Specifications

SX-200 ICP General Information Guide
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• Call Offer: Camp on
• Networked Voice mail
• Networked Attendant
• Message Waiting Indicators
• Network Voice mail Softkeys
Ethernet WAN and LAN interfaces
In addition to standard telephony interfaces, the SX-200 ICP CXi includes a complete range of
Ethernet interfaces. It has a WAN interface for connection to the Internet at 10 or 100 Megabits
per second. The WAN interface can obtain an IP address by DHCP or PPPoE, or be
programmed with a static IP address and default gateway.
The 200 ICP CXi also has a 16-port, 10/100 Layer 2 switch for connection to an Ethernet LAN.
Each of the 16 ports provides power to IP devices in compliance with the ’Power over Ethernet’
specifications in IEEE 802.3af.
The 200 ICP AX has a two-port, 10/100 Layer 2 switch for connection to an Ethernet LAN.
The CXi also has an unpowered 1 Gigabit Ethernet port for connection to another switch on
the LAN. By connecting another switch, it is possible to increase the connection capacity for
the CXi from 16 to 100, with 16 connected to the onboard switch and 84 connected to the
offboard switch(es).
The internal switch uses a traffic prioritization scheme based on IEEE 802.1 p/Q VLAN
prioritization standards. This ensures the quality of voice calls by routing packets with priority
value 6 (from IP phones) ahead of packets with priority value 0 (from PCs and other IP devices).
Internet Gateway (CXi only)
The primary function of the Internet Gateway is to link the internal and external networks. In
this role, it performs many-to-one NAT (Network Address Translation), converting private IP
addresses on the LAN to a single public IP address on the WAN interface. NAT redirect, or "IP
port forwarding," is included as a programmable feature, enabling external traffic to reach
internal services or machines. The Internet Gateway also provides firewall functionality, logging
unknown packets and then either dropping or rejecting them, or allowing the packets to pass
through to the internal network. If VPN tunnels are in use, the Internet Gateway can perform
IPSec and PPTP pass-through, and can function as a PPTP server.
Embedded firewall (CXi only)
The firewall examines all packets destined for the internal network. Unless they are addressed
to a specific TCP or UDP port programmed on the firewall, the packets are declared "unknown"
and then either dropped or rejected. Unknown packets are also logged.
Note: IP Trunking is not supported over the CXi WAN interface. All IP Trunks must be
via the LAN interfaces (AX, CXi and MX).