SkyFile FAQ

Using SkyFile Mail
Using SkyFile via Inmarsat-B/M/F
Mails and SMS messages to SkyFile users

SkyFile-C via Inmarsat-C
Using an Inmarsat-C transceiver for e-mails
Mails from the Internet to Inmarsat-C

Tools and more
Test of black&white list
Messages in bounce mails

This information is based on the land-earth station of Vizada (formerly France Telecom Mobile Satellite Communications) and the satellite gateway/client software from Shamrock Software.

Using SkyFile Mail

You will need a registration at Vizada.
Which Inmarsat services are supported by SkyFile?
What are the advantages of SkyFile compared to other software?
Why should I send faxes using SkyFile?
The external COM port of my laptop is not displayed
The mail transfer does not work
Is it useful to pack attachments into a ZIP file first?
What can I do against unwanted mails (spam)?
Is it possible to redirect my mailbox or to read it from the Internet?
To which countries and networks can I send SMS messages?
In which order do e-mails appear in the message list?
Is it possible to use SkyFile in a network with several PCs?

Which Inmarsat services are supported by SkyFile?

SkyFile supports all connection-oriented and packet-based Inmarsat services:

Inmarsat-B is the digital successor of the former Inmarsat-A. Besides its high-quality phone service, it also allows data and fax communications with reliable 9600 bps through the internal modem of the transceiver. The B-High-Speed service offers 64 kbps and is compatible with ISDN lines. A parabolic antenna is required.

Inmarsat-Phone (Mini-M) is a relatively new service including telephony, fax and data transfer (2400 bps) using small, portable sets with integrated flat antennas. It uses a digital speech encoding similar to terrestrial GSM radio telephone services.

Inmarsat-M4/Fleet offers ISDN capabilities with 64 kbit/s via satellite for high-quality speech and fast data transfer. M4 is the land-mobile version, Fleet for maritime use. The medium also offers Internet access via the Mobile Packet Data Service (MPDS) which uses a volume-based tariff with no time charges. The variants Fleet 33 (9600 bps in spot beams only, 2400 bps global), 55 (64 kbps in spot beams, 9600 bps global) and 77 (64 kbps global) primarily differ in the required antenna dish size and transmitter power.

BGAN (Broadband Global Access Network) has a volume-based tariff similar to MPDS and also runs over the Inmarsat satellites as a packet-based Internet access with 128 kbps and more. RBGAN (Regional BGAN) works with relatively compact transceivers via the Thuraya satellites, covering most parts of Europe, Africa and southwest Asia.

Alternatively, the low-orbit Iridium satellites are available even in the polar regions, offering speech and 2400 bps data. The service reliability does not meet the GMDSS requirements, however, so Iridium is not sufficient as a distress system.

^ Index

What are the advantages of SkyFile compared to other software?

Within a few months SkyFile became one of the most popular e-mail programs amongst Inmarsat users. Many ship owners, international organisations and military services are using SkyFile today. The reason is simply that SkyFile is specifically designed for the special requirements of satellite communications, so it works more reliable and cheaper than conventional e-mail programs. Each day many thousands of e-mails are transferred using SkyFile.

The following table shows the main differences of SkyFile in comparison to conventional e-mail software like Outlook. Most Outlook parameters are also true for other popular mail software like Netscape, Lotus, Eudora, or Pegasus.

The following form calculates the typical connection time for SkyFile in comparison to other e-mail programs like Outlook when receiving one file. If you change the file type or size, the result will follow your data automatically. The connection time includes modem negotiation and log-in duration.

For instance, Inmarsat Mini-M transmits 2400 bits per second. One byte contains 8 bits, so the theoretical maximum transfer speed is 300 bytes per second. SkyFile allows even higher rates if the data is compressible. - The difference in connection time between SkyFile and other mail programs are the result of several factors:

• The MIME-base64 coding of Outlook and similar programs requires 8 bits for each 6 bits of net data. SkyFile uses a transparent transfer, which gives 33 % more performance.
• SkyFile compresses typical text, Word, Excel and similar files online, typically saving 50 % of time.
• The SkyFile log-in procedure is very fast, requiring less steps than the typical POP3 log-in of other programs.
• SkyFile receives and sends data in parallel at the same time, saving up to 50 % of time.
• Due to the propagation delay, each dialogue step typically consumes more than one second over satellites. SkyFile reduces the number of steps for sending and receiving one e-mail from 23 (conventional POP3/SMTP over PPP) to only four, additionally saving more than 30 seconds:

^ Index

Why should I send faxes using SkyFile?

