| Internet addressing is the standard addressing format used to route and resolve Internet mail to appropriate mail hosts and user mailboxes. The format of an Internet address is username@Internet DNS domain name. Any email message routed across the Internet must adhere to this format. Following is an explanation of the portions of an Internet email address: Internet username: The username (or user ID) portion is an identifier for a mailbox in a mail system. For example, edekorte is the username for Erno de Korte. The username portion of an Internet address is typically controlled at the company or Internet service provider (ISP) level. Usually, companies or organizations specify a standard method for creating usernames, often using portions of users' full names. In this book's sample company, WorldWide Widgets, the naming standard for creating usernames is to use the first letter of the first name and follow it with the last name, without spaces. Internet domain name: The domain name portion of an Internet address is the string on the right side of the address following the @ sign. This string identifies the mail host that Internet users must reach when sending to a particular organization. For example, the username edekorte belongs to the domain name wwwidgets.com, so Erno de Korte's fully qualified Internet address is edekorte@wwwidgets.com. Usually, domain names are based on the actual company or organization name. In the example of this book, WorldWide Widgets is the company name, and the domain name that refers to WorldWide Widgets on the Internet is wwwidgets.com. When selecting a domain name, an organization has to pick a unique name and register that name so that no other organization will use it. Domain name registration: All registered domain names can be resolved through a domain name server (DNS). Domain names are registered through an organization called Internic. A DNS resolves domain names to show the actual Internet protocol (IP) address of the mail hosts that an organization uses to send and receive Internet mail. The DNS takes a domain name, which is like a zip code in the postal system, and translates it into an IP address of a mail host, which is like a local post office that handles mail for that domain. Tip Information regarding Internic, as well as information about how to register a domain name, can be found at www.internic.org.
Guaranteed uniqueness: The great value of having a central body such as the Internic in charge of domain names is that all domain names are guaranteed to be unique. Because the domain names are guaranteed to be unique, fully qualified Internet addresses are also guaranteed to be unique. For example, two users who have a common username will still be uniquely identified on the Internet, as long as the domain portion of the Internet address makes the entire Internet addresses unique. There are countless postmaster mailboxes on the Internet, but they are uniquely defined by the fact that their domain names are different.
All valid Internet email addresses will have the elements explained, no matter which email system is being used. Understanding Old-Style GroupWise Addressing Format Tip This section will help you to better understand the way GroupWise used to handle Internet addressing, and this knowledge might be very useful for your understanding of the system and your troubleshooting. However, if you just want to quickly set up "modern day" Internet addressing, you can skip this section for now and move on to the section "Benefits of GroupWise Internet Addressing."
A basic characteristic of Internet addresses is that the address is ordered from general to specific as the address is resolved from right to left. The most specific part of the address is the username, on the far left. The most general part is the upper-level domain name (for example, .com or .net) on the far right. Processes that read and resolve Internet addresses read backward compared to the way you are reading the text of this book. They start on the right side and work their way to the left. In contrast, old-style GroupWise addresses (prior to GroupWise 5.5 with Internet addressing) are resolved from left to right. They are still resolved from general to specific, though. This GroupWise address format is Domain.PostOffice.User (DPU). Note that a GroupWise domain is not the same as an Internet domain. GroupWise domains are created and named by GroupWise administrators, and they do not need to be unique worldwide. There is no central naming authority for GroupWise domains. The fact that GroupWise domains are not unique didn't matter until companies that had common domain names began to connect to each other. To make the mail between their systems routable, each company would have to alter the name of the external domain definitions they created so that their address books would not show two CORP domains, for example. As Internet connectivity became more and more common (almost as common as television!), GroupWise users realized that they had to know two addressing formats, one for users on their GroupWise systems and a different one for users elsewhere on the Internet. True Internet addresses, in which every name is guaranteed to be unique, leave no question as to what domain a piece of mail should be routed to, regardless of where the piece of mail originated. To communicate through the Internet, GroupWise had to conform to the standards of Internet addressing to allow GroupWise mail hosts to communicate with other Internet mail hosts. Old-Style GroupWise Internet Address Resolution "Old-style" refers to any GroupWise system that does not have GroupWise Internet addressing enabled. This means all versions of GroupWise before GroupWise 5.5 (on which the option was not available), as well as any GroupWise 5.5x to GroupWise 7 system on which Internet addressing is not yet turned on. As discussed in Chapter 10, "Installing and Configuring the GroupWise Internet Agent," GroupWise systems connect with the Internet through the GroupWise