This chapter provides a broad description of the MGX 8260 media gateway. It describes MGX 8260 architecture, components, features and functions.
Product Description
The Cisco MGX 8260 is a high-density, carrier-class gateway that provides the flexibility to offload TDM and VoIP traffic across a range of interfaces and backbone network.
Provisioning and Management
The MGX 8260 media gateway offers flexible ways to manage, provision, and monitor services. Several network management options are supported:
Simple Network Management Protocol (SNMP)
Command Line Interface (CLI)
Optional MGX 8260 WebViewer graphical user interface
Optional Cisco Media Gateway Manager (CMGM)
SNMP supports the integration of the MGX 8260 with existing network management system (NMS), provisioning, and operations support system (OSS) platforms. All system attributes are accessible through SNMP, including generating trap messages to an event collector.
All MGX 8260 functions and features are available at the command line interface. During initial system configuration you can only use the command line interface via the console port. The CLI supports management via telnet sessions. Some configuration tasks can only be performed from the command line interface.
WebViewer allows ready access to dedicated MGX 8260 gateway information, including authorization, configuration, connections, tests (loopbacks, continuity test [COT] bit error rate test [BERT]), performance monitoring, and administration functions.
Cisco Media Gateway Manager (CMGM) is the optional element management system (EMS) for the MGX 8260. CMGM can deploy, configure, and manage multiple MGX 8260 media gateways in one or more Points of Presence (POPs), providing a single interface for fault, configuration, performance, and security management. CMGM operates within the Cisco Element Management Framework (CEMF) to provide chassis and sub-chassis component management for MGX 8260 via a graphical user interface (GUI).
The MGX 8260 gateway offers multiple levels of security access, including viewing, configuration, system administration, and super-user control. It also supports backup and restore of the node configuration database, as well as downloadable software updates and upgrades. WebViewer provides complete browser access for system monitoring and configuration, as well as for reporting events through electronic mail or paging systems.
Redundancy
MGX 8260 media gateway supports redundant operation for all circuit cards as well as the primary power feeds. The MGX 8260 uses mirrored (1:1) redundancy for its System Control Cards (SCCs), Distribution Matrix Cards (DMCs) and Broadband Service Cards (BSCs). The Narrowband Service Cards (NSCs) implement one-to-many (1:N) redundancy, with one secondary NSC providing redundant protection for multiple primary NSCs. The power subsystem accepts two separate input feeds, with each feed sized to handle the entire electrical load of the media gateway.
Troubleshooting Tools
Because the MGX 8260 gateway embeds all the most common forms of line isolation tools, you can provide rapid turn-up and service installation for customers. A battery of line-testing capabilities includes COT (4-wire Continuity Test), Test Line 100, 102, and 108, plus transmission line loopbacks and Bit Error Rate Test (BERT) capabilities.
Solution Applications
Based on the Cisco Open Packet Telephony framework, the MGX 8260 ensures interoperability with existing technology (TDM) while enabling high scalability and a smooth transition to emerging value-added services. In the Open Packet Telephony framework, an industry-standard open interface separates the call control layer from the switching fabric. This open interface enables the MGX 8260 to integrate with operations support systems, service creation environments, and media gateway controllers using the media gateway control protocol (MGCP).
Service providers who deliver Internet dial access traffic to ISPs are feeling the strain of rapidly increasing demand for Internet services. As data traffic increases, existing time-TDM voice networks are fast becoming congested. Legacy TDM networks were not designed to handle the volumes, hold times or traffic patterns of Internet dial access traffic.
Carriers can groom traffic at the point of interconnect and switch modem traffic via ISDN primary rate interface (PRI) to ISP network access servers (NASs), while sending voice traffic over SS7 inter-machine trunks (IMTs) to existing circuit switches or other networks. (See Figure 1-1.) By offloading data traffic, switch congestion is eliminated and the carrier's existing voice switch is used for its original purpose—handling voice traffic efficiently.
