Cisco Systems AS5800 manual Functional Overview

Functional Overview

Functional Overview

The Cisco AS5800 is a high-density, ISDN and modem WAN aggregation system that provides both digital and analog call termination. It is intended to be used in service-provider dial point-of-presence (POP) or centralized-enterprise dial environments. The dial shelf cards and the host router shelf communicate over a nonblocking interconnect that supports 100-Mbps full-duplex service.

The Cisco AS5800 supports high-density dial aggregation and integrates with Cisco AS5200 and AS5300 access servers for scaling your service provider network. The access server also supports high availability of service through online insertion and removal (OIR) capabilities and redundant power supplies that are hot swappable. All active components within the dial shelf chassis support OIR, which allows components to be removed or replaced while the system is powered on. Dial shelf cards can be busied-out through the software to avoid loss of calls.

Caution In order to maintain traffic flow in a single dial shelf controller (DSC) configuration, the DSC shouldn’t be removed while the system is operational. If the DSC is removed, the interconnect link between the DSC and router shelf will be lost and all other dial shelf cards will go down. The router console port will display the following message:

AUG 2 10:57:02.017 CST: %DSC_REDUNDANCY-3-BICLINK: Link to active DSC down

The access server includes a Cisco 5814 dial shelf and a Cisco 7206 router shelf. If you are installing multiple access servers, a system controller is available, which provides a “single system” view of multiple POPs.

The system controller for the access server includes the Cisco 3640 router running Cisco IOS software. The system controller can be installed at a remote facility so that you can access multiple systems through a console port or Web interface. You can download software configurations to any Cisco AS5800 using Simple Network Management Protocol (SNMP) or a Telnet connection. The system controller also provides performance monitoring and accounting data collection and logging.

In addition to the system controller, a network management system with a graphical user interface (GUI) runs on a UNIX SPARC station and includes a database management system, polling engine, trap management, and map integration.

The dial shelf contains ingress interfaces (CT3/CT1/CE1/PRI) that terminate ISDN and modem calls, and break out individual calls (DS0s) from the appropriate telco services. Digital or ISDN calls are terminated onboard the trunk card HDLC controllers, and analog calls are sent to modem resources on the modem cards. As a result, any DS0 can be mapped to any HDLC controller or modem module.You can install multiple ingress interface cards of like or different types, which enables you to configure your systems as fully operative, port redundant, or card redundant, depending on your needs.

Trunk cards and modem cards are tied together across a time division multiplexing (TDM) bus on the dial shelf backplane. The backplane TDM bus transmits and receives PCM-encoded analog data to and from the modem cards. Then the dial shelf and the router shelf exchange framed packets using a proprietary interconnect cable for further processing.

The dial shelf also contains a DSC card that provides clock and power control to the dial shelf cards. Each dial shelf controller card contains a block of logic referred to as the common logic and system clocks. This block generates the backplane Stratum-4 compliant 4-MHz and 8-KHz clocks used for interface timing and for the TDM bus data movement. The common logic can use a variety of sources to generate the system timing, including an E1 or T1 input signal from the BNC connector on the dial shelf controller card front panel. The clock source can also be telco office timing units (BITS clocking) extracted from the network ingress interfaces.

Cisco AS5800 Product Overview 1-7