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Cisco AS5850 Universal Gateway Hardware Installation Guide
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Chapter1 Cisco AS5850 Product Overview
Functional Overview
A dial wholesale customer can connect to a Cisco AS5850, then tunnel PPP (Point-to-Point Protocol)
packet information to a retail service provider using dial Virtual Private Network (dial VPN).
For detailed system specification tables, refer to Appendix A, “Cisco AS5850 Specifications.”
Traffic Flow
Figure 1-3 shows inbound connection flow for the Cisco AS5850.
Figure1-3 Inbound DS0 Traffic Flow
A typical user connection flows as follows:
1. The user PC connects to an attached or internal modem.
2. The modem call connects to a central office (circuit switched) and is multiplexed into a T1/E1, T3,
or STM1 trunk.
3. The T1, E1,T3, or STM1 interface is terminated, and individual serial DS0s are sent to port-handling
hardware and software. Universal ports may be located in the same physical slot, as part of a hybrid
trunk card, or in a universal port card (UPC). (See Figure1-3.)
4. Universal ports interface with modem protocols and convert TDM data into Ethernet packets.
5. Ethernet packets are routed and send out through the Fast Ethernet or gigabit Ethernet egress
interfaces to a backbone network.
T1/E1
CAT5
T3
COAX
OC3/STM-1
SMF
Modem
Twisted pair
Backbone
Network 1
(Gigabit Ethernet)
Backbone
Network 0
(Gigabit Ethernet)
Cisco AS5850
universal gateway
Backplane
2
1
T1/E1 trunk card
T3 universal port card
OC3/STM-1 trunk card
universal port card
GigE egress RSC
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