Return to the Internet Fundamentals PageOne of the major motivations for connecting computers together in a network is improved communication. Anyone who has ever suffered the frustration of "playing telephone tag" knows that an audio recording device such as a telephone answering machine can help to combat incompatible schedules. But voice messages are often not sufficiently detailed to communicate the needed data, nor do they provide a written copy of the message. Since networks allow us to transmit and store documents, e-mail was a natural development. By simply giving each user an identifying userid or username and a dedicated storage area called a mail box on a network Mail Server, we then have a way to address and store mail for a specific user. This approach allows you to record a message when convenient and then send it off to be stored on the machine where its intended recipient's mail box is located. The message can then be read at the recipient's leisure by using a Mail Client to connect to the mail server on which his or her mail box is maintained to access the waiting mail. Many mail servers can even send notices back to the sender to indicate when the message arrived in a recipient's mail box or when it was read. Often, a request for a receipt is honored only by a mail server on the same network. Other requests are ignored.
Originally, the contents of e-mail messages was restricted to just text, but many systems can now transmit other forms of data such as graphics, programs, and digitally recorded audio. The simpler text-base system used a protocol called SMTP or Simple Message Transfer Protocol. The newer, more sophisticated protocol is called Post Office Protocol or POP. (Note: POP is also an acronym for "Point of Presence", indicating a location that can be dialed into to connect to the Internet).
The implementation of e-mail on the Internet is based on an approach to messaging called store & forward using the TCP/IP network protocol along with SMTP and POP. Messages are relayed from host to host in much the same way that conventional mail (called snail mail by many e-mail users) is passed from one post office to another while en route to its destination. Internet e-mail software divides mail into packets and finds the fastest route for transmitting them to their target address. It will even hold mail for intended recipients if their host computer is temporarily inaccessible. This is necessary because not all hosts maintain a permanent connection to the Internet.
Many e-mail software packages exist. You may have more than one to choose from on your network. They offer a variety of messaging services, including:
generation, editing and storage of text messages
transmission of messages to other mail boxes or hosts
automatic addressing of responses to received messages
indexing and directory listing services for your mail box
inclusion of courtesy copies of messages to users other than the original recipient
attachment of other files (of any data type) to transmitted messages
the ability to forward received messages to a different recipient
generation of an automatic reply to all incoming messages when desired
encryption services for improved security
maintenance of distribution lists that list groups of recipients under a single identifier
maintenance of personal address books that allow users to use nicknames instead of long addresses
Read the manuals and the help screens provided by your e-mail system to learn more about the services it offers.
Folders, Message Headers, TO: CC: Subject:, Body, Signature, Attachments
Most Internet hosts offer e-mail service. This is true of public services such as America Online (AOL), CompuServe, Delphi, Prodigy, and local ISP's. Each of these services has its own local e-mail system. Messages sent to mail boxes on the same host will need to be addressed only with the intended recipient's userid. However, messages intended for transmission outside of the domain of that host will require you to provide a more detailed address, including enough information for the software on your network to find the target host. Many local systems require their users to perform some extra step or acquire some additional software to send e-mail outside of their system to the Internet. Check with your service provider for details.
IRCC employees and students can arrange e-mail accounts on IRCCNet. These accounts can be manipulated using any standard Mail Client (program). Students in IRCC classrooms can use the Mail Client in Netscapeâ to access a restricted Student Mail Server. This software provides all of the services outlined above. Any Internet Mail Client can be used on home computers to access IRCCNet e-mail accounts. IRCCNet can be accessed through a local dial-up phone numbers in Saint Lucie, Indian River, Martin, and Okeechobee. IRCCNet account holders can connect to IRCCNet from any peer anywhere on the Internet. Those who have purchased access accounts will be given instructions on how to dial into IRCC from home to submit or receive assignments via e-mail and use other resources available through our site.
The Anatomy of an E-mail Message:
A typical e-mail message consists of at least two parts, its header and its body. The header contains the addressing information and any special characteristics or instruction assigned to the message. The body contains the text of the message. The content of an e-mail header will differ depending on the client used to create the message, but most headers will contain at least the following fields of data:
The date of the message and the return e-mail address of the sender (automatically added)
E-mail address(es) of the intended recipient(s), usually identified by the field label "To:"
E-mail address(es) of people who should receive courtesy copies, usually identified by the label "CC:"
A title for the message, usually identified by the label "Subject:"
To send e-mail outside of your own network to an Internet user with a username of "WJohnson" on a host with the machine name "thinker.fsu.edu", you would address the message to:
WJohnson@thinker.fsu.edu
An Internet user outside of IRCC would address mail to someone with an IRCC account by using his or her username, followed by an @ symbol, followed by the host name of the computer that receives e-mail on the IRCC.NET network. The IRCCNet Mail Server is named mail.ircc.net. Thus, my Internet e-mail address on IRCCNet is:
RGibson@mail.ircc.net -or more simply - RGibson@ircc.net
The machine name of "mail" can be omitted because IRCC only has one mail server on the IRCC.NET network. Note that e-mail addresses are not case sensitive. The user name “rgibson” works just as well as “RGibson”. Another IRCCNet account user could address a message to me by simply using my userid of "RGibson" (without the @ symbol or host name) because we both use the same host.