Cisco Internet PRI offload solutions deliver intelligent call routing on a call-by-call basis, enabling the platforms to double as a multiservice gateway. The MGX 8260 delivers high-performance service switching intelligence in the platform, providing TDM-to-TDM (voice, off net), TDM-to-VoIP, and TDM-to-PRI (data) switching.
Figure 1-1 MGX 8260 Internet PRI Offload Solution
Troubleshooting
The operation of the MGX 8260 system depends on the interoperability of its components with external devices and services.Configuration database entries in the components must reflect actual interface parameters within and among the components.
The hierarchy of anticipated faults likely to affect media gateway operation is as follows:
Erroneous database entries
Media gateway—card configuration, PSTN interface parameters, IP parameters
Media gateway controller (call agent)—trunk configuration, routing, call detail record (CDR) format
SS7 subsystem—link provisioning and configuration, circuit group parameters
Communication protocols—IP addresses, Ethernet configuration, IPDC/MGCP call control parameters, access passwords
External Interfaces
Console/modem interfaces
Ethernet management ports (dedicated and virtual ports)
MGX 8260 to call agent control interface
MGX 8260 interface to/from carriers via PSTN
Fast Ethernet and OC-3 interfaces
Software bugs
Component failure
The general procedure for isolating faults in the system includes:
Obtaining a detailed description of the problem, the actions leading to the discovery of the problem, its symptoms, date/time of occurrence and repeatability.
Reviewing system logs to identify process problems affecting interprocess communication, incoming/outgoing seizures, signaling errors or component failures.
Verifying database entries affecting the call flow associated with the problem.
Observing status LEDs on system components to reveal possible component or interface failures.
Contacting Cisco TAC for additional assistance in isolating the fault.
Downloading software patches.
Removing and replacing faulty hardware components.
The MGX 8260 consists of hardware and software components contained in a rack-mountable, mid-plane chassis. The multiple bus architecture uses an internal ATM cell switch to rapidly move data across TDM, ATM and IP interfaces. (See Figure 1-2.)
Features
Release 1.2 of the MGX 8260 switch application software supports the following features:
Circuit switching (TDM to TDM, TDM to VoIP) or hairpinning within the node
Channelized DS1 (T1/E1), DS3 (T3) with primary rate interface (PRI), non-facility associated signaling (NFAS) support to 100BaseT, Fast Ethernet links.
IPDC call control via a soft switch server
MGCP call agent control with PRI backhaul over Reliable User Data Protocol (RUDP)
128ms echo cancellation (EC)
DTMF, MF tone detection/generation
Continuity test (COT), Test Line Access
Multi-tier redundancy
Graceful hardware and software updates and upgrade
SNMP and embedded Web-based (HTML) node management
Support for G.711, G.726, and G.729a codecs
Voice Activity Detection (VAD) with silence suppression
Comfort noise generation (CNG)
Real time conferencing protocol (RTCP)
Multi-chassis configurations for VoATM via OC-3 SONET connections to appropriately equipped MGX 8850 gateways
Support for Cisco Media Gateway Manager (CMGM) within the Cisco Element Management Framework (CEMF) graphical user interface (GUI)
For more detailed information on components of the MGX 8260 system, refer to Chapter 2.
Hardware Components
All circuit cards mount in a 16-slot chassis with a midplane structure. (See Figure 1-3.) Front cards incorporate status LED indicators reflecting interface activities. Back cards contain the physical connection points for DS1, DS3, Ethernet, OC-3, and serial interfaces.