Using the fax printer driver in SkyFile, you may use any Windows application like MS Word, Excel, and many others to send text or graphics as a fax. The "trick" is that the fax is sent securely to the gateway using SkyFile's error-correction and compression capabilities.

Then the gateway at the land earth station will send the fax to its destination over the land line. This is much cheaper and more reliable than sending faxes directly from the Inmarsat transceiver. You will get a confirmation e-mail later which shows if the fax could be sent correctly. (The same thing happens if you send an SMS message.)

^ Index

The external COM port of my laptop is not displayed.

In some cases external serial ports like those in USB or PCMCIA adapters do not appear in the device list of most applications so that they cannot be selected.

If this happens, you should launch the Regedit program and search for this key:

HKEY_LOCAL_MACHINE\Hardware\DeviceMap\SerialComm

To activate a COM1 port, for instance, you have to create a new string with the name "COM1" and the value "Com1" in Windows 98. For Windows NT, 2000 or XP the string must have the name "\Device\Serial0" and the value "COM1". - Please note that changes to the registry should be done by experienced personnel only.

^ Index

The mail transfer does not work.

Please open the transfer log in the SkyFile menu. Typical problems include wrong username or wrong password (upper or lower case is not relevant here, but perhaps the letter O was used for the digit 0, or vice versa).

If you get a connect but no log-in happens, you may have used the wrong land-earth station. SkyFile can only be used over the Vizada LES. Other land earth stations may have a modem line behind the same short access code 28#, but there is no SkyFile gateway at the other end.

Please also check the following causes for the problem:

• Does the cable from the PC to the Inmarsat transceiver have all necessary connections? (Gnd, RxD, TxD, CTS, RTS, DTR, DSR, DCD are required, RI is optional.)
• Does the transceiver's or the modem's baud rate match the baud rate configured in SkyFile?
• Is the mail you want to send below the file size limit configured in SkyFile?
• Does the transceiver or modem use RTS/CTS handshake (hardware flow control)? XON/XOFF must not be used. Please see your transceiver's or modem's manual for how to configure hardware flow control..

^ Index

Is it useful to pack attachments into a ZIP file first?

SkyFile uses a very efficient online compression algorithm, which is quite similar to the one used in ZIP software. Typical text files are compressed to 50 % or less.

If you transfer many small attachments in one e-mail, you may save a few seconds of connection time by putting all attachments into one single ZIP file, so that you effectively have only one attachment. This will avoid the short handshake times between all the attachments.

For typical e-mails with no or only a few attachments, however, there is absolutely no advantage sending them as ZIP files.

^ Index

Is it possible to redirect my SkyFile mailbox or to retrieve it via ISDN?

You can redirect a free mail account like GMX, Bigfoot, Yahoo or others to your SkyFile address while you are using your Inmarsat transceiver. When you are back home later, simply deactivate this redirection at your free mail provider. However, we recommend not to use such a redirection because it makes filtering spam very unreliable.

Your SkyFile account cannot be redirected to a different e-mail address - the server and its backbone connection are not intended for this sort of usage, since it would increase the data volume of the mail gateway significantly. This non-Inmarsat traffic could also slow down the server response and therefore increase the cost of exchanging mails via satellite, which of course is not intended.

You can use the web interface of the SkyFile server to read, answer and forward received e-mails with any web browser. The same username and password combination is required as for the SkyFile software, but the web function is enabled on explicit request only to avoid any misuse. Mails for private subaccounts are not displayed for privacy reasons. Please ask the Vizada customer care for the required access data.

^ Index

To which countries and networks can I send SMS messages?

The SkyFile gateway in the land earth station has its own GSM connection and can send SMS messages to most GSM networks worldwide. There are no additional charges for this service. In a few countries SMS messages are even possible to fixed users: If the fixed telephone does not support displaying messages, the message is read by a speech synthesizer.

However, no definitive answer can be given to this question because network providers often change their roaming lists. Also, even if you can send a message to a specific network, this does not necessarily mean that you can also receive messages (answers) from that network.

Please note that a positive confirmation e-mail to your SkyFile account only says that the SMS could be sent to the local GSM network node. It does not guarantee that the message will actually arrive in the destination network or at the specified cell phone number.

The cell phone user can also answer a received SMS message by simply responding to the same GSM number where he received the message from.

