Implementing Cisco Collaboration Core Technologies (CLCOR)

Cisco Expressway is designed to facilitate secure business-to-business communications and provides secure firewall traversal for remote devices. These functionalities enhance the collaboration architecture by enabling seamless and secure communication beyond the corporate network and ensuring that remote users can securely connect to the internal network.

To extend the corporate phone system to mobile users connecting through the internet with their own devices, Cisco Expressway-C and Expressway-E are the most suitable options. These elements are designed to simplify remote and mobile access by providing secure firewall traversal and signaling between the internal network and the mobile devices, ensuring seamless connectivity without complex configurations for end users.

To design a load-balancing solution using SRV records, two key factors must be considered: priority and weight. The priority value helps the client determine which host to contact first. In cases where multiple hosts share the same priority, the weight value is used to decide the proportion of traffic each host should handle. For cube1.abc.com to handle 60% of the calls, its SRV record should have a higher weight compared to cube2.abc.com, which will handle 40% of the calls. Both records should use the same priority to balance the load correctly. Therefore, the records should be: _sip._udp.abc.com 60 IN SRV 1 60 5060 cube1.abc.com and _sip._udp.abc.com 60 IN SRV 1 40 5060 cube2.abc.com.

The Cisco Expressway Series provides the functions of interworking of SIP and H.323 protocols, allowing different types of communication systems to interact seamlessly. Additionally, it supports endpoint registration, enabling endpoints to register with the Expressway for communication purposes. These capabilities are essential for ensuring smooth communication and interoperability within a network.