General Description. Overview. Introduction CHAPTER

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1 CHAPTER This chapter contains the following sections: Overview, page - Introduction, page - Configuration Data, page -3 Management, page -5 Maintenance, page -7 Physical Characteristics, page -8 Timing, page - Specifications, page -3 Overview This document describes the features and functionality of the Cisco 80 Broadband Termination Unit as well as providing a background to some of the more complex concepts introduced along with this new technology. Note The information in this Product Overview describes features already included within the product, as well as some features under development for later releases. This information is subject to change. Cisco is dedicated to the continuous improvement of this product, and new features or improvements may be available. Consult your Cisco representative for more information. This guide describes the features and operation of the Cisco 80 device and how it functions in the networking environment. Introduction As service providers continue to deploy ATM infrastructures within the carrier cloud, another requirement emerges at the edge of the public ATM network - a cost-effective way to achieve termination of ATM services, and connect private ATM networks to public ATM offerings. Cisco 80 units located at the edge of the carrier s ATM network can be used to effectively deliver an ATM source to multiple -

2 Introduction Chapter customers. Using information accumulated by the Cisco 80, the network operator can assess the QoS (Quality of Service) of each VC, control the network s availability and serviceability, provide essential tools for billing, and perform preventive maintenance. The Cisco 80 is an ATM network termination device designed for installation at the edge of the public ATM networks. It offers carriers and service providers powerful capabilities required for operating these networks - ensuring quality of communication services, monitoring network performance, measuring usage and managing network resources. Information accumulated in the Cisco 80 can be used by the network operator to access: the Quality of Service (QoS) for each individual Virtual Channel (VC), network availability and serviceability. These are necessary tools for billing and preventive maintenance. The unit includes three ATM interfaces, with a wide range of hot-swappable line interface modules (LIMs) for media and bit rate adaptation. A CSM module enables using the third port as a separate entity and not just as a backup and is used to provide circuit emulation services (CES). This is especially useful for transmission of voice or data from the private telephone exchange (PBX) via the CSM to the ATM network. The Cisco 80 is an optimal solution for network operators who wish to provide an ATM source to their customers. Using the Cisco 80, network operators can easily distinguish between faults originated in their networks, and faults originated in the user s network. System Features The following features are included in the Cisco 80: Quality of Service (QoS) supervision of up to 8 bi-directional Virtual Connection (VC) Performance monitoring Traffic management, including Policing, two-level traffic shaping Fault segregation Remote preventive maintenance Complete data collection in non-volatile memory Variety of hot-swappable interfaces for media and bit rate adaptation Ports for Facility Protection Switching Automatic Protection Switching Power Supply configurations (fixed and removable) Fully remote SNMP based management Three-port engine, where one port is connected to a customer network, a second port is connected to a network service provider, and a third port may be connected either as a backup for the network port or as a user port. Supports full range of VPI and VCI combinations Performance of the Usage Parameter Control function as defined in ITU-T I.37 Allows the Operator to select the policing action. Performance of Operation, Administration and Maintenance operations for the various levels of transmission as defined in ITU-T I.60. Accumulation of Performance Monitoring and Policing information in non-volatile memory at 5 minute intervals for 4 hours, to enable powerful fault analysis and preventive actions. -

3 0/00 Base-T Chapter Configuration Data The ports support various types of line interfaces for optical and electrical media, and for different line rates. Operator and User interfaces can be of any type. The Compact Subscriber Module/CES service on E/DS interfaces may be used in either of the user ports. Synchronization to any one of the received signals, or to an external timing signal (with Holdover option). Internal timing source Locally managed through an ASCII terminal, or using an in-band PVC based on SNMP protocol and with RFC 483 encapsulation. E/T Support Figure - shows a general view of the Cisco 80 System. Figure - Cisco 80 General View PWR PS PS SYS Reset LIM-E/T-SH INTERFACES 3 LIM-55MM-SH CSM 780 Tx CISCO Alarm Rx Active 4 Configuration Data Currently available LIMs OC-3c/STM-. Single Mode Fiber short haul - 55Mbps OC-3c/STM-. Single Mode Fiber long haul - 55Mbps OC-3c/STM-. Multi-Mode Fiber - 55Mbps STM-. Electrical G.703 STM-. Electrical UTP DS3-45 Mbps E3-34 Mbps DS/E Mbps / Mbps CES-DS/E / Mbps Note For LIMs of less than STM- rates in the Network direction, it is recommended that a Traffic Shaper be used -3

