摘要
彩铃作为2G时代最成功的增值业务之一,在3G网络中也迎来了自己的升级版IMS多媒体彩铃。IMS多媒体彩铃使用SIP协议做为呼叫控制协议并通过早媒体的方式为主叫播放彩铃铃音。本文在IMS多媒体彩铃业务网关模式呼叫流程的基础上,讨论了一次呼叫过程中触发两次或多次多媒体彩铃业务时的呼叫信令流程,指出了现有早期媒体类业务解决方案中存在的问题,提出了一种通过扩展"P-Early-Media"头域传递早媒体协商结果的方式,当触发多个早媒体业务时,避免业务间嵌套执行的机制。
Colorful Ring Back Tone（CRBT） Service is one of the most successful value-added services of 2G, has evolved to Multimedia Ring Back Tone（MRBT）.MRBT service is based on IMS （IP Multimedia Subsystem） core network, and using SIP （Session Initiation Protocol） to manage the call procedure. This paper discusses the scenarion and the siginal process when the MRBT service has been triggered more than once during a call using gateway mode. Then it analyses the existed problem duiring the early media negotiations and the results it may lead to.At last, this paper proposes a solution by extending the ＂P-Early-Media＂ header field to bring the early media negotiation results and the behavior of P-CSCF（Proxy Call Session Control Function） and other application servers.
出处
《软件》
2012年第11期50-53,共4页
Software