Chassis
Dual -48VDC power feeds; power converters contained on each circuit card
(16) slots [front and rear]; (14) single width, (2) double width
(3) slide-out fan trays; plenum to redirect air flow from top to rear of chassis
All circuit cards and fan modules are hot-swappable
Alarm relays driven through DB15 connector
Multi-tier redundancy—circuit cards, system buses and power feeds
Designed to be mounted in a 19" or 23" rack, using universal rack mount ears
NEBS Level 3 certified
Figure 1-2 MGX 8260 Architecture
Figure 1-3 MGX 8260 Chassis—Front View
1
Fan trays (behind access panel)
2
Narrowband Service Cards (NSCs)
3
System Control Cards (SCCs)
4
Distribution Matrix Cards (DMCs)
5
Broadband Service Cards (BSCs)
6
Air intake
7
Rack mounting ears (19-inch shown)
Circuit Cards
MGX 8260 circuit cards include a system controller, service cards and associated interface cards. Refer to Table 1-1 and Table 1-2 for circuit card descriptions. Table 1-3 lists the chassis slots and allowable card locations.
Table 1-1 Front Cards
Type
Description
Redundancy1
Back Card Interfaces
BSC
Broadband Service Card
1:1
(6) DS3 [SMB]
DMC
Distribution Matrix Card
1:1 (mated with SCCs)
(6) DS3 [SMB]
NSC
Narrowband Service Card
1:N
(16) DS1 [RJ21-T1, RJ48-E1]2or
Redundant back card or
No back card (DSP farm)3
SCC
System Control Card
SCC-FE (100BaseT ports)
SCC-OC-3
1:1
(2) 10BaseT Ethernet [RJ45]
(2) RS-232 serial [DB9]
(1) BITS clock [RJ45]
(4) 100BaseT [RJ45] or
(4) OC-3 [single mode LC]
1. 1:1 = one-to-one redundancy using two identically configured cards; 1:N = one-to-many redundancy with one card designated the secondary card for all other primary cards.
2. Base software supports G.711 codec with voice activity detection (VAD) and echo cancellation.
3. NSC-DSP cards are required when voice compression software is purchased (G.726 and G.729a codecs).
Table 1-2 Back Cards
Type
Front Card
Description
OC-3SMIBC
SCC
(4) OC-3 single mode intermediate reach fiber (used for interconnecting multiple MGX 8850s equipped with PXM45 and AXSM blades)
SCCBC-4FE
SCC
(4) 100BaseT Fast Ethernet ports
T1E1BC-50NR
NSC
(16) T1/E1, 100-ohm interfaces via (2) 50-pin RJ21 connectors, one RX Tip & Ring, one TX Tip and Ring
T1E1BC-RED
NSC
Supports 1:N redundant NSC configurations when primary cards are equipped T1E1BC-50NR or T1E1BC-RJ48 back cards
T1E1BC-RJ48
NSC
(16) E1, 120-ohm interfaces via individual RJ48C jacks; 75-ohm impedance requires 120-ohm to 75-ohm balun adapter
T3E3BC-6DSX
BSC, DMC
(6) DS3 interfaces (separate transmit and receive) via 12 SMB female coaxial connectors
Table 1-3 Circuit Card Slot Locations
Slot
Card Type
Notations, Restrictions
1
NSC
For trunk interfaces use a T1, E1 or redundant1 back card. For NSC-DSP applications, a blank plate covers the back card slot.
2
NSC
For trunk interfaces use a T1, E1 or redundant1 back card. For NSC-DSP applications, a blank plate covers the back card slot.
3
NSC
For trunk interfaces use a T1, E1 or redundant1 back card. For NSC-DSP applications, a blank plate covers the back card slot.
4
NSC
For trunk interfaces use a T1, E1 or redundant1 back card. For NSC-DSP applications, a blank plate covers the back card slot.
5
NSC
For trunk interfaces use a T1, E1 or redundant1 back card. For NSC-DSP applications, a blank plate covers the back card slot.
6
NSC
For trunk interfaces use a T1, E1 or redundant1 back card. For NSC-DSP applications, a blank plate covers the back card slot.
7
NSC, DMC
For NSC trunk interfaces use a T1, E1 or redundant1 back card. For NSC-DSP applications, a blank plate covers back card slot. For DMC trunk interface use a T3E3BC-6DSX back card; an SCC must be in slot 9.
8
NSC, DMC
For NSC trunk interfaces use a T1, E1 or redundant1 back card. For NSC-DSP applications, a blank plate covers back card slot. For DMC trunk interface use a T3E3BC-6DSX back card; an SCC must be in slot 10.
