Chapter 1: Understanding ISDN and the Express XL/XLT
Network Address Translation Mode
NAT is a special mode of operation in which the Express XL/XLT obtains a dynamically assigned IP address from the peer router (typically an Internet Service Provider). This allows a network of computers to benefit from Ether- net to ISDN speeds while still appearing to the Internet Service Provider (or central site router) as a single IP address which is typical of PC based serial
A call is initiated to the ISP using the Dial menu or demand for a Connection List profile that has the IP parameter NAT set to Yes. The network computer’s IP stack may use DHCP to request an IP address, default gateway address, and domain name server addresses from the Express XL/XLT.
Front Panel
Figure 1-6 on page 17 shows the front panel of the Express XL/XLT. The indi- cators are divided into LAN functions, WAN functions, and Test functions.
LAN Indicators |
|
RX | Flashes when receiving data from the 10BaseT connector. |
TX | Flashes when transmitting data onto the 10BaseT connector. |
LI | Link integrity. Illuminates when there is a good connection |
| between the Express XL/XLT and the Hub/NIC card. |
COL | Illuminates when a collision occurs on the 10BaseT. |
JAB | Indicates a jabber condition on the 10BaseT. |
16 | Express XL/XLT User Manual |