^ Index

What can I do against unwanted mails (spam)?

The gateway has a built-in spam filter which will block most unwanted unsolicited e-mails. Due to the nature of such mails, however, a few spam mails may still get through. If you are frequently offended by e-mails from one specific sender, though, please inform Shamrock.

We do not recommend to forward e-mails from a mailbox at another mail provider like Google Mail, Hotmail or Yahoo to your SkyFile account. Since the servers of these services are treated as trustworthy by the SkyFile server, spam detection cannot work as good as for servers communicating directly with the SkyFile gateway.

A very restrictive way is to only allow incoming e-mails which have a specific keyword in their subject. This means that all e-mails not having this word in the subject will be deleted, and their sender gets a return mail with an error message (access denied).

Another mechanism is using a black&white list which can be managed from a previously registered e-mail address. Typically it will only consist of a white list (+) with addresses being allowed to send e-mails to your mobile account. It also allows to set a maximum size for mails coming from a specific sender. (Whitelisted senders are not required to enter a subject keyword.)

The account management at Vizada can also set file size limits for attachments in e-mails directed to your account. Especially if you are using a slow service like Inmarsat-M or Mini-M, this limit should not be set too high.

During the reception of a long e-mail you can abort the transfer of a file by pressing the "reject" button in the transfer software. This file will then be deleted on both sides, and the transfer will continue with the next file or e-mail.

^ Index

In which order do e-mails appear in the message list?

Normally the newest mails appear on top of the list. By clicking on a column title, you may revert the sort order or sort the list for other criteria, such as sender or subject.

Regarding the chronological sorting, please note this: For received mails, the "time" column shows the time when a received mail was sent, using UTC. For the e-mails sent by yourself, the local time zone is used which has been configured in Windows.

To ensure that received and sent mails appear in the correct chronological order, it is useful to configure the Casablanca/Monrovia time zone in Windows which matches UTC. If you would choose GMT/London/Dublin, the system clock would switch to daylight-saving time during summer, which is one hour back in time.

^ Index

Is it possible to use SkyFile in a network with several PCs?

Yes! Simply define the hard disk drive of the PC connected to the Inmarsat transceiver as a network resource, e.g. "c" for the local disk "C:". Please see the built-in help of Windows for details how to create a network resource. On all other PCs within the local network, the Autosync.exe program can then be launched from the network, e.g. using a desktop link, instead of installing SkyFile on all PCs.

For instance, if the machine name of the PC with the cable to the satellite transceiver is "pc1" and SkyFile resides on its local drive C:, other workstations can access SkyFile by simply using \\pc1\c\skyfile\autosync.exe as a desktop link. Alternatively, if workstations are using mapped drives like N: pointing to \\pc1\c, they can access SkyFile using N:\skyfile\autosync.exe.

Typically each workstation uses its own subaccount name and thus has its own e-mail address. It is also possible, however, to access a specific mail account from different PCs alternatively, though this should not be done at the same time.

To ensure that the mail list and the archive tree are automatically synchronized between all workstations with the internal firewall of Windows XP enabled, "File and printer sharing" must be allowed in the firewall for local LAN addresses even if the sharing service is not really activated.

If SkyFile has been configured for an automatic dial-in with a specified timing or for using subaccounts, then the transfer module is started automatically on the PC connected to the Inmarsat terminal. This ensures that internal e-mails from one subaccount to another are delivered immediately without having to go through the satellite link.

Please note that running SkyFile in a terminal server environment is not supported yet; this is planned for a later version, probably 6.20.

^ Index

Mails and SMS messages to SkyFile users

Please ask the Inmarsat user or ship owner for his e-mail address.
What sort of e-mails can be sent to SkyFile users?
Is it useful to compress attachments into one ZIP archive?
How can I send an SMS message to a SkyFile user?
Does the SkyFile gateway provide virus+spam detection?
Is there a similar software like SkyFile for my office?

^ FAQ main index - Typical return mails

What sort of e-mails can be sent to SkyFile users?

Most Inmarsat services are not as fast as landline modems or even ISDN, DSL or cable modems. To avoid high costs for the mobile users, please ensure the following things:

• Do not send HTML-formatted mails, use plain text only.
• If possible, avoid MS Word files. Use plain text instead.
• Do not cite the complete original text when answering a mail.
• Do not send attachments for fun. Their transfer can be very expensive.
• Before sending a big file, ask the recipient first if he really wants to have it.

