Table of Contents
Overview of the Cisco 6260 Chassis
This chapter provides a general overview of the concepts used in the Cisco 6260 DSLAM (hereafter referred to as the Cisco 6260 or Cisco DSLAM chassis), and CDM software system. The Cisco 6260 provides end-to-end service by handling voice or data traffic, or both, between a subscriber home or office, a telephone central office (CO) facility, and various networks. CDM provides a means for you to manage the elements on the Cisco 6260 network.
This chapter includes the following sections:
The main components of a Cisco 6260 CDM system include a Cisco 6260 DSLAM with a network interface-2 (NI-2) card, a local SUN workstation (CDM server), CDM, and optional remote SUN workstations (CDM clients).
Figure 1-1 shows a typical deployment and interconnection example for the Cisco DSLAM, in which it is connected to a Cisco 6400 Universal Access Concentrator (UAC) system.
Figure 1-1: Cisco DSLAM Overview

Features of the main components of a Cisco 6260 CDM system include:
- The Cisco 6260 chassis houses an NI-2 card and a combination of Cisco 6260-supported line cards30 slots are dedicated for line cards and two slots for NI-2 system controller cards.
- The Cisco 6260 can be operated as a carrier class DSLAM with asymmetric digital subscriber line (ASDL) interfaces. The Cisco 6260 is intended for use in North American central office facilities.
- In addition to the line cards and the NI-2 card, the Cisco 6260 DSLAM accommodates a system I/O card that is installed on the backplane of the chassis. The I/O card provides DS3 ports for OC-3 and DS3 NI-2 configurations. The I/O card also provides a utility connector that supports remote alarm indications and network timing connections.
- The SUN workstations house the Cisco Element Management Framework (Cisco EMF) and CDM element manager software.
- If your network contains multiple SUN workstations, you must dedicate one workstation as the server, and all additional workstations as clients. Use the server as the repository and distributor of database information, and the clients to request information. The client workstations allow multiple users to monitor the managed network.
- Cisco EMF is the element management layer of the Cisco Service Management (CSM) system. It comprises the framework to support carrier-class element managers across Cisco service provider product lines.
- CDM is the management software application used to configure networks of Cisco IOS software-based DSLAMs, and manage the objects in the Cisco 6260 chassis.
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Note Cisco supplies only the Cisco 6260 chassis, Cisco 6260 supported cards, and the software applications. |
The Cisco 6260 with NI-2 operates as follows:
- Line cards send and receive subscriber line data (often Internet service) over existing copper telephone lines. The Cisco 6260 concentrates all traffic onto a single high-speed trunk for transport to the Internet or the corporate intranet.
- ADSL customer premises equipment (CPE) devices, which are connected to PCs or routers at a subscriber site, modulate data so that data on wire telephone lines is received by a Cisco 6260 at the telephone service provided CO facility.
The Cisco 6260 provides the following features:
- Has a 30-slot quad-port architecture that supports the DMT ADSL technology.
- Accommodates DS3 (digital signal 3) and OC-3 (optical carrier-3) single-mode and multimode NI-2 cards.
- Supports ANSI T1.413 Issue 2 discrete multitone (DMT-2) modems.
- Accommodates up to 120 ADSL subscriber lines.
- Is SNMP-manageable through Cisco IOS software.
- Has a nonblocking ATM switching architecture.
- Is a carrier-class multiplexer that functions in an installed configuration with or without plain old telephone service (POTS).
- Has installed configurations that handle
- Voice and digital data trafficUses ADSL technology to support up to 120 subscribers connected either directly or through a POTS splitter chassis. Filters separate voice and data signals when subscribers are connected to the Cisco 6260 through a POTS splitter chassis. Cables connected to the POTS splitter route ADSL digital data signals to line cards in the Cisco 6260 and voice signals to the CO facility switching network.
- Digital data onlyUses ADSL technology to support up to 120 subscribers connected to a Cisco 6260 directly from the CO facility main distribution frame (MDF).
- Can subtend multiple Cisco 6260 DSL access concentrators in a single network connection that is configured with
- DS3 NI-2 cards
- OC-3 single-mode or multimode NI-2 cards
You can link up to 13 Cisco 6260 chassis so that they can be served by a single network trunk port. This is called subtending. Subtending is economical because it reduces the number of ports that are needed in the aggregator or backhaul network to which the Cisco 6260s are connected.
Subtending is accomplished through the use of WAN interfaces (on the NI card). In a subtending arrangement, each chassis is connected by a WAN interface to the chassis above it in the subtending hierarchy, or, if the chassis is at the top of the hierarchy, to the network trunk. Each chassis is connected by one or more WAN interfaces to those below it in the hierarchy.
