the Branch Office could access the Headquarters General Server via the Echo LANlink, but accesses to the Finance Server could be stopped using subnet masking in the Echo LANlink.
Figure 2 Restrictive Firewall Example
In addition to the features of the router, all the existing functions of the Echo LANlink are still available. This means that as well as connecting two remote LANs, the Echo LANlink can also carry PABX voice traffic (using D&I option card or ADPCM option card), and data traffic between the two sites, all simultaneously multiplexed onto one E1 communication link.
Echo LANlink Router Option User Manual | Issue 1.0 04 December 1997 Page 8 of 59 |