Internet agent (GWIA). This gateway allows GroupWise users to send email to Internet users by acting as a mail host and as an address resolver. The GWIA converts GroupWise addressing formats to Internet addressing formats, and resolves Internet addresses to GroupWise addresses. The gateway also acts as a mail host to physically send and receive mail from the Internet. The GWIA stamps the outgoing mail with an Internet-style return address. Incoming mail is converted to a GroupWise address format. For example, a message sent from Corp.CorpPO.edekorte to an Internet recipient will have its reply-to address changed to edekorte@wwwidgets.com. An incoming mail message from the Internet will have its delivery address converted from edekorte@wwwidgets.com to a GroupWise address of Corp.CorpPO.edekorte. Old-Style GWIA Creation of Reply-To Addresses When mail is passing from the GroupWise system to the Internet, the GWIA has to create an Internet-standard reply-to address from the GroupWise information so that Internet recipients of GroupWise mail can reply. The gateway formulates the reply-to Internet address by using the rules shown in Figure 16.1. Figure 16.1. The old-style GroupWise process for stamping reply-to on outbound messages, without Internet addressing enabled 
Here is a look at each of these reply-to addresses in turn, with each numeral in the following list corresponding to the number in Figure 16.1. We start at the upper-left corner of the diagram: 1. | If there is a fully qualified user Gateway alias for the GWIA (that is, the user alias has both a user portion and a domain portion), the reply-to address will be set to the user's alias. If Bob Snow's user Gateway alias is set to bobsnow@bob.wwwidgets.com, that will be his reply-to address.
Note If a user has more than one alias for the GWIA, the first listed alias will always be used for constructing the reply-to address. Tip As a general rule, we do not recommend using Gateway aliases anymore, for reasons we will explain later in this chapter. The biggest issue is that these aliases will be "stamped" on the email going through this particular gateway, but the associated email address is not visible in the rest of your GroupWise system, in your eDirectory or in the address books. | 2. | If there are a user alias and a post office alias, the reply-to address will be set to User Alias@Post Office Alias. For example, if BSnow's user alias is bobsnow, and the post office alias for his post office is sales.worldwidewidgets.com, the email he sends will be stamped with bobsnow@sales.worldwidewidgets.com in the reply-to field.
| 3. | If there is a user alias but no post office alias, the reply-to address will be set to User Alias@Foreign ID of GWIA. If the GWIA has more than one gateway foreign ID set, the first one on the list will be used.
Tip The GWIA's gateway foreign ID is defined under the properties of the GWIA. Figure 16.2 shows the Foreign ID field on the WorldWide Widgets GWIA. A GWIA can have multiple foreign IDs. The first foreign ID is the default foreign ID for the GWIA. Foreign IDs are separated (delimited) with a single space. The Foreign ID field on the GWIA cannot exceed 124 characters. If you have several foreign IDs, create an ASCII file in the DOMAIN\WPGATE\GWIA directory called FRGNAMES.CFG. List the main domain name, such as worldwidewidgets.com, on the first line. List each of the other domain names, such as sales.worldwidewidgets.com, on a line by itself. Put a blank line at the end of the file. Restart your GWIA so that it reads this file. Figure 16.2. The Foreign ID field for the GWIA must be filled in 
| 4. | If there is no user alias, but there is a post office alias, the reply-to field will be set to GroupWise UserID@Post Office Alias.
| 5. | If there is no user alias, and there is no post office alias, the reply-to address will simply be GroupWise UserID@Foreign ID of GWIA. This is the default case. A GWIA must have a foreign ID specified, and users must have a user ID; but aliases are not required.
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Old-Style GWIA Resolution of Inbound Internet Addresses Figure 16.3 shows what happens when a message is coming inbound to the GWIA. Figure 16.3. Old-style GWIA inbound message resolution 
Inbound Internet mail arrives at the GWIA when a foreign mail host connects to the GWIA and sends something in on port 25. Typically, this happens because the foreign host found an MX record (DNS mail exchange) matching the GWIA up to the domain portion of an address. If DNS says that worldwidewidgets.com resolves to the IP address of the GWIA, any message to any user at worldwidewidgets.com will get sent to that GWIA. This means that your GWIA could receive mail that is not destined for your GroupWise system. The GWIA needs to be able to deal with this situation. The rest of this section describes how mail coming through a GWIA is resolved to a GroupWise user address. We start again at the upper-left corner of the diagram. First, the gateway compares the domain name of the message recipient with all the foreign IDs of the gateway. This is where the GWIA is checking to see whether the mail is actually destined for your system. If there is a match, begin with step 1; otherwise, begin with step 4: 1. | If a match is found, the GWIA checks to see whether the user portion of the recipient address matches a user alias. If so, the message is delivered to that user.
| 2. | If there is no user alias, the GWIA checks for matches with user IDs and nicknames. If a match is found, the message is delivered to that user.
| 3. | If no match is found for user aliases, nor for user IDs and nicknames, the message is undeliverable.
| 4. | If the foreign ID string of the gateway does not match the domain portion of the address, the GWIA determines whether there is a match with a fully qualified user alias (a user alias in which both the user and domain portions of the address are specified). If the GWIA finds a match, the message is delivered to that user.