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Note Subtending refers to the host Cisco 6260 (called the host) and subtended refers to downstream Cisco 6260 DSLAM (called the child) in a subtended network. In a subtended network, you can have a maximum of 13 Cisco 6260 chassis1 subtending chassis and 12 subtended chassis. |
Three subtending configurations are possible:
See "Guidelines for Configuring a Subtending System" section for specific information regarding subtending the 6260 chassis. Refer to the Cisco 6260 Hardware Installation and Troubleshooting Guide for detailed information about subtending.
The Cisco 6260 chassis contains 32 card slots. Slots 10 and 11 are reserved for NI-2 cards. You can insert any other Cisco supported line cards in slots 1 to 9 and 12 to 32.
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Note To comply with NEBS requirements, blank faceplates should be installed in all empty card slots. |
An NI-2 card performs central processor, host, and system controller functions. The NI-2 card runs and is controlled by Cisco IOS software. The NI-2 card is available in several hardware configurations:
Network interfaces for DS3 type NI-2 cards are on the system I/O card. In the case of the OC-3 type, the NI-2 card faceplate provides the required network optical interfaces. The NI-2 card performs the following tasks:
- Contains the ATM switch fabric
- Provides the network WAN trunk interface (either DS3 or OC-3)
- Provides subtending interfaces to subtended Cisco 6260s with NI-2
- Controls timing and redundancy
- Provides CO facility alarm relay contact interfaces and an alarm cut-off switch
- Provides operating status visual and audible indications
- Performs subtending and other control functions
The DS3 type NI-2 card operates in conjunction with network interfaces supplied by BNC connectors on the system I/O card. A system I/O card supports the following tasks:
- Provides transmit and receive BNC coaxial cable network connections when you subtend Cisco 6260s that contain DS3 type NI-2 cards
- Provides wire-wrap pins for dedicated CO facility operating alarms
- Supports the aggregation of up to 12 additional subtended Cisco 6260s with NI-2, configured for DS3 operation, in a tree topology or in a daisy chain
The OC-3 type single-mode and multimode NI-2 cards operate in conjunction with network interfaces supplied by optical interface connectors on the OC-3 type NI-2 card faceplate. OC-3 type NI-2 card faceplates have two optical connector pairs that perform the following tasks:
- The top optical connector pair receives OC-3 ATM network transmit and receive trunk optical cables or OC-3 transmit and receive optical cables from the NI-2 card of a subtending Cisco 6260.
- The bottom optical connector pair accommodates receive and transmit optical cables from the NI-2 card of a subtended Cisco 6260 with NI-2 configured for operation in an OC-3 network.
The single-mode and multimode OC-3 type NI-2 cards support the aggregation of up to 12 additional subtended OC-3 type Cisco 6260s with NI-2 in a daisy chain configuration.
System I/O cards are also required on the OC-3 type Cisco 6260s to provide wire-wrap pins for dedicated CO facility OC-3 type NI-2 card operating alarms.
The Cisco 6260 system input/output (I/O) card performs the following tasks:
- Interfaces with a DS3 network trunk or provides a DS3 network trunk to subtended DS3-configured Cisco 6260s with NI-2.
- Permits up to 12 DS3-configured Cisco 6260s to be subtended.
- Provides relays and contact wire-wrap pins for dedicated CO alarms operated by Cisco IOS software.
- Provides the building-integrated timing source (BITS) clock.
The ATUC-1-4DMT card (hereafter referred to as 4DMT) is a discrete multitone (DMT) modulation high-density line card. The 4DMT card contains four modems: two on the card motherboard and two on an attached daughterboard.
The 4DMT line card supports
- ADSL communications with and without POTS in Direct Connect applications only
- Simultaneous 8032 Mbps downstream and 864 Mbps upstream data rates at each of its four modem ports
The 4DMT line card is compatible with an NI-2 card running Cisco IOS software in Cisco 6260 with NI-2. The NI-2 card is an advanced controller that operates the 4DMT card in the enhanced data serial bus (DSB) mode. The 4DMT card supports full ADSL rates on all four modems.
Ports are the means by which traffic is routed across the network, and services are connected within a system. In other words, traffic enters and exits the Cisco 6260 through ports.
The ports in the Cisco 6260 are defined by a port address. A port address is a logical identifier that is assigned to each network interface and line card. The system controller assigns port addresses when a card is entered into the system database.







Posted: Thu Aug 31 10:57:20 PDT 2000
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