Most e-mail software allows its users to store and maintain their own electronic address books of frequently used addresses. Each address can be given a brief alias that you can easily remember and type whenever you want to use an address in your book. For example, rather than searching for William Johnson's address every time I want to send him a message, I can record an entry for him in my personal address book similar to:
Will WJohnson@thinker.fsu.edu
In the future, whenever I am addressing a message to that person, I could then simply use the label "Will" and my Mail Client will then recognize it and substitute his full Internet address for me. Most address books can also store a distribution list which is a list of email addresses that can be addressed using a single label.
Signatures:
Most e-mail messages conclude with fairly standard block of text that includes the sender's name, return e-mail address, "snail mail" address, phone number, and other personal information. For this reason, most Mail Clients allow users to store a standard signature (identifying block of text) that the software will append to the end of all future messages. This signature can be edited or overridden at any time.
Most e-mail messages consist of simple "text", in other words, only the characters that you find on a computer keyboard. Text is represented in most computers using a language named ACSII (the American Standard Code for Information Interchange). ASCII only allows for 128 standard symbols and does not include any provision for text enhancement such as boldface, underline, italics, or different typefaces or sizes. Occasionally, you may want to send enhanced text or other forms of data such as a drawing, a picture, audio or video data, or a computer program. If so, you will have to send this non-text data as an attachment. An attachment is additional data that is included with your e-mail message and goes along for the ride to the same address. The manner by which attachments are handled by e-mail programs differs with each program. Most offer a field (data item) within the header of the message for indicating the filename of the object to be attached and then have a command or menu choice that a recipient can use to detach the file for independent use.
Beware that many old e-mail programs do not handle attachments well. Some try to translate attached data into code that resembles text in an attempt to pass the attached data through old networks that do not support the transmission of non-text data. This action is called encoding. The recipient's e-mail system will need the ability to decode the attachment before it can be read. If the e-mail software cannot decode the attachment, you will need to save the message with the attachment and acquire a decoding program for use on it later.
Attachments that are transmitted successfully may still represent a challenge to the recipient. Remember that the recipient will need to have the same program (& version of it) that you used when you saved the attached file in order to load and interpret it. Some programs can read data that was created by a different program, but this is the exception rather than the rule.
One username that exists at almost all e-mail sites is "postmaster". This is a special username used by the personnel who maintain each host's e-mail system. Any questions that you have about an e-mail system that you cannot resolve by reading network documentation should be addressed to that system's postmaster. Do not bother these people with simple or routine questions that could be answered by simply reading the Help Screens or FAQ's, as they will simply refer you to those resources if you do ask for this type of help. And definitely DO NOT ask them for people's e-mail addresses! Directory service is not their job!
Security for e-mail is provided partially by assigning each account a password that must be entered at the keyboard before it can be used. Most users are allowed (in some cases required) to change their personal passwords periodically just in case someone else has discovered the original. Most systems also provide encryption services for encoding and decoding messages to prevent unauthorized interception. But beware that e-mail is not 100% secure. Sufficiently clever and unscrupulous people could read your mail or even alter it. Occurrences of this are quite rare, but can happen.
Before you can send a message, you must have the e-mail address of its recipient. The most obvious way to get the address is to ask the recipient. If this is neither possible nor practical, you will have to search for the address in either manual or electronic directories. Many systems maintain directories of their users for public review and some Internet sites have collected large databases of these. However, many hosts do not maintain publicly accessible directories. So finding e-mail addresses is not always an easy task.
The most popular programs written to help network users to search existing user databases are Finger, Whois, and Netfind. Many WWW sites now exist that serve as voluntary e-mail registries. Some popular web based e-mail registries are LookUP! and Yahoo! People Search (formerly Four11). As e-mail becomes more widely used, you will notice more directories appearing and will even notice that people are starting to put their e-mail addresses on their business cards and personal correspondence.
These are services that maintain directories of information on individuals, often listing a person's name, organization, and email address. You can find the latest resources listed at sites such as the Library of Congress, Netscape, Yahoo, etc.
Return to the Internet Fundamentals Page| Last Revised: 3 November 2003 | © 2003 Randolph U. Gibson |
| www.gibson.vero-beach.fl.us/classes/internet/email.html | E-mail: rgibson@ircc.edu |