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The Catalyst 4000 Access Gateway module integrates IP WAN routing, voice over IP (VoIP), and Cisco Architecture for Voice, Video, and Integrated Data (AVVID) IP Telephony services into a modular multilayer switching platform.
With the Catalyst 4000 family switch and the Access Gateway module, enterprise branch offices can deploy a single box solution for LAN switching and IP WAN routing. By integrating LAN switching and IP WAN routing, the IP WAN router solution reduces network complexity and network administration costs.
The Access Gateway module VoIP solution allows branch offices to connect with the Public Switched Telephone Network (PSTN) and use toll by-pass to reduce toll charges for voice traffic. The VoIP solution establishes seamless communication between the enterprise branch office and corporate headquarters.
Under the control of Cisco CallManager, the Access Gateway module IP Telephony solution can provide voice services such as conferencing and voice transcoding to the branch office. Transcoding represents compression and decompression capabilities. These services were previously available only at corporate headquarters.
This chapter contains these sections:
In a Catalyst 4000 family switch, the Access Gateway module functions as an IOS network device. The Access Gateway module attaches to the Gigabit Ethernet trunk on the backplane of the switch, which can support up to six VLANs.
Figure 1-1 shows a system overview of the the Catalyst 4000 family switch connected to the Access Gateway module by the Gigabit Ethernet 802.1q trunk.
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Note In this illustration, the Access Gateway module is represented by a router icon with a V to indicate routing and voice gateway functions. See Figure 1-3 for an actual representation of the module. |
To manage the physical interfaces in a normal mode of operation, the Access Gateway module provides the following features:
Figure 1-2 shows the Catalyst 4000 family switch and the console port, which is located in the top slot, second port from the right.
Figure 1-3 shows the Access Gateway module with the console port, which is located on the lower left and the Fast Ethernet port, which is located on the lower right.
This section presents an overview of the Access Gateway module applications:
In the IP WAN router application, the Access Gateway module provides the Catalyst 4000 family switch with an integrated switching and routing solution.
In its basic application, the Access Gateway module is an IP WAN router that provides full support for Cisco IOS software features:
Figure 1-4 shows the Access Gateway module in the IP WAN router application.
In the IP WAN router application, the Access Gateway module supports the following features:
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Note Primary Rate Interface (PRI ) dial-up data connections are not supported at this time. |
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Note Digital Signal Processor (DSP) SIMMs are not required in this application. |
In the VoIP gateway and router application, the Access Gateway module provides the Catalyst 4000 family switch with an integrated switching and routing solution plus toll by-pass through H.323v2 voice gateway functions. Toll by-pass allows voice calls to be transported between sites over the IP WAN to save on toll charges. Analog phones and faxes can be connected to the Access Gateway module and traffic directed to the PSTN.
The VoIP gateway and router application requires the Catalyst 4000 Access Gateway module to be configured with the Digital Signal Processor (DSP) SIMMs option and the Cisco IOS IP/H323 Plus feature set. Cisco IOS provides support for the following voice features:
Figure 1-5 shows the Access Gateway module in the VoIP gateway and router application.
In the VoIP gateway and router application, the Access Gateway module provides the Catalyst 4000 family switch with connectivity from analog phones or a Private Branch Exchange (PBX) to the PSTN or an IP WAN.
In the VoIP gateway and router application, the Access Gateway module supports the following features:
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Note Although the Access Gateway module does not support Cisco CallManager or IP Phones in this mode, it requires four DSP SIMMs for processing voice signals. |
Figure 1-6 shows a typical Access Gateway module VoIP gateway and router topology.
In the VoIP gateway and router topology, the Access Gateway module establishes an H.323 peer relationship with other H.323 gateways.
In the IP Telephony and router application, the Access Gateway module provides an integrated switching and routing solution for large branch offices that need to deploy IP Phones and that require integrated local PSTN connectivity and services, such as conferencing and transcoding.
In IP Telephony mode, the Access Gateway module provides network-based voice services (DSP farm) for Cisco CallManager. These voice services include conferencing (both ad-hoc and meet-me) and transcoding between different encoding types. The network-based voice services are under the control of Cisco CallManager and use the Simple Client Control Protocol (SCCP).
IP Telephony mode requires the Catalyst 4000 Access Gateway module to be configured with the DSP SIMMs option and the Cisco IOS IP/H323 Plus feature set.
Figure 1-7 shows the Access Gateway module in the IP Telephony gateway and router application.
In the IP Telephony gateway and router application, the Access Gateway module supports the following features:
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Note The Access Gateway module requires four DSP SIMMs in this mode. |
Figure 1-8 shows Access Gateway module IP Telephony gateway and router topology.
In the IP Telephony gateway and router topology, the Access Gateway module uses:
This section describes the Access Gateway module data and voice interfaces.
| Interface | Encapsulation | Remarks |
|---|---|---|
Fast Ethernet (front panel) | Native only | Process switching only; no IP multicast |
Gigabit Ethernet (backplane) | Native, 802.1q |
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WIC-2A/S | Synchronous support only | |
WIC-1DSU-56K4 | HDLC, PPP, FR |
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VWIC-1MFT-T1 | HDLC, PPP, FR | Channel group |
VWIC-2MFT-T1 | HDLC, PPP, FR | Channel group |
VWIC-2MFT-T1-DI | HDLC, PPP, FR | Channel group |
VWIC-1MFT-E1 | HDLC, PPP, FR | Channel group |
VWIC-2MFT-E1 | HDLC, PPP, FR | Channel group |
VWIC-2MFT-E1-DI | HDLC, PPP, FR | Channel group |
VIC-2BRI-S/T-TE | HDLC, PPP, FR | User side S/T only, no 144 kbps and 80 kbps leased line |
| 1High level Data Link Control 2Point-to-Point Protocol 3Frame Relay |
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Note Primary Rate Interface (PRI ) dial-up data connections are not supported at this time. |
Table 1-2 shows the voice interfaces and signaling that Access Gateway module supports.
| Interface | Signaling | Remarks |
|---|---|---|
VIC-2FXS | Ground start, Loop start | Supports hook-flash and CLID |
VIC-2FXO | Ground start, Loop start | Supports CLID |
VIC-2FXO-EU | Ground start, Loop start | Supports CLID |
VWIC-1MFT-T1 | Supports PRI on user and network sides | |
VWIC-2MFT-T1 | T1-CAS, PRI | Supports PRI on user and network sides |
VWIC-2MFT-T1-DI | T1-CAS, PRI | Supports PRI on user and network sides, no DI |
VWIC-1MFT-E1 | PRI | Supports PRI on user and network sides |
VWIC-2MFT-E1 | PRI | Supports PRI on user and network sides |
VWIC-2MFT-E1-DI | PRI | Supports PRI on user and network sides, no DI |
| 1Trunk Level 1 - Channel Associated Signaling 2Primary Rate Interface |
Posted: Thu Sep 14 18:42:34 PDT 2000
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