Cisco AS5800 Product Overview 1-7
Functional Overview
The Cisco AS5800 is a high-density, ISDN and modem W AN ag gregati on system that pro vides bot h
digital and analog call termination. It is intended to be used in service-provider dial
point-of-presence (POP) or centralized-enterprise dial environmen ts. The dial shelf cards and the
host router shelf communicate over a nonblocking interconnect th at supports 100- Mbps full-dupl e x
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 wh ile the system is powered on. Dial s helf
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 i s remo ve d, the interc onnect
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 Cisco5814 dial shelf and a Cisco7206 router shelf. If you are installing
multiple access serve rs, a system controller is available, which provi des a “single system” view of
multiple POPs.
The system controller for the access server includes the Cisco3640 router running CiscoIOS
software. The system controller can be installed at a rem o te facility so that you can ac cess 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 Telne t connection. The
system controller also provides performance monitoring and accountin g data collect ion 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 data base mana gemen t syste m, polli ng e ngin e,
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 appropria te telc o servic es. Digita l or ISDN ca lls
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 tra nsmits and re cei v es PCM- encode d anal og data
to and from the modem cards. Then the dial shelf and the rout er shelf e xchange fra med packet s 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 logi c and sy stem
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.