4 Configuration Data Chapter ATM Parameters Network Switching VPC, Shaping Performance Monitoring Continuity Check End Point VPI/VCI PCR, SCR, CDV, MBS Enable, Disable Enable, Disable End to end, Segment Ethernet 00-base-T IEEE 80.3 Rate 0 baset/ 00 base Tx Duplex Full / Half Auto negotiation Enable / Disable E3 Parameters Framing G.83, G.75 Mapping PLCP, G.804 DS3 Parameters Framing C-bit parity Mapping PLCP, G.804-4

5 Chapter Management E Parameters Framing G.704 DS Parameters Framing SF/ESF CSM Parameters Framing Same as E/DS framing Data Transfer Mode Structured (SDT)/Unstructured (UDT) Transmit Clock Recovery Same as T/E + adaptive SRTS (optional) Management The Cisco 80 is used either as a fully remote management unit which uses in-band SNMP management through VCs, or a local out-band-management unit using a serial port. The manager can control the Cisco 80, configure all the parameters, import usage parameters into billing application, read the status, performance and inventory information and perform preventive maintenance operations. Two software versions are stored, these versions can be remotely downloaded and selected. Several password-protected levels of access are provided. Monitoring The system accumulates PM parameters at all transmission levels for each port and at the VP or VC level for up to 8 bi-directional connections. 96 reports of 5 minute intervals are stored in the non-volatile memory. Dependability parameters such as cell loss ratio and cell misinserted ratio are also computed. Performance monitoring data can be used by the operator for different actions such as deciding on preventive action before a hard failure occurs. This ensures discovery of network weak spots. Policing The Cisco 80 monitors ATM traffic parameters to verify compliance of the cell stream to the traffic contract set at the connection provisioning. In the case of contract violation the operator can decide to drop violating cells, tag violation cells or count only. The operator can set the Cisco 80 attributes in -5

6 Management Chapter Policing Strategy each direction of the connection. For example, the operator may choose to drop violating cells incoming from the user to protect the network resources, and to count violating cells incoming from the network to assess the network performance. Low priority cells, high priority cells, and non-conforming cells are accumulated for each side of each connection in the same way as the performance monitoring parameters. At the ATM layer several types of service categories are provided. These categories relate traffic characteristics and QoS requirements to network behavior. Service categories are distinguished as being either real-time or non-real-time. For real-time traffic there are two categories, CBR and VBR-, distinguished by whether the traffic descriptor contains only the Peak Cell Rate (PCR) or both PCR and the Sustainable Cell Rate (SCR) parameters. The non real-time categories are VBR, VBR3 and UBR. Constant Bit Rate (CBR) Service Category The Constant Bit Rate (CBR) Service Category is used by connections that request a static amount of bandwidth that is continuously available during the connection lifetime. This amount of bandwidth is characterized by a Peak Cell Rate (PCR) and the Cell Delay Variation (CDV) value. The basic commitment made by the network to a user who reserves resources via the CBR capability is that once the connection is established, the negotiated ATM layer QoS is assured to all cells when all cells are conforming to the relevant conformance tests. In the CBR capability, the source can emit cells at the Peak Cell Rate at any time and for any duration and the QoS commitments remain valid. (See Table -). The amount of cells transmitted at the link rate is limited by the CDV. Real-Time Variable Bit Rate (VBR) Service Category The real-time VBR category is intended for real-time applications, i.e. those requiring tightly constrained delay and delay variation, as would be appropriate for voice and video applications. VBR connections are characterized in terms of a Peak Cell Rate (PCR), Cell Delay Variation (CDV), Sustainable Cell Rate (SCR) and Maximum Burst Size (MBS). Sources are expected to transmit at a rate which varies with time.(see Table -). Non Real-Time Bit Rate (VBR, VBR3) Service Category The non real-time VBR category is intended for non real-time applications which have bursty traffic characteristics and which are characterized in terms of PCR, CDV, SCR and MBS. For those cells which are transferred within the traffic contract, the application expects a low cell loss ratio. Non real-time VBR service may support statistical multiplexing of connections. No delay bounds are associated with this service category.(see Table -). Unspecified Bit Rate (UBR) Service Category The Unspecified Bit Rate service is intended for non real-time applications i.e. those not requiring tightly constrained delay and delay variation. Examples of such applications are traditional computer communications applications, such as file transfer and . UBR service does not specify traffic related service guarantees. No numerical commitments are made with connection. (See Table -). -6

