When a gateway transfers messages from the FirstClass BBS to the CommuniGate Server, it converts addresses in a BBS message into the standard Internet form.
Advanced users only: the following is the formal description of the address conversion algorithm:
If the CommuniGate domain name is cgate.com, and the gateway serves the FirstClass BBS with the site name BBS1, and there is also some other BBS with the sitename BBS2 that connects to the CommuniGate Server via the BBS1 site, then inactive (From) addresses will be converted as illustrated below:
FirstClass BBS address as seen on BBS1 |
Converted to: |
|---|---|
| Administrator | Administrator%BBS1@cgate.com |
| administrator,BBS1 | administrator%BBS1@cgate.com |
| James Bond | James_Bond%BBS1@cgate.com |
| administrator,BBS2 | administrator%BBS2%BBS1@cgate.com |
When Internet users answer to the Converted addresses listed above, their messages are sent to the CommuniGate Server cgate.com. The CommuniGate Router strips off the Server own domain name cgate.com, and the resulting address is parsed again, into the BBS1 domain name and a local part: a name of BBS1 user or a name and sitename for users of other sites.
Addresses in the form username%sitename@domainname are not convenient. There are two methods to improve address converting: using Internet domains as BBS site names and using Reverse Routing.
If the FirstClass site names contain dots, the CommuniGate domain name is not added to the end of the address, and the site name of the FirstClass BBS directly connected to the Gateway is not added to addresses of users on other sites. If you change the site names to BBS1.com and BBS2.com, then:
BBS address as seen on BBS1.com |
Converted to: |
|---|---|
| Administrator | Administrator@BBS1.com |
| administrator,BBS1.com | administrator@BBS1.com |
| James Bond | James_Bond@BBS1.com |
| administrator,BBS2.com | administrator@BBS2.com |
The site names (BBS1.com and BBS2.com) should be registered as domain with the Internet Domain Name System (DNS). The so-called MX records for these domains should be created. These records should route all mail for these domains to the CommuniGate Server. The domains for BBS systems must be different from the CommuniGate Server own domain name. For example, subdomains can be used: if the CommuniGate Server domain is cgate.com, BBS systems can get domain names (site names) bbs1.cgate.com and bbs2.cgate.com.
This solution cannot be implemented, if:
The CommuniGate Router is used to convert active addresses (i.e. recipient addresses). The FC-gateway uses Reverse Routing to convert inactive addresses (i.e. sender addresses).
<jbond> = James_Bond@BBS1 <jsmith> = John_Smith@BBS1 <mvery> = Mike_VeryLongName%BBS2@BBS1
When these records are created, messages sent to jbond@cgate.com, jsmith@cgate.com will be delivered to the BBS1 users James Bond and John Smith, and message sent to the mvery@cgate.com address will be routed to the user Mike VeryLongName on the BBS2 system.
When these users send messages via the FC-gateway, the gateway uses Reverse Routing: after converting the James Bond or the James Bond,BBS1 address into James_Bond@BBS1 the FC-gateway consults the Router table and converts that address back into jbond. Then it adds the CommuniGate own domain, cgate.com and sends the message with the From: jbond@cgate.com header instead of the ugly From: James_Bond%BBS1@cgate.com header.
This method allows you to "map" names of BBS users onto the "address space" of the CommuniGate Server: a username@cgate.com address can be assigned to each BBS user, and the username part in that address can be different from the name used inside the BBS system (James Bond -> jbond@cgate.com).
Note: you do not have to register all these usernames as the CommuniGate Server users, specifying aliases with the CommuniGate Router is enough.
If you register a new user with one of your BBS sites, but do not create an alias for that user with the CommuniGate Router, the new user will be able to send and receive Internet messages without any problem, but his/her E-mail address will look like username%BBS1@cgate.com
If you have many BBS users and you do not want to mix your CommuniGate user names with names assigned to the BBS users, you may want to register an additional domain for BBS user addresses. Usually providers do not charge extra for subdomains, so you should ask your ISP to create an MX record for a subdomain (such as bbsA.cgate.com) and to make that MX record point to your CommuniGate Server. Then enter the following line in the CommuniGate Router setting:
<*@bbsA.cgate.com> = *@BBS1
Now all your BBS1 users will get addresses in the bbsA.cgate.com domain (James_Bond@bbsA.cgate.com, etc.)
Instead of registering a subdomain, you may want to use a suffix and/or prefix to FirstClass users names in order to convert them into Internet addresses:
<*-fc> = *@BBS1
now all your BBS1 users will get Internet addresses in the form: James_Bond-fc@cgate.com.
Please note that you still can create individual alias records for BBS users, just place those records above the wildcard alias records:
<jbond@bbsA.cgate.com> = James_Bond@BBS1 <*@bbsA.cgate.com> = *@BBS1
If your FC-gateway is used to serve multiple FirstClass systems, include the Routing records for the directly connected BBS after all records created for other BBS sites:
<*@bbsB.cgate.com> = *%BBS2@BBS1 <*@bbsA.cgate.com> = *@BBS1
The Router table is scanned from top to bottom., and this line order allows the CommuniGate System to process BBS2 addresses correcly: user%BBS2@BBS1 is converted into user@bbsB.cgate.com, not into user%BBS2@bbsA.cgate.com.