Tip We have seen situations in which step 4 of this algorithm did not work. It is just best to define all Internet domain names in the Foreign ID field or the FRGNAMES.CFG file. | 5. | If there is no fully qualified user alias, but there is a match between a post office alias and the Internet domain portion of the address, the GWIA will not receive the message. By default, the GWIA does not allow relaying, and the Daemon portion of the GWIA will not be able to fully resolve the address; hence, it will drop the message.
| 6. | If there are no alias matches, and the foreign ID did not match, the message is not really destined for this GroupWise system. If message routing, or relaying, is enabled, the GWIA will attempt to pass the message on to the correct SMTP host.
| 7. | If message relaying is not enabled, the message is undeliverable.
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Pitfalls with Old-Style GroupWise Addressing Before discussing native GroupWise Internet addressing, this section explores the limitations of the old-style addressing. Following are the pitfalls of the old-style GroupWise address: User training issues: With the prevalence of consumer Internet email, most users know how to address a message Internet-style. These users will want to be able to send to the Internet from GroupWise the same way they do from other email applications. Without GroupWise Internet addressing, these users must enter additional information to get their Internet messages out of the GroupWise system. Specifically, they must enter the domain and gateway name of the GWIA before the address, or they must enter the name of a foreign domain that has been associated with the GWIA. Thus, outbound messages are typically addressed internet:user@domain. A message simply addressed to user@domain will not make it out of the GroupWise system. GroupWise addressing rules can be used in place of true Internet addressing. This will alleviate the user training issues, but it won't help in other areas. GWIA limitations: Another potential problem with this traditional handling of address conversion is that the gateway might only narrowly interpret incoming mail as being part of its GroupWise system. This limitation is primarily due to the way in which the GWIA looks at its Foreign ID field/FRGNAMES.CFG file. Addresses that don't match this field (or don't match user or post office aliases) might be marked undeliverable. User alias limitations: A third problem lies in limitations of GroupWise user aliases. Only two addresses per gateway can be used to identify a GroupWise user. For example, Erno de Korte has a mailbox ID of edekorte and a user alias of erno.dekorte@worldwidewidgets.com. This means that his outgoing Internet mail will be sent to the Internet as being from erno.dekorte@worldwidewidgets.com, and he can receive email bound for the address of either edekorte@worldwidewidgets.com or erno.dekorte@worldwidewidgets.com.
Hopefully by now we've convinced you that you need to enable Internet addressing, which is discussed in the next section. Benefits of GroupWise Internet Addressing GroupWise Internet addressing offers several advantages over the old-style GroupWise addressing format. Following are some of the advantages of Internet addressing: GroupWise addresses become true Internet addresses. GWIA gains flexibility as it resolves Internet addresses to GroupWise users. Client addressing rules might no longer be needed. GroupWise systems can connect to each other natively, without defining external domains. Certain features of GroupWise require Internet addressing.
Here is a discussion of each of these in turn: GroupWise addresses become Internet addresses: With native Internet addressing, GroupWise addresses no longer need to be converted to Internet addressing formats when GroupWise mail is being sent out to the Internet. Instead of users being known internally to the GroupWise system as Domain.PostOffice.User, users will be internally known as UserID@Internet domain name. GWIA gains flexibility: With Internet addressing enabled, the GWIA will work very hard to match an Internet address with a GroupWise user for incoming SMTP mail. The gateway will still look for the old-style matches with aliases and foreign IDs, as well as the following Internet domain name formats: Full: User.PostOffice.Domain@Internet domain name Post office unique: User.PostOffice@Internet domain name User ID unique: User@Internet domain name First, last: FirstName.LastName@Internet domain name Last, first: LastName.FirstName@Internet domain name First initial, last name: Firstinitial.LastName@Internet domain name Free-form Internet address: Any RFC-compliant characters@Internet domain name
Tip The free-form Internet address format was new to GroupWise 6.5 and is of course still available in GroupWise 7. This is not enabled at the system level as the other formats are. It can be implemented as an override option at the user level. For the free-form Internet address override to work, the user's post office and domain, and your GWIA, must be at GroupWise 6.5 or 7. If any of these agents is not at version 6.5 or 7, the free-form address might not work properly. Also, if the post office is not at version 6.5 or 7, the ConsoleOne snap-ins do not even display the free-form field for you to use.