7 Chapter Maintenance Table - Table of Traffic Parameter Attributes Attributes Traffic Parameters ATM Layer Service Catagory CBR VBR- VBR-, 3 UBR PCR and CDV specified specified SCR, MBS, CD N/A specified N/A. Represents the maximum rate at which the ABR source may ever send. The actual rate is subject to the control information. These parameters are either explicitly or implicitly specified for PVCs or SVCs. Line Interface Modules (LIMs) A large variety of hot-swappable LIMs are supported, featuring media and bit rate adaptation. The LIMs supported are optical long and short range OC-3c/STM-, electrical STM-, E3/T3, E/T and CSM. The Cisco 80 features 3 ATM ports. The second network interface can be used to provide facility protection switch function or to subscribe multiple users to the public ATM service provider. An External timing signal can be connected and an external timing signal output is provided by the Cisco 80. An internal timing source with hold-over support is also provided. Maintenance The Cisco 80 processes alarms at the transmission levels and the F4 and F5 ATM connection levels as defined in the relevant ITU standards. The Alarms Indication Signal (AIS) and Remote Defects Indication (RDI) alarms at the VP and VC levels are handled in accordance with the ITU-T I.60 standard. The Cisco 80 can be defined as the connection end point, or as a segment end point, allowing the network operator to segregate alarms originated within its network from alarms generated in the user s network. Continuity Check cells provide the ability to alert the network manager in case of Loss of Connection in any of the provisioned VC s. To help in fault localization, loopback can be activated at Line Interface layer and ATM layer. Loopback cells are fully supported at the VC and VP levels. Fault analysis is further supported with an event log file that records the last 000 events which are stored in the non-volatile memory. Traps can be sent to the network manager in case of alarms, excessive policing, performance monitoring (PM) threshold crossing and deviations from QoS agreements. The connections can be set as segment end points to terminate the network operator s segment. In this case, end-to-end alarms are monitored and reported. Loops can be performed at each port. The signal can be looped towards the network or towards the equipment. Loopback cells can be generated for each connection, and received loopback cells are looped back at the termination points. External alarms can be connected to the Cisco 80. Any change in the alarm status is reported to the manager. The Cisco 80 provides an external alarm dry contact indication. The Cisco 80 handles the alarms at the Regenerator, Multiplexer, and Transmission Path levels for the transmission signal, and the F4 and F5 levels for the ATM connections as defined in ITU-T I

