针对集中式基于网际互连协议的语音传输(Voice over Internet Protocol,VoIP)语音通信交换系统(Voice Communication Switching System,VCCS)的互操作性需求,提出一种基于VoIP技术的中继通信解决方案。在集中式VoIP通信架构的基础上构...针对集中式基于网际互连协议的语音传输(Voice over Internet Protocol,VoIP)语音通信交换系统(Voice Communication Switching System,VCCS)的互操作性需求,提出一种基于VoIP技术的中继通信解决方案。在集中式VoIP通信架构的基础上构建中继通信模型,结合局向管理、冠号管理、路由管理以及会议管理等模块的协同运行给出VoIP中继通信的业务处理流程,并详细阐述中继会议的核心模块。最后,通过两种异型语音通信交换系统的中继通信对比测试,验证了文章提出的VoIP中继通信方法的可靠性和互操作性。展开更多
A novel framework for remote service discovery and access of IP cameras with Network address Translation (NAT) traversal is presented in this paper. The proposed protocol, termed STDP (Service Trader Discovery Protoco...A novel framework for remote service discovery and access of IP cameras with Network address Translation (NAT) traversal is presented in this paper. The proposed protocol, termed STDP (Service Trader Discovery Protocol), is a hybrid combination of Zeroconf and SIP (Session Initial Protocol). The Zeroconf is adopted for the discovery and/or publication of local services;whereas, the SIP is used for the delivery of local services to the remote nodes. In addition, both the SIP-ALG (Application Layer Gateway) and UPnP (Universal Plug and Play)-IGD (Internet Gateway Device) protocols are used for NAT traversal. The proposed framework is well-suited for high mobility applications where the fast deployment and low administration efforts of IP cameras are desired.展开更多
Two common kinds of security mechanisms used in session initial protocol (S1P) are analyzed. An improved HTTP digest authentication scheme is put forward based on the existing SIP authentication theories. This mecha...Two common kinds of security mechanisms used in session initial protocol (S1P) are analyzed. An improved HTTP digest authentication scheme is put forward based on the existing SIP authentication theories. This mechanism is combined with the merits of the HTTP digest authentication and the public key encryption, so the communicating parties complete two-way authentication and public key exchange in pre-calling, and the session key can be randomly generated in post-calling. The mixture of security encryption mechanism with public key encryption and symmetric-key encryption algorithm can ensure the security for network communication data. The emulation of the scheme is verified, and the security analysis is conducted in the end. The researches show that the simulations efficiency of this method is about 78% of HTTP's, and it can prevent four kinds of attacks including impersonating a server, offline password guessing attacks, relay-attack, and session monitoring.展开更多
随着会话初始化协议(Session Initial Protocol,SIP)的发展和推广,一些专有网络也部署了基于SIP协议的网络通信服务器和话音终端,但这些基于SIP协议的话音终端不能与专网中基于异步传输模式(Asynchronous Transfer Mode,ATM)交换体制的...随着会话初始化协议(Session Initial Protocol,SIP)的发展和推广,一些专有网络也部署了基于SIP协议的网络通信服务器和话音终端,但这些基于SIP协议的话音终端不能与专网中基于异步传输模式(Asynchronous Transfer Mode,ATM)交换体制的话音设备建立话音专线。为满足这种使用需求,针对专网中现有的网络通信服务器进行分析研究后对设备功能做了改进。改进后使用各类SIP话音终端与专网中基于ATM的话音终端进行专线测试,功能良好,完全满足用户的使用需求。展开更多