The term Internet domain name is specific to GroupWise Internet addressing. The Internet domain name is an extra attribute attached to every address in GroupWise, and therefore makes GroupWise addresses comply with Internet address formats. Note Internet domain names are sometimes referred to as IDOMAINs. This term might help avoid confusion.
Client addressing rules are no longer needed: When Internet addressing is enabled, client addressing rules are no longer needed to route mail messages to the Internet. Because GroupWise addresses are Internet addresses, mail addressed Internet-style will be correctly routed to the GWIA without the explicit address of the GWIA. Also, turning on Internet addressing will enable GroupWise users to send to other internal GroupWise users or external Internet users by simply typing the Internet address, such as UserID@Internet domain name. Internet addressing removes the need for addressing rules that search for an Internet-style address and replaces the address with a GroupWise gateway:internet address or with an external foreign domain:internet address. Direct MTA-to-MTA connectivity between systems: With Internet addressing enabled, you can allow any message transfer agent (MTA) on your system to connect directly to another GroupWise system. The GroupWise message transfer protocol (GWMTP) allows GroupWise users to transparently communicate over the Internet with other GroupWise users in other systems. GWMTP sending effectively eliminates the need to convert messages bound to other GroupWise systems. No gateway or gateway conversions are needed for the two systems to communicate. Leaving the messages in their native format also allows for native GroupWise encryption, compression, and message formats to be retained. Keeping the native message type allows appointments to be sent to users in other GroupWise systems as appointments. These items will show up correctly on calendars, and can be accepted or rejected, and full status tracking is available. The native format also allows for busy searches across the Internet GroupWise systems. You can find more about this in Chapter 34, "Creating a GroupWise-to-GroupWise Communication Solution Across the Internet." Future GroupWise enhancements will require Internet addressing: Several GroupWise features require Internet addressing to be turned on. One current GroupWise feature that requires Internet addressing is Junk Mail Handling. Third-party solutions will require Internet addressing: User and Post Office Gateway Aliases are stamped at the gateway level and are not shown in eDirectory, the GroupWise Directory Store (Domain and Post Office databases), which is the basis for the GroupWise System address book. Imagine the problems for a third-party developer if he cannot simply rely on the fact that the Internet email address of a user is properly stored in eDirectory or in the GroupWise Directory Store.
Although when you install GroupWise it does not require you to enable Internet addressing, you should enable it as soon as possible. Potential Pitfalls in Enabling Internet Addressing Tip If you have created a new GroupWise system or have used Internet addressing before, the next section might be of interest only as a means for you to fully understand all the issues. If you're not really interested, you can skip this section and move on to the section "Enabling Internet Addressing."
GroupWise functionality is becoming entrenched in Internet addressing. It is likely that you will eventually have to enable it for full functionality. Unfortunately, enabling Internet addressing is not without a few potential hazards, including these: Personal address books are converted to Internet address formats. Legacy clients like the GroupWise 5.2 Mac client, which is sometimes still used, need to use this old addressing format. Client Internet addressing rules are no longer used. Turning off Internet addressing isn't really an option.
The following discussion goes over each of these issues in turn: Address-book conversion to Internet address formats: When Internet addressing is enabled, users' address books will be converted to Internet addressing format for the email address column. This means that gateway names will be removed, as will foreign domain names. In some circumstances, we have seen the conversion process fail for some addresses. You might want to be alert to delivery problems for the first few weeks after Internet addressing has been enabled. Legacy clients still use the old addressing format: You might have GroupWise 5.2.7 Macintosh clients on your 6.x post offices. These clients need to use the old addressing scheme. For these legacy clients, you will need to maintain your foreign domain names (for Internet-style addressing), as well as your addressing rules. GroupWise 5.5x and GroupWise 6x clients ignore some addressing rules: When Internet addressing is enabled, all GroupWise 5.5x and GroupWise 6x 32-bit clients will no longer use certain addressing rules. If a rule executes on address strings that contain an @ sign followed by a dot (.) and replaces it with a string that includes a colon (:), that rule will be ignored. For example, an addressing rule that searches for *@*.com and replaces that string with inet:%1@%2.com will be ignored by the 5.5x and 6x clients when Internet addressing is enabled. This should not be a problem, but it is possible on large systems that addressing rules meeting these criteria will still be needed for some reason or another. Turning off Internet addressing can be painful: The biggest disadvantage to enabling Internet addressing is that you cannot really back out of it.
If you do have problems enabling Internet addressing, seek technical support help rather than attempting to turn it off. |
