Polycom DOC2237A manual ATM Network Interface Module, ATM-25 and ATM-155 Network Interface Module

Chapter 4 - Hardware Description

ATM Network Interface Module

The ATM Network Interface Module provides the interface between the MGC unit and ATM network. The ATM card may be shipped in two configurations: ATM-25 Network Interface Module that supports one 25MB connection using RJ-45 connector and ATM-155 Network Interface Module that supports one 155MB connection using a fiber optics connector.

The ATM-25 (FVC) Network Interface Module supports up to 10 H.321 endpoints at 2B or 384 Kbps, using First Virtual (FVC) technology.

The ATM-155 (FVC) Network Interface Module supports up to 20 H.321 endpoints at 2B or 384 Kbps, using First Virtual (FVC) technology.

The ATM-25 Network Interface Module is used with the IO-25 card and the ATM-155 Network Interface Module is used with the IO-155 card.

Figure 4-17 shows the architecture for the ATM Network Interface Module. The card architecture is identical to both card types.

ATM								TDM Interface
	ATM Hardware
					MVIP		ATM-MVIP Card
						ISA Interface
		Front
		Panel	Watch							Card	Memory
		LEDs
				Dog					Manager

HDLC Interface

Figure 4-18: ATM-25 and ATM-155 Network Interface Module

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