Chapter

Cisco MGX 8220 System Overview

Traffic Management

Traffic management is provided by the Cisco MGX 8220 Connection Congestion Management (ACCM) feature. This feature is a virtual source/virtual destination rate-based closed loop feedback scheme between nodes based on ForeSight and the ATM Forum Available Rate specification. Periodically the round trip delay (RTD) of a cell to the far end and back is calculated for each actual connection. The RTD is used to determine how frequently the ForeSight rate adjustment cells are sent to the far end. Based on available bandwidth and current access rate, every few microseconds a ForeSight cell is transmitted to the far end with any rate adjustments that are necessary to make better use of the available bandwidth (rate is adjusted up, down, or fast down). The Cisco MGX 8220 MIB includes rate (MIR, PIR, and QIR) and adjustment (up%, down%, and fast-down%) objects.

ATM Local Management Interface

ATM local management interface (ATM LMI) operates between the Cisco MGX 8220 shelf and the Cisco BPX 8600 series. The ATM LMI is used to communicate change of status of semi-permanent connections. The ATM LMI protocol conforms to the protocol specified in ITU-TS Recommendation Q.2931, Sept. 1994. The ATM LMI also supports optional proprietary extensions to the ATM LMI for the reporting of node information and BNI queue configurations.

The two end points of the ATM LMI signaling are an ATM LMI process in the BCC in the Cisco BPX 8600 series and an ATM LMI process in the ASC in the Cisco MGX 8220 shelf. The ATM LMI PDUs are transported over an AAL5 connection (VPI=3/VCI=31) between the BNI on the Cisco BPX 8600 series side and the BNM on the Cisco MGX 8220 side. The ATM LMI process in the Cisco BPX 8600 series can support ATM LMI connections for up to 16 Cisco MGX 8220 shelves.

The Cisco ATM LMI extension (which must be specifically enabled) uses a node update status message, which is sent (Cisco BPX 8600 to Cisco MGX 8220 shelf or Cisco MGX 8220 shelf to Cisco BPX 8600) whenever a change in node name, node IP address, major alarm status, or minor alarm status occurs.

The message can optionally contain Qbin status, thereby allowing Cisco MGX 8220 to configure the BNI port egress queues.

Cisco MGX 8220 Shelf

Physically, the Cisco MGX 8220 shelf consists of cards in a 19-inch rack-mounted shelf.

The shelf can be powered either from a -48V DC source or from a 220–240V AC source. The DC version includes DC power entry modules that can be mounted in the shelf. The AC version requires an external rack-mounted, AC power module. Both versions require a rack-mounted cooling assembly. Multiple Cisco MGX 8220 shelves can be mounted in the same rack sharing power and cooling assemblies. For more information on the shelf and power options, see Chapter 2, “Common Equipment Description.”

The Cisco MGX 8220 shelf contains 16 slots. Each slot can accommodate a front card and a back card. Six slots are reserved for common equipment modules. The common equipment modules are the core modules required for the system to operate. Service modules (SMs) occupy the other 10 slots and provide communication and transfer capability.

The front row of the shelf is used for function modules. These cards perform the more complex functions within the unit (for example, Frame Relay to ATM conversion).

The back row is used for line modules. These cards provide interfaces to one or more transmission lines connected to the Cisco MGX 8220 shelf (for example, the trunk line to the Cisco BPX switch or an RS-232 line to a control terminal).

 

 

Cisco MGX 8220 Installation and Configuration

 

 

 

 

 

 

 

Release 5.0, Part Number 78-6430-03 Rev. D0, November 2003

 

 

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Cisco Systems manual Traffic Management, ATM Local Management Interface, Cisco MGX 8220 Shelf
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MGX 8220 specifications

The Cisco Systems MGX 8220 is a versatile, high-performance media gateway that has become an integral component in the telecommunications infrastructure. Designed to facilitate the transition from traditional circuit-switched networks to advanced packet-switched environments, the MGX 8220 supports a wide array of voice, video, and data services, making it an essential tool for service providers and enterprises seeking to enhance their network capabilities.

One of the key features of the MGX 8220 is its robust signaling and media processing capabilities. Equipped with support for both Voice over IP (VoIP) and traditional telephony protocols, this gateway enables seamless integration of different communication formats. It boasts a modular architecture, which allows for the addition or removal of various line cards to meet changing demands and technology advancements. This modularity provides operators with the flexibility to scale their services without significant overhauls to their existing infrastructure.

The MGX 8220 is capable of delivering high-density media handling for a multitude of services. With its support for ATM and IP networks, the gateway can handle TDM (Time-Division Multiplexing) to packet voice conversions efficiently. It is designed to optimize network resources by dynamically allocating bandwidth based on traffic requirements, thus ensuring efficient use of network resources and improved performance.

Another significant characteristic of the MGX 8220 is its enhanced quality of service (QoS) features. This capability ensures that voice and video traffic is prioritized appropriately, minimizing latency and jitter while maximizing overall call quality. By employing sophisticated traffic management techniques, the MGX 8220 can deliver a superior user experience, which is critical for any service provider aiming to offer competitive communication solutions.

Furthermore, the gateway includes built-in security features to protect against unauthorized access and ensure the integrity of sensitive data. This includes encryption for voice and video transmission, as well as support for secure signaling protocols.

Overall, the Cisco Systems MGX 8220 stands out as a comprehensive media gateway solution, providing essential functionalities for modern communication needs. Its combination of modularity, high-density processing, effective QoS management, and security features makes it a compelling choice for organizations looking to modernize their telecommunications infrastructure while ensuring reliability and performance. As businesses continue to evolve and demand more from their networks, the MGX 8220 offers a pathway to future-ready communications.
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