Zhone Technologies 900, 800, 600 manual Call Routing, Calls Originating from an HSU Port

ISDN-PRI Card Introduction

Figure 5-5shows how the system overcomes these disadvantages. Note that the configuration in Figure 5-5is identical to the one in Figure 5-3.

Figure 5-5highlights the ability of the system to be able to set the protocol between network side and user side for each D channel it uses. Since the PBX can only run the user side protocol, the system must run the network side protocol on the D channel connected to the PBX. However, on the D channels connected to the carrier switches, the system must run the user side protocol.

Carrier A		Carrier B
ISDN Switch		ISDN Switch
Network Side	Network Side
23B+D		23B+D
User Side		User Side
		NFAS 47B+D
	IAD	ISDN PBX
	Network Side	User Side

Figure 5-5. Network and User Side Protocols

5.1.3Call Routing

The system can be simultaneously connected to several network and user side ISDN PRI facilities and to a user’s data terminal equipment (DTE) such as a video codec or a LAN router. The DTE is typically connected through one or more of the system’s HSU cards.

5.1.3.1Calls Originating from an HSU Port

Any call originating from an HSU port must be associated with a call profile (see Call Profiles section). The call profile specifies which D channel is to carry the call. The system will always route an outgoing HSU call to B channels controlled by the D channel specified in the call profile. If no B channels are available, the call will not be placed.

Server Cards 5-7