If you receive a return mail with the text "Blocked by filter...", you should immediately check your PC for viruses. The SkyFile gateway will reject suspicious file types returning this message. However, some superfluous file types like Winmail.dat are also rejected because they contain Microsoft-specific formatting information which is not useful for other e-mail programs and would only increase transfer charges.

^ Index

How can I send an SMS message to a SkyFile user?

You can send SMS messages to SkyFile users only after you have received one from the SkyFile gateway, so you can see the GSM number of the gateway. All SkyFile users have the same GSM gateway number. There are two ways to send an SMS message:

1. You answer the SMS message, using the same cellphone which received the message. The SkyFile gateway already knows your GSM number and routes your answer to the user who had sent you a message before. No additional addressing is required. However, please do not use a colon ":" after the first word of your message in order to avoid any misinterpretation of this word as an address.
2. You want to send a message from a different cell phone or from a web-based SMS service. In this case the gateway does not know your GSM number. You will have to write the recipient's user name and a colon at the beginning of your message. Example:
   ANDREA1: Hello, thanks for your message...
   Upper or lower case is not relevant in the username.

Please note that the successful delivery of your message to the Inmarsat gateway depends on whether your local GSM provider has a bi-directional interworking agreement with T-Mobile or not.

^ Index

Does the SkyFile gateway provide virus and spam detection?

Yes! E-mails from the Internet to SkyFile users are scanned for typical e-mail worm structures using a heuristic detection, which does not rely on byte patterns and thus even detects new viruses. Mails containing such structures will be deleted without notice. In addition, some file types like .lnk, .pif and .scr or .exe files with double extensions (like test.doc.exe) are blocked in the gateway because they are typical for viruses. No return mail is created because in most cases the sender's address is faked, and the wrong person would receive the warning. However, it is still possible to send them intentionally e.g. by packing them into a ZIP file. Of course, no guarantee can be given that any type of virus will be found. Regardless of the e-mail program, users should not open any executable files which they did not expect. The SkyFile program will issue a warning when a user tries to launch a file which may contain a virus. Also, it is not possible to launch an executable file directly from SkyFile; it still has to be saved first, giving the user a chance to use his own virus scanner.

• If you are using an anti-virus software which checks open files, please either switch it to "on demand" or exclude the SkyFile folder and its subfolders from it to avoid file access conflicts. Unreadable mails or interchanged attachments might occur otherwise. The virus scanner would not find a virus there anyway because SkyFile uses encrypted mail archives. When opening a mail, its decrypted content is copied to the Windows Temp folder so the anti-virus software can scan it.

Other files like Winmail.dat are blocked because they contain Microsoft-specific text formatting information which is worthless to users of other e-mail programs. In this case the receiver is informed that the obsolete attachment was deleted. The gateway also deletes unsolicited e-mails, commonly known as spam, if they match typical characteristics, for instance a mail which is BCC-addressed and contains HTML text only.

^ Index

Is there a similar software like SkyFile for my office?

Yes, there is. The NetMail software has a similar user interface and similar functions but is not designed for use with Inmarsat transceivers but for a local-area network in an office. You should have an Internet domain of your own like "mydomain.com." E-mails are exchanged with your local provider using DSL, RAS or a router. Each workstation can have its own e-mail address. Compared to other e-mail programs, you have the following advantages when communicating with SkyFile users:

• The "remark" column in the mail list is transmitted and displayed on both sides.
• The original addressing is kept when forwarding e-mails, so you can answer the original sender.
• NetMail has many advanced functions, such as keyword-driven autoresponder and group addresses (list server).
• Similar to SkyFile, viruses and spam mails are suppressed in the NetMail server.

NetMail Light is free for up to three network users (download). The software consists of a gateway program running on one PC as a mail server, and a client software which is loaded from the server's hard disk and thus requires no installation.

Using an Inmarsat-C transceiver for e-mails

A registration at Vizada is required.
The four most important rules for Inmarsat-C
Sending Mails from an Inmarsat-C Transceiver
Why is a registration required?
Though I get a confirmation, nothing goes to the Internet
My transceiver does not have a key ":" or "@"
The e-mail I have sent contains upper-case letters only
What can I do against unwanted mails, i.e. spam?

^ FAQ main index

The four most important rules for Inmarsat-C

Inmarsat-C is a data-only service using 1200 bit/s. Most ships are equipped with Inmarsat-C transceivers since this service is the backbