Special Issues 483gateway. This occurs because the ConneXtions software makes H.323ports look like hardware line cards to a Call Processor.To emulate a group of simulated line cards, the gateway system mustread the destination address of every frame that is presented to itsNetwork Interface Card, instead of responding to only one hard-codedEthernet address. The gateway system is able to examine every Ethernetframe because its NIC does not discriminate between frames. The NICpasses every frame that it sees to the software for address evaluation.To reduce the load on an H.323 gateway, you can connect it to anexisting multi-port switch. For optimum performance, use switches thatsupport 802.1(p and q). The 802.1(p and q) standard offers priorityenhancement which NBX systems exploit. Most 3Com switches supportthis feature.Remote Access Business people who travel can make routine calls without long distanceline charges by using an internet-ready laptop with Microsoft NetMeetingto make H.323 calls, and a Virtual Private Network (VPN) connection tothe NBX system LAN. Microsoft NetMeeting software works withWindows 2000 and it can be downloaded for free fromwww.microsoft.com.You can use Microsoft’s VPN Dial Up Networking (version 1.3) to establisha virtual private network connection between a roaming laptop and theNBX system LAN. One end of the VPN connection is in the laptop whilethe other end must be located in a VPN server between the router andfirewall.The VPN server provides caller authentication and a secure (encrypted)channel across the internet. After a caller has been authenticated, theconnection is passed to the firewall, which sees the VPN connection ascoming from a recognizable (and therefore firewall-configurable)IP address. VPN allows a business person to establish an IP connectioninto the NBX LAN from a hotel room with internet service.After an Internet connection has been established, change yourautomatic call forwarding number:1 Log on to NetSet as a user.2 On the User Information tab, click Call Forward.3 Click the telephone number radio button.