9
SCC
For VoIP applications with an SCC-FE, use an SCCBC-4FE back card. For VoATM applications with an SCC-OC-3, use an OC-3SMIBC back card.
10
SCC
For VoIP applications with an SCC-FE, use an SCCBC-4FE back card. For VoATM applications with an SCC-OC-3, use an OC-3SMIBC back card.
11
BSC, NSC
BSC requires a T3E3BC-6DSX back card. For NSC trunk interfaces use a T1, E1 or redundant1 back card. For NSC-DSP applications, a blank plate covers back card slot.
12
BSC, NSC
BSC requires a T3E3BC-6DSX back card. For NSC trunk interfaces use a T1, E1 or redundant1 back card. For NSC-DSP applications, a blank plate covers back card slot.
13
BSC, NSC
BSC requires a T3E3BC-6DSX back card. For NSC trunk interfaces use a T1, E1 or redundant1 back card. For NSC-DSP applications, a blank plate covers back card slot.
14
BSC, NSC
BSC requires a T3E3BC-6DSX back card. For NSC trunk interfaces use a T1, E1 or redundant1 back card. For NSC-DSP applications, a blank plate covers back card slot.
15
BSC, NSC
BSC requires a T3E3BC-6DSX back card. For NSC trunk interfaces use a T1, E1 or redundant1 back card. For NSC-DSP applications, a blank plate covers back card slot.
16
BSC, NSC
BSC requires a T3E3BC-6DSX back card. For NSC trunk interfaces use a T1, E1 or redundant1 back card. For NSC-DSP applications, a blank plate covers back card slot.
1. Only one T1E1BC-RED back card can be equipped in an MGX 8260 chassis.
Bus Structures
The MGX 8260 employs three types of buses within the midplane:
Switch Bus—dedicated, high speed (622Mbps) bus handles internal MGX 8260 remote procedure call (MRPC) messaging among circuit cards.
Cell Bus—handles internal asynchronous transfer mode (ATM) data cell among (48-byte octets) among circuit cards. Each circuit card incorporates the segmentation and reassembly (SAR) circuitry to receive and transmit ATM data cells. [AAL5 = ATM Adaptation Layer 5]
TDM Bus—handles circuit switched data transfers between BSCs, DMCs and NSCs.
Each bus structure is electrically redundant with bus transfers controlled by the currently active SCC.
Scalability
A single MGX 8260 chassis can be provisioned to support up to 27,264 DS0s in a TDM-to-TDM configuration as shown in Table 1-4. The number of VoIP sessions varies based on the type of codecs and quantity of available NSC-DSP ports as shown in Table 1-5.
Note As of MGX 8260 software release 1.4, Cisco no longer supports voice over IP (VoIP) functionality
for the MGX 8260.
Software Components
The MGX 8260 software architecture is based on centralized control within a distributed processing environment. The SCC provides centralized control by storing the software images for all cards and using internal messaging to dynamically update the configuration database of each card. Each service card contains a sufficient number of digital signal processors (DSPs) to run the algorithms controlling local interfaces, bus switching, resource management and support services (codec translation, DTMF/MF tone detection, VAD, CNG, etc.).
Client-Server Applications
Figure 1-4 shows a high level view of the distributed processing environment within the MGX 8260. Node control including application downloading resides in the SCC. Various application programs run on each circuit card. Some of the programs launch as servers which support client applications running on other circuit cards. The Switch Bus carries messages across all circuit cards. The Cell Bus processes data transfers.
The ATM applications running on service cards include the following components:
CP—control point
SAR—segmentation and reassembly module (parses data into 48-byte octets for transfer over the Cell Bus)
DSE—data service engine
Figure 1-4 MGX 8260 Software Architecture
Software Functional Groupings
Figure 1-5 shows with finer granularity the types of applications running within the MGX 8260 software architecture. Figure 1-6 indicates how various software components fit into the layered software architecture.