基于会话初始化协议(SIP)的VoIP系统在Internet上已经取得了广泛应用,但在目前的实际网络环境中,由于大量NAT设备的存在,使对等网络(P2P,Peer to Peer)之间的呼叫和数据通信难以实现。分析了四种NAT的类型特点,介绍了现有的NAT穿越方法...基于会话初始化协议(SIP)的VoIP系统在Internet上已经取得了广泛应用,但在目前的实际网络环境中,由于大量NAT设备的存在,使对等网络(P2P,Peer to Peer)之间的呼叫和数据通信难以实现。分析了四种NAT的类型特点,介绍了现有的NAT穿越方法,提出了一种基于STUN与TURN方式相结合的实现各种NAT穿越的VoIP系统设计方案。该方案对SIP信令采用可靠的TCP传输方式,对流媒体数据采取最大交付的UDP传输方式。经过校园网内部之间的网络环境测试,该方案达到了很好的接通率。展开更多
文摘针对集中式基于网际互连协议的语音传输(Voice over Internet Protocol,VoIP)语音通信交换系统(Voice Communication Switching System,VCCS)的互操作性需求,提出一种基于VoIP技术的中继通信解决方案。在集中式VoIP通信架构的基础上构建中继通信模型,结合局向管理、冠号管理、路由管理以及会议管理等模块的协同运行给出VoIP中继通信的业务处理流程,并详细阐述中继会议的核心模块。最后,通过两种异型语音通信交换系统的中继通信对比测试,验证了文章提出的VoIP中继通信方法的可靠性和互操作性。
文摘A novel framework for remote service discovery and access of IP cameras with Network address Translation (NAT) traversal is presented in this paper. The proposed protocol, termed STDP (Service Trader Discovery Protocol), is a hybrid combination of Zeroconf and SIP (Session Initial Protocol). The Zeroconf is adopted for the discovery and/or publication of local services;whereas, the SIP is used for the delivery of local services to the remote nodes. In addition, both the SIP-ALG (Application Layer Gateway) and UPnP (Universal Plug and Play)-IGD (Internet Gateway Device) protocols are used for NAT traversal. The proposed framework is well-suited for high mobility applications where the fast deployment and low administration efforts of IP cameras are desired.
基金Supported by the Central University Basic Research Special Fund Operating Expenses(2011ZM0033)
文摘Two common kinds of security mechanisms used in session initial protocol (S1P) are analyzed. An improved HTTP digest authentication scheme is put forward based on the existing SIP authentication theories. This mechanism is combined with the merits of the HTTP digest authentication and the public key encryption, so the communicating parties complete two-way authentication and public key exchange in pre-calling, and the session key can be randomly generated in post-calling. The mixture of security encryption mechanism with public key encryption and symmetric-key encryption algorithm can ensure the security for network communication data. The emulation of the scheme is verified, and the security analysis is conducted in the end. The researches show that the simulations efficiency of this method is about 78% of HTTP's, and it can prevent four kinds of attacks including impersonating a server, offline password guessing attacks, relay-attack, and session monitoring.
文摘随着会话初始化协议(Session Initial Protocol,SIP)的发展和推广,一些专有网络也部署了基于SIP协议的网络通信服务器和话音终端,但这些基于SIP协议的话音终端不能与专网中基于异步传输模式(Asynchronous Transfer Mode,ATM)交换体制的话音设备建立话音专线。为满足这种使用需求,针对专网中现有的网络通信服务器进行分析研究后对设备功能做了改进。改进后使用各类SIP话音终端与专网中基于ATM的话音终端进行专线测试,功能良好,完全满足用户的使用需求。
文摘基于会话初始化协议(SIP)的VoIP系统在Internet上已经取得了广泛应用,但在目前的实际网络环境中,由于大量NAT设备的存在,使对等网络(P2P,Peer to Peer)之间的呼叫和数据通信难以实现。分析了四种NAT的类型特点,介绍了现有的NAT穿越方法,提出了一种基于STUN与TURN方式相结合的实现各种NAT穿越的VoIP系统设计方案。该方案对SIP信令采用可靠的TCP传输方式,对流媒体数据采取最大交付的UDP传输方式。经过校园网内部之间的网络环境测试,该方案达到了很好的接通率。