8 Physical Characteristics Chapter Performance Monitoring (PM) PM data provides a powerful tool for troubleshooting and for network performance assessment. After analyzing the PM, preventive actions can be taken before a hard failure occurs. The Cisco 80 accumulates PM data for the transmission signal, and for each ATM connection. PM data includes various raw parameters such as: Code Violations, Lost Cells, etc.; along with variables computed on the basis of these parameters such as: Errored Seconds, Severely Errored Seconds, etc. Parameters and variables are accumulated in 5-minute increments. Data accumulation The last 96, 5 minute interval, PM and UPC statistics are stored in non-volatile memory. A 000 entries log file is also stored in non-volatile memory. Full Manageability The Cisco 80 contains an SNMP agent, making it fully manageable using either the Cisco 80 console management application, or MIB browsing facilities through the in-band control PVC. The Cisco 80 parameters can be set, the performance can be monitored and faults, and maintenance operations can be performed. Upgrades to the Cisco 80 can be downloaded through the in-band PVC. Physical Characteristics This section provides information on the physical construction and the configuration options available for the Cisco 80. The Cisco 80 standalone unit can be desk-mounted. Several Cisco 80 units, however, can be installed in a standard 9 rack (as shown in Figure -). Each Cisco 80 unit has a total capacity of 3 LIM modules. -8

9 0/00 Base-T Chapter Physical Characteristics Figure - Rack Installation PWR PS PS SYS Reset LIM-E/T-SH INTERFACES 3 CISCO 80 PWR PS PS SYS Reset 0/00 Base-T LIM-E/T-SH LIM-55MM-SH Tx CSM 780 Alarm INTERFACES 3 LIM-55MM-SH Tx CISCO 80 PWR PS PS SYS Reset 0/00 Base-T LIM-E/T-SH INTERFACES 3 CSM 780 Rx Active 4 Alarm LIM-55MM-SH CSM 780 Tx Rx Active 4 CISCO Alarm Rx Active 4 Modules A large variety of hot-swappable modules are supported, featuring media and baud rate adaptation. A listing of the module versions can be seen in the Configuration Data section in this chapter. Figure -3 illustrates a typical LIM unit. Several LIM modules attached to the Cisco 80 unit can be seen in Figure -4. Figure -3 Typical LIM Unit LIM-E/T-SH Figure -4 Single Cisco 80 Unit with LIM Modules -9

10 0/00 Base-T Physical Characteristics Chapter PWR PS PS SYS Reset LIM-E/T-SH INTERFACES 3 LIM-55MM-SH CSM 780 Tx CISCO Alarm Rx Active 4 The CSM (Compact Subscriber Module) optionally replaces a user LIM. Figure -5 shows the CSM 780 front panel with its four output connectors and alarm status LEDs. Figure -5 Front Panel of CSM-CES LIM CSM-4ET Tx Rx Alarm Active Site Planning Requirements Grounding Clearance The Cisco 80 is powered immediately on connection to the power source. The input voltage may vary from 00 to 40VAC and the maximum input power is 60 Watts per unit. A slow blow fuse is used to protect the input power line. The Cisco 80 unit must be properly grounded at all times in order to protect the user and the equipment from damage due to a lightning strike or contact with high voltage lines. The DC power cable must also include a third conductor or a braided wire shield for ground connection. Where applicable the casing must also be separately grounded in accordance with local regulations. The individual modules are grounded through their connection to the backplane. The Cisco 80 must be kept at least 30 mm from any other Cisco 80. This is the distance measured from the left, right or back. The units may be stacked one on top of the other. -0

11 Chapter Timing External Connections The Cisco 80 interfaces and the required connections comprise the following characteristics: Fiber-Optic Interfaces: long and short ranges E and T Interface Connections CSM Interface Connections STM- Electrical Interface Connections E3 and T3 Interface Connections External Clock Connection External Alarm Connection Ethernet Interface (optional) RS-3 Interface Electromagnetic Compatibility Requirements The Cisco 80 has been designed to comply with the various electromagnetic compatibility (EMC) standards (EMI/RFI) applicable to data transmission equipment. Timing The Cisco 80 will automatically switch between clock sources when a loss is detected on a specific interface. As shown in Figure -6, the Cisco 80 can use timing sources recovered from any one of the LIMs or the external or internal clock. This recovered timing signal is used to generate the transmission clock. The clock source can originate from one of the LIMs, an external clock or internal clock. Figure -6 Timing Selection -

