  Understanding Internet Services protocols
Although Internet Services is implemented as a single protocol module, it is actually comprised of multiple protocol services: gateway, client, and Directory.
Gateway services
Gateway services moves bulk content in and out of FirstClass using
• Simple Mail Transfer Protocol (SMTP)
• Network News Transfer Protocol (NNTP)
• Internet Mail Application Protocol (IMAP4)
• Post Office Protocol 3 (POP3) importer
• Hyper Text Transfer Protocol (HTTP) for web servers.
Client services
Client services renders FirstClass Network Store content to alternative clients using
• HTTP
• File Transfer Protocol (FTP)
• POP3 client
• IMAP4 client.
Directory services
Directory services renders Directory content to alternate clients using
• Finger
• Lightweight Directory Access Protocol (LDAP).
File services
File services lets you access FirstClass and non-FirstClass documents with Internet Services acting as a file server using
• File Transfer Protocol (FTP)
• Common Internet File System/Server Message Block (CIFS/SMB).
Protocol definitions
The definitions described in this section are general in scope and follow basic industry standards.
Mail delivery
Mail delivery refers to sending and retrieving email between different accounts and is handled differently by different mail protocols (for example, SMTP, POP3, and IMAP4). The diagram below shows the path of delivery for mail sent from one account to another through the Internet:
SMTP
SMTP is a protocol for sending email messages between servers. Most email systems that send mail over the Internet use SMTP to send messages from one server to another; the messages can then be retrieved with an email client such as FirstClass. In addition, SMTP is used to send messages from a mail client to a mail server but not to retrieve messages from a mail server to a mail client. This is why you need to specify both the POP or IMAP server and the SMTP server when you configure your email application.
POP3
POP is a protocol used to retrieve email from a POP3 mail server. Most email applications use the POP protocol.
IMAP4
IMAP is a protocol used to retrieve email messages from an IMAP4 mail server. IMAP4 is similar to POP3 but supports some additional features. For example, with IMAP4, you can search through your email messages for keywords while the messages are still on the mail server. You can then choose which messages to download to your machine.
Web browsing protocols
Web browsing refers to searching for and accessing content on the World Wide Web (WWW).
HTTP
HTTP defines how messages are formatted and transmitted, and what actions web servers and browsers should take in response to various commands. For example, when you enter a URL in your browser, this actually sends an HTTP command to the web server directing it to fetch and transmit the requested web page.
HTTPS
HTTPS defines how data is transmitted securely over the web. Messages are transmitted and accessed in a secure environment using Secure Socket Layer (SSL). Web pages that require an SSL connection start with HTTPS, instead of HTTP.
File transfer protocols
File transfer refers to uploading and downloading server files.
FTP
FTP is a protocol used on the Internet for accessing files. Some organizations have a designated FTP server used only for uploading and downloading files for their users, see Using the File Transfer Protocol.
CIFS/SMB
CIFS, also known as SMB ( Server Message Block) is a Microsoft OS file sharing protocol. It allows you to mount your FirstClass Desktop as a network file system and access folders and uploaded files from a network directory (for example, Explorer). For information on configuring CIFS/SMB on your system, see Using the Common Internet file system.
Directory search protocols
Directory search refers to accessing user accounts in an information directory.
LDAP
LDAP is a directory access protocol used to search, read, and write directory information over a network. LDAP supports TCP/IP, which is necessary for any type of Internet access.
FirstClass LDAP support consists of Internet Services listening on the LDAP TCP port (389) and servicing lookup requests. Using any LDAP client, for example Outlook Express, you can access your FirstClass Directory including your network Address Book. FirstClass LDAP support includes both authenticated and unauthenticated access but does not support using LDAP to update the FirstClass Directory (no Dir Sync) or credentials lookup. If you access a name in FirstClass using LDAP these are the information fields you get:
• Name
• Email address
• Company
• Department
• Web page
You can set what your users can view in the Directory (accessed through LDAP or any other protocol) using FirstClass Directory filtering, see About the FirstClass Directory in the Administration online help. For example, you can configure your system to prevent unauthenticated users from accessing your system's Directory, while authenticated users can continue to have full access to the Directory including their network Address Book. To configure the LDAP protocol for your system, see Basic Internet Setup - Directory tab.
Finger
Finger is a UNIX program that takes an email address as input and returns information about the user who owns that email address. On some systems, finger only reports whether the user is currently logged on. Other systems return additional information, such as the user's full name, address, and telephone number, which the user must first enter.
Understanding domain names and IP addresses
You can think of domain names as the user-friendly form of an IP address. Users find it easier to remember addresses such as www.huskyplanes.com, as opposed to numbers, such as 192.166.0.0. A domain name identifies one or more IP addresses.
An IP address is a unique number that identifies a specific machine, for example, your mail server, web server, FTP server (if any), an end user computer.
If you are using Windows, you can define multiple IP addresses (that is, you can define multiple servers) on your network interface card (NIC). If you choose not to define multiple IP addresses, you should list your default domain IP address on the Multiple Sites & Languages form. You can also register multiple domain names and point them to one IP address, see Using the Multiple Sites & Languages form.
Domain names are used in both URLs and email addresses to identify particular web pages and email recipients respectively. For example, the Husky Planes web site address is www.huskyplanes.com. The domain name is huskyplanes.com and represents one IP address, 192.166.0.0. Roy Allen’s email address on Husky Planes is roy_allen@huskyplanes.com, where roy_allen signifies the recipient’s unique user name.
 NoteEach user on your system must have a unique email address. Otherwise, you may find your server unable to distinguish between two recipients and, thus, unable to properly deliver mail.
Every domain name has a suffix that indicates which top level domain (TLD) to which it belongs. There are only a limited number of such domains such as
• gov – Government agencies
• edu – Educational institutions
• org – Organizations (nonprofit).
|