可生存的远程站点电话第2部分

此博客将讨论在上次博客中启动的思科SRST对话。在思科IP手机寄存到Cisco SRST网关后，Cisco IP电话将继续向主Cisco Unified Communications Manager（CUCM）服务器保持保持活动。当主CUCM服务器可用时，连接监视器持续时间计时器必须在手机重新注册到主CUCM服务器之前到期。默认情况下，连接监视器持续时间默认为120秒，但可以在CUCM设备池配置中配置。Cisco IP电话在正常操作期间将主动TCP连接与其主和备份CUCM服务器都保持有源TCP连接。SRST技术假定思科IP电话具有有效的配置文件。手机的配置文件将发送到SRST路由器，允许路由器根据配置文件动态加载电机和ePhone-DN配置。SRST 7.1 supports the following number of phones and directory numbers per router platform: Router Phones Directory Numbers 1861 15 48 2801 25 256 2811 35 144 2821 50 192 2851 100 288 3825 350 960 3845 730 960 6500 CMM 480 960 Let’s look at an example of a branch office with 50 phones using a 2811 series router. Management would need to decide which 35 phones would be supported in SRST during a WAN outage. Device pool #1 would be provisioned with an SRST reference, while device pool #2 would be provisioned without an SRST reference. Fifteen of the phones would not be available during the outage. If the same example site had (2) 2811 routers, the site could accommodate 70 phones total. The default gateway of the site is probably a virtual IP address of HSRP and could not be used because the phones would all be steered to the active router. Two SRST references would need to be configured to load share the SRST references between the two SRST routers. In the next blog, we will take a look at an SRST configuration.