IBM SG24-4817-00 manual STS-3c Limitations, STM-1 Limitations

This soft copy for use by IBM employees only.

4.4ATM 2-Port 155 Mbps Flexible Media Module and ATM 3-Port 155 Mbps LAN Concentration Module

The ATM 2-Port 155 Mbps Flexible Media Module and the ATM 3-Port 155 Mbps LAN Concentration Module are single-slot concentrator modules that are ideal for high-speed connections to both local resources and to devices up to 20 Km away. They have the following characteristics in common:

•Provide two or three ports, each capable of supporting a 155 Mbps

(full-duplex) connection to either a user, a server, or another switch. The traffic received from these ports will be multiplexed into the backplane connection between the ATM 155 Mbps Media Module and the

switch-on-a-chip.

Each port can support any of the following I/O cards:

Table 3.	ATM 155 Mbps Media Module Supported I/O Cards
Feature		Part Number	Interface	Cable
8800		58G9667	SC	Multi-Mode Fiber
8801		58G9855	SC	Single-Mode Fiber
8802		58G9856	RJ-45	UTP5/STP
8803		58G9857	DB9	STP

•Support either SONET STS-3C or SDH STM-1 on any port at speeds of 155.520 Mbps.

STS-3c Limitations

The STS-3c implementation is a Lite implementation, which, although fully compliant with ATM Forum standards, is lacking some of the management and overhead portions of a full SONET implementation. It will interoperate with the 1-port OC3 I/O card (SMF) and the 1-port OC3 I/O card (MMF) that are installed in an ATM WAN Module. However, neither the 1-port ATM 155 Mbps Single-mode Fiber I/O card nor the

1-port ATM 155 Mbps UTP/STP I/O card (RJ-45) are suitable for direct connection to a public bearer service other than dark fiber. In addition, there may be incompatibilities with certain adapters that expect a full SONET implementation.

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STM-1 Limitations

The STM-1 implementation is a Lite implementation, lacking some of the management and overhead portions of a full SDH implementation. It will interoperate with the 1-port STM1 I/O card (SMF) and the 1-port STM1 I/O card (MMF) that are installed in an ATM WAN Module. However, neither the 1-port ATM 155 Mbps Single-mode Fiber I/O card nor the 1-port ATM 155 Mbps UTP/STP I/O card (RJ-45) are suitable for direct connection to a public bearer service. In addition, there may be incompatibilities with certain adapters that expect a full SDH implementation.

Please refer to Asynchronous Transfer Mode (ATM): Technical Overview for more information on the SONET and SDH standards.

Hot-pluggable in any slot in the 8285 Expansion Chassis.

Support UNI, SSI, and NNI on either port in any combination.

42ATM Workgroup Solutions: Implementing the 8285 ATM Switch