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devices tightly integrated with the IP-based phone system is advantageous for increased manageability,
scalability, and cost-effectiveness. The Direct Inward Dialing (DID) port is used to provide off-premises DID
connection from the central office. It serves only incoming calls from the PSTN. The Caller ID feature is not
supported in DID mode.
The following table provides information about Cisco 400 Voice Gateway SKU:
Table 2: Cisco 400 Voice Gateway FXS-E/DID, REN, Failed-over Port Support
Number of Failed-over Ports
RJ-11
Connectors
Maximum Number or RENs
Maximum Number of FXS-E Ports
Interface
2
FXS: 1x2
FXO: 1x2
10
2
VG400-2FXS/2FXO
4
FXS: 1x4
FXO: 1x4
12
4
VG400-4FXS/4FXO
6
FXS: 1x2 1x4
FXO: 1x2 1x4
12
6
VG400-6FXS/6FXO
—
FXS: 1x4 1x4
16
8
VG400-8FXS
Table 3: Slot, bay, and port information for Cisco VG400 FXS Port
Port
Bay
Slot
Interface
0-1
1
0
2FXS/2FXO
0/1/0-1
0-3
1
0
4FXS/4FXO
0/1/0-3
0-5
1
0
6FXS/6FXO
0/1/0-5
0-7
1
0
8FXS
Table 4: Slot, bay, and port information for Cisco VG400 FXO Port
Port
Bay
Slot
Interface
2-3
1
0
2FXS/2FXO 0/1/2-3
3-7
1
0
4FXS/4FXO 0/1/3-7
6-11
1
0
6FXS/6FXO
0/1/6-11
Cisco VG400 Voice Gateway Hardware Installation Guide
6
Introduction to Cisco VG400 Voice Gateway
Slot, Bay, and Ports