For maintenance purposes these components are categorized as follows.
System (VxWorks) Support Group—uses a system interface wrapper (SIW) to interface with VxWork's services.
System Resources
Aal1gator (AAL1) resource for data path creation and end channel number (ECN) allocation
SCC BIM resource allocates ECNs for Fast Ethernet and OC-3 connections
Inter-card Communication Group—handles MGX 8260 remote procedure call (MRPC) messaging among circuit cards.
Call Setup Group—includes the following modules:
MGCP protocol processing (MSCP)
MGCP platform control (MPC)
Platform call control (PCC) and platform resource control (PRC)
Resource manager (RMG)
ISDN backhaul protocol (IBP)
Database Management Group—includes the following modules:
Database manager (DBM)
DBM sync (DBMSYNC)
Upgrade/downgrade
File management (FM)
Shelf/Card Management Group—includes the following modules:
Shelf manager (SM)
Card manager (CM)
Core card redundancy (CRM)
Service card redundancy
Driver Group—includes the following modules:
Switch fabric (ASX)
ALM, ALBM
Ethernet broadband interface module (BIM)
Cell Bus (CBT)
SAR
Environmental monitoring (EMM)
Clock switch nodule (CSM)
Alarm/Trap/Event Handler Group—includes the following modules:
Alarm (ALARM)
Event logging (LOGD)
Trap manager (TRAP)
Error handler
SNMP/MIB/CLI Group—includes the following modules:
SNMP agent (SNMP)
Web manager (WEB)
Command line interface (CLI)
Figure 1-5 MGX 8260 Software Components
Figure 1-6 MGX 8260 Software Layering
DSP Features
The following features run as algorithms on DSP farms contained on NSCs:
G.711 codec processing (PCM - 64 kbps)
G.726 codec processing (ADPCM - 32 kbps)
G.729a codec processing (CSCELP - 8 kbps)
Echo cancellation (G.165/G.168, 32 to 128ms tail in 32ms increments)
Dynamic dejitter
Announcement playouts (.au or .wav files)
Test line with tone detect (100, 102 and 108)
Voice activity detection (VAD) with silence suppression and comfort noise generation (CNG)
Each NSC offers 480 DS0 channels for echo cancellation (ecan) and test line support; a maximum of 5,376 DS0 channels are available for such services per MGX 8260 node. The DS0s form a resource pool for "groomer" applications.
Redundancy
Redundancy refers to how components are configured to prevent the loss of service should a system component fail. The MGX 8260 uses mirrored or one-to-one (1:1) redundancy for its SCCs, DMCs and BSCs. The NSCs implement one-to-many (1:N) redundancy, with one secondary NSC providing redundant protection for multiple primary NSCs.
The midplane between cards incorporates redundant switch, cell and TDM busses for data transport and control.
The power subsystem accepts two separate input feeds, with each feed sized to handle the entire electrical load of the media gateway.
An MGX 8260 media gateway is interoperable at various levels with other components in a service provider's network. The extent of network supported services is briefly outlined below. For additional information refer to the following publications
Cisco Element Manager Framework Installation and Administration Guide
Platform Control
Platform control refers to the protocols used by a call agent to process calls through media gateways. Call agents or media gateway controllers (MGCs) establish, maintain and disconnect calls across an IP network.
The following types of MGC protocols are supported by the MGX 8260:
IPDC (Internet Protocol Device Control) is one of the earliest protocols developed to support control of media gateways by external intelligence (soft switch).
MGCP (Media Gateway Control Protocol) evolved from the fusion of IPDC with SGCP (Simple Gateway Control Protocol). MGCP revolves around the creation, maintenance and teardown of endpoints and connections over multiple types of bearer networks. Bearer networks encompass TDM, VoIP and VoATM. An MGCP-based media gateway controller is often referred to as a call agent.