12 Timing Chapter LIM Recoverd clock LIM Recoverd clock LIM 3 Recoverd clock External clock Internal clock Primary Internal clock PLL holdover LIM Recoverd clock LIM Recoverd clock LIM 3 Recoverd clock External clock (in) Internal clock Secondary External clock (in) External clock (out) 5067 The External clock internal input and internal output sources can be used to synchronize the timing of multiple Cisco 80 units. See Figure -7. Figure -7 External clock synchronization External clock source IN OUT IN OUT IN OUT Cisco 80 Cisco 80 Cisco

13 Chapter Specifications Specifications For successful installation of the Cisco 80 unit, it is recommended that reference be made to the technical details in Table - Table - Technical Specifications ATM Line Interface Modules Channels Connection Types Signalling Port capacity LIM type Connector 56 simultaneous 8 bi-directional PVC, with traffic shaping option Transparent to signalling Future release will support UNI 3.0/3./4.0 3 ports: st - user port nd serves only as network port 3 rd may serve as facility protection switch, and user port Hot swappable LIMs OC-3c/STM- MM, SM long and short haul E/T CSM E3/T3 STM- electrical SC for fiber BNC for coax RJ-45 for electrical STM-, CSM, DS Usage Parameter Control Direction Bi-directional and Uni-directional Services CBR, VBR., VBR., VBR.3, UBR Traffic Parameters PCR, SCR, CDV, MBS Counters Low priority cells, High priority cells, GCRA and GCRA non-conforming cells Policing options count only tag to lower priority discard End-to-end QoS Traffic Parameters Cell Loss Ratio Severely Errored Blocks Ratio Cell Delay Variation Cell Transfer Delay Log File 000 events stored in non-volatile memory ATM Data Collection Counters UPC and PM -3

14 Specifications Chapter Table - Technical Specifications (continued) ATM Line Interface Modules Channels Memory size Memory Type LIM Data Collection Counters PM Memory size 56 simultaneous 8 bi-directional Per 56 VCs, 5 minute intervals, 96 history windows Non-volatile Per 56 VCs, 5 minute intervals, 96 history windows Memory Type Non-volatile Shaper Data Collection Counters Statistics counters Memory size 64k cells divided into 3 classes Memory Type DRAM Timing Source Any LIM, External, Internal, holdover Connection External timing input & timing output External Alarms Four External alarm inputs One external alarm dry contact output Management SNMP Agent supports the relevant information provided by: MIB II (RFC 3 and 573), AToM MIB (RFC 695), SONET/SDH MIB (RFC 595), DS3 MIB (RFC 407) and additional private MIBs Access through local terminal using RJ45 on the back panel or remotely through SNMP/Telnet-manager LED Indicators LIM Transmit, Receive, Alarm System Run, Test, Error Mechanical Mounting Rack or desktop Dimension.6 high (.5U) x 7 Wide x 0. deep Weight 4.8 lbs (. kg) Environmental Operating Temp. 3 F to 04 F (0 C to 40 C) Relative Humidity 5% to 95% without condensation Safety Compliance UL, CUL, TUV, FCC EMI/RFI CE, FCC 5 Power AC (Fixed PS) Voltage VAC Auto Ranging ± 0%, 50/60 Hz Max. Current 600 ma -4

15 Chapter Specifications Table - Technical Specifications (continued) ATM Line Interface Modules Power AC (Redundant PS) Power DC (Redundant PS) Channels Voltage Max. Current Voltage Max. Current 56 simultaneous 8 bi-directional 85-40/60-40VAC, 50/60 Hz 700 ma VDC A -5

16 Specifications Chapter -6