management and maintenance, content release and management, system configure and management, long-distance monitoring and faults diagnose etc.
A t p r e s e n t , m u c h I M s o f t w a r e h a v e m a n y differences in the service function interface, and the description of data format that caused the interconnection of different IM applications has became a serious problem. Now there are two solutions, one is based on gateway, and the other is based on multi-protocol client. In this paper, a gateway is adopted to realize the interconnection between one
IM and another.
O n a c c o u n t o f t h e r e a l - t i m e c h a r a c t e r o f
I M a p p l i c a t i o n t h a t c a u s e d t h e n e t w o r k attack spread more fast and the result also more seriously through IM. We should design a specific information security IM system structure for IM garbage messages. For the security of transmission channel, a very credible e n c r y p t e d c h a n n e l mechanism is needed but
Figure 3 Physics system topology of P2P IM there would not be a very high computing complexity. And for the enterprises, it is suggested to build their own EIM (Enterprise IM) server inside, run the specifi c IM services, inspect and note the fl ow of IM and the operation of IM users to ensure the security of IM services [4].
operated. Before user login the system, user should send certificate request to authenticate server and through negotiation way to authenticate. The users could login the system only using the authentication.
After the user logins the system successfully, the user need to establish a communication or exchange data with the equity peer. Only after the successfully login the system, the users can search their equity peer information. Before the users exchange data, the certificate which awarded by authenticate server
When the operators develop the P2P IM services could earn function fee by providing the IM transmission function. The mobile IM could adopt short message and IM client mode, the short message charge basically by month and the client mode by fl ow. At the same time, entirely deploying Increment
Services about Internet, wireless, fixed-line etc to
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attain the aim that through IM drive the Increment
Services increased and through Increment Services attract the IM uses rise. The operators also may combine with the IM services CP/SP to cooperate and drive the whole IM industry chain harmonious developing.
Except the tradition advertisement mode, the operators could attempt new mode including initiative and personal etc. For enterprise customers, the operators can provide IM servers and IM terminals to supply the IM services. And the fee of the PC to phone voice is also collected by the gateway.
IM has become one of the important Internet applications after E-mail and web. The current IM architecture mostly bases on the C/S mode. The particular technical advantages of the IM system based on P2P architecture would be shown when the users and the services increase. This paper focuses on designing a logical and network architecture of
P2P IM, analyzing some crucial problems about the management, interconnection, security and profitmaking mode of the P2P IM systems, and giving some practical deployment suggestions for the systems of
P2P IM.
[1]
[2]
[3]
[4] iResearch market consultation. http:// www.iresearchgroup.com.cn, 2007
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Network: Architecture, Application and
Design. Beijing: Tsinghua Press,2007
YANG Tian-lu, LIU Yu-hong etc. The principle of P2P network technology and the examples of system development [M].
Beijing: Post&Telecom Press, 2007
ZHANG Wen-mao, ZHANG Miao etc.
Instant Messaging: the Present and the Future. Mini-Micro Systems of
Computers, 2007, vol.28, no.7, pp.1162-
1168.
作者简历
China Netcom Group Labs, Beijing, 100032, China
China Netcom Group Labs, Beijing, 100032, China
2008 06 17