TDM Circuit Switching
An MGX 8260 media gateway interfaces with multiple types of digital trunking and signaling services. The default G.711 codec creates 64 kbps, pulse code modulation (PCM) DS0 channels. The DS0s are multiplexed into DS1 (T1/E1) and DS3 inter-machine trunks with configurable framing and signaling parameters.
Optional support is available for SS7 signaling via ISDN PRI with bearer and data channel structures for T1 and E1 trunk types. D channels may be configured to control bearer channels on more than one trunk (NFAS). Platform control of call setup of TDM calls is accomplished via Q.921/Q.931 messaging "tunneled" within MGCP commands and notifications.
VoATM
The MGX 8260 is an ATM switch at its core and is thus ideally suited for VoATM applications. With the SCC equipped with the OC-3 back card, an MGX 8260 node supports synchronized optical network (SONET) connections to multiple MGX 8850 chassis.
The Cisco MGX 8850 IP + ATM multiservice switch is designed for service providers deploying narrowband and/or broadband services. The MGX 8850 scales from DS0 to OC48c and supports any combination of the following services:
Frame relay
ATM
VoATM
VoIP
Circuit emulation
IP
Wireless aggregation
DSL aggregation
ATM service backbones
Virtual Private Networks (VPNs)
When used in a multi-chassis deployment with an MGX 8260 gateway, each MGX 8850 must be equipped with the AXSM-16-155 ATM switch service module. This module supports an OC-3 fiber interface at 155Mbps. Fro VoIP and VoATM applications the MGX 8850 must also be equipped with the Voice Interworking Service Module (VISM). The VISM provides toll-quality voice, fax and modem transmission and efficient utilization of wide-area bandwidth through industry standard implementations of echo cancellation, voice-compression and silence-suppression techniques.
For VoATM via SONET the MGX 8260 supports a maximum of 1,986 calls per second (cps) over each OC-3 fiber link or 7,944 cps over all four OC-3 links.
Element Management
The MGX 8260 incorporates a number of components to support element management of the media gateway node. (See Figure 1-7.) Management features are categorized as follows:
Configuration (lines, ports)
Performance (real-time monitoring)
Faults (traps, alarms)
Accounting (call statistics, billing)
Security (access control)
You can manage the MGX 8260 from any of the following interfaces:
SNMP Management Information Base (MIB)
Command Line Interface (CLI)
WebViewer (MGX 8260 option)
The MGX 8260 gateway offers multiple levels of security access, including viewing, configuration, system administration, and super-user control. It also supports configuration file backup and restore, as well as software upgrades.
SNMP MIBs
With SNMP you can integrate the MGX 8260 with existing NMS management, provisioning, and Operations Support Systems. All system attributes are accessible through SNMP, and the MGX 8260 generates trap messages to an event collector.
An SNMP manager can perform the following operations:
Configuration
Alarm management
Statistics generation
Diagnosis
Real-time monitoring
Viewing network map
Managing traps
MGX 8260 SNMP MIBs are based on industry standard and proprietary needs. Standard MIBs comply with IEFT RFC1406, 1407, 1595, 1213, etc. Enterprise MIBs can be constructed using CLI syntax definitions, for example voicePortTable, cardTable, emailRegTable, etc.
Command Line Interface
The CLI is an API-based interface which incorporates on-line help. The CLI is essential for establishing initial configurations. It is also the primary means for remote management via telnet sessions. All MGX 8260 functions, including SNMP MIBs, are available at the command line interface. During initial system configuration you can only use the command line interface via the serial console port. Some configuration tasks can only be performed from the command line interface.
Access to the CLI requires a user name and password. The username/password combination governs the degree of access granted to the user. For additional information refer to Appendix A.
WebViewer
The Cisco WebViewer has an intuitive interface that facilitates managing the MGX 8260 from a UNIX or Windows workstation with a Java-enabled Web browser. It provides a real-time display of integrated system alarm, power, card and line status, as well as hot links to cards and lines for detailed configuration information. The WebViewer displays both physical and logical card numbers for redundancy management.
