瘦客户机控制协议(SCCP)

瘦客户端控制协议(SCCP)是一种私有的线侧协议，最初由Selsius创建。1998年，思科以1.45亿美元的现金和股票收购了Selsius。新收购的Selsius Call Manager平台使用基于Intel的标准PC架构，所有与时分复用(TDM)资源的连接都使用PCI扩展卡完成。该平台有模拟卡(中继或站)和网关接口(T1或E1)，它们都使用一种称为瘦网关控制协议(SGCP)的协议。SCCP是使用TCP端口2000的线侧协议，负责呼叫管理器和IP电话(当时是12SP+和30VIP)之间的通信。在撰写本文时，呼叫管理器中的SCCP注册在思科IP电话MAC地址前面加上SEP (Selsius以太网电话)。所有Selsius PCI扩展卡都是EoS(销售结束)和EoL(生命结束)，但提到它们是为了了解网关中使用SCCP的历史，以及SGCP协议功能如何合并到SCCP中。瘦网关控制协议是用来在呼叫管理器和网关接口之间通信的协议，使用TCP端口2001用于T1和E1数字网关接口(SDA = Selsius数字接入)，TCP端口2002用于模拟网关接口(SAA = Selsius模拟接入)。TCP端口2001和2002仍然用于路由器和交换机生成的自动QoS策略，以确保所有语音信令协议在网络上获得带宽保证。目前，SGCP协议已不再使用，但SCCP是VG248网关平台支持的唯一协议。 The VG248 is a voice gateway with two female RJ-21 (amphenole) connectors. Each RJ-21 interface connects 24 FXS (Foreign Exchange Station) ports that connect analog devices with two-wire tip and ring connections. Punching down the RJ-21 connector cable to 110 blocks will surely test your patience. Fortunately, Cisco partners re-sell 110-blocks with RJ-21 connectors that match the pin out on the VG248. The VG224 is an EoS gateway platform that offers 24 FXS analog gateway interfaces. The VG224 supports the MGCP and H.323 protocols, but must use SCCP to support the entire supplementary service feature set. Supplementary services are voice feature such as: call hold, call park, conferencing, call transfer, etc. SCCP is very similar to MGCP in that there is minimal configuration that occurs on the Cisco IOS gateway platform. Most of the SCCP controlled gateway configuration is performed on the Call Manager platform. Cisco Unified Communications Manager (CUCM) version 4.2 and Cisco Unified Communications Manager Express (CUCME) version 3.2.2 introduced SCCP support of FXS gateway interfaces. Use the Cisco Feature Navigator available at www.cisco.com/go/fn to find the IOS version and feature set that supports SCCP Controlled Analog (FXS) Ports with Supplementary features in IOS Gateway for the IOS based gateway hardware in question. SCCP controlled FXS voice ports support many supplementary service features not supported by H.323, SIP, or MGCP gateway interfaces. A link to a detailed SCCP Controlled Analog (FXS) Ports with Supplementary features in IOS Gateway configuration has been provided for your reference. SCCP is also leveraged as the protocol in which CUCM communicates to DSP (digital signal processor) resources in gateways to provide hardware based conferencing and transcoding functionality. A link to an example of this configuration has been provided. The next blog post will examine the call survivability features of various gateway protocols. Feel free to post comments or ask questions about anything discussed in this blog. What gateway protocol do you use? Why did you select that gateway protocol and what advantage does it bring? Global Knowledge’s GWGK, CVOICE, CIPT, and IPTX classes offer more detailed information regarding gateway interfaces.www.globalknowledge.com/ciscoCisco Press Books CIPT1http://www.ciscopress.com/bookstore/product.asp?isbn=1587054833GWGKhttp://www.ciscopress.com/bookstore/product.asp?isbn=158705258XSCCP控制模拟(FXS)端口的补充功能，在Cisco IOS网关http://www.cisco.com/en/US/docs/ios/12_4t/12_4t2/ht1vg224.htmlVG248http://www.cisco.com/en/US/products/hw/gatecont/ps2250/products_data_sheet09186a008007c9bb.html使用DSP资源配置示例:CallMananger网络中IOS语音网关的增强转码和会议http://www.cisco.com/en/US/products/sw/voicesw/ps556/products_configuration_example09186a008084fe1f.shtml