The Cisco WebViewer allows you to perform the following tasks:
Manage nodes and services including system settings, node configurations, service provisioning, and system test features. The Cisco WebViewer accesses information from the SNMP core, but presents it in extended text and graphic forms that simplify working with it.
Monitor the MGX 8260 status and alarms. Every WebViewer screen has a prominent alarm indicator that shows the current operational status. With a single click, users can obtain detailed information on outstanding alarms and events. The MGX 8260 can be configured to notify users by email when alarms or events occur.
Monitor performance. The Cisco WebViewer reports current and historical performance data, and displays performance statistics when performance drops below user-defined levels.
Enforce security. The MGX 8260 enforces security with user accounts and access levels. Users must log onto the MGX 8260 before performing any task; authenticated users can perform only those tasks permitted by their access level. The MGX 8260 supports up to 20 user accounts, each with access privileges ranging from full control to limited guest privileges.
Maintain the system. Using the alarm and test features, maintenance personnel can often diagnose and solve equipment problems directly from the Cisco WebViewer. For example, if a DS1 line raises a performance alarm, maintenance personnel can diagnose the problem with loopbacks, continuity tests (COT), and bit error rate tests (BERTs) and initiate corrective action.
Figure 1-7 MGX 8260 Node Management Architecture
Cisco Media Gateway Manager
The Cisco Media Gateway Manager (CMGM) can deploy, configure, and manage a group of Release 1.2 Cisco MGX 8260 media gateways in one or more points of presence (POP). CMGM also operates as an element management system (EMS). As such, CMGM manages a subnetwork of homogenous network elements.
CMGM includes a graphical user interface that displays network information and supports device management. This interface extends the capabilities of the Cisco Element Management Framework (CEMF) to include managing MGX 8260 media gateways.
CMGM includes links to two management tools, the Cisco WebViewer and the MGX 8260 command line interface, from which you configure individual nodes.
Network management layer applications can communicate with CMGM through an optional Common Object Request Broker Architecture (CORBA) interface provided by the Cisco Voice CORBA Gateway (Cisco VCG). This gateway is a separate product that extends the capabilities of the CMGM product.
CMGM supports four of the five major open system interface (OSI) system management functional areas—fault, configuration, performance, and security.
Fault management—using CMGM, you can monitor the network for faults and clear alarms. The system displays alarm and events on a color-coded topology map. It forwards traps to remote SNMP managers and optionally propagates alarms to higher-level managers (requires the Cisco VCG option).
Configuration management—provides the following configuration management features:
Topological views of network elements
Automatic discovery of Cisco MGX 8260 media gateways
Synchronization of CMGM objects with sub-chassis components
Multi-chassis download of software images
Configuration of SNMP v1 community strings
Menu-launched WebViewer or telnet sessions for web-based or CLI device management
An optional extension, the Cisco VCG, provides a programmatic interface from which higher-level managers can fully configure and monitor theMGX 8260 media gateways.
Performance management—includes the following tools:
Optional menu-launched WebViewer displays performance statistics and real-time counters for all DS1, DS3, and SONET lines. Also, you can adjust the counter thresholds to refine performance collection criteria.
Optional Cisco VCG propagates performance statistics to higher-level managers. On request, CMGM retrieves performance statistics from designated MGX 8260 media gateways, packages the statistics in a bulk file, and forwards it to the manager.
Security Management—uses the mechanisms of CEMF, which authenticates users based on usernames and passwords. When using the Cisco WebViewer or CLI management interfaces, the MGX 8260 also authenticates users based on user account profiles. Both systems support security profiles that define access rights for typical users, from administrators to guests. Messages between CMGM and network elements are secured via SNMP community strings.
Administrative Access
The MGX 8260 supports administrative access by the following methods:
Serial console port using CLI
Modem port using CLI (requires an external modem)
LAN management port via telnet to the CLI or WebViewer
Fast Ethernet in-band management (virtual port) via telnet to the CLI or WebViewer
All access methods require a username and password before access is granted. The username determines the level of administrative privileges available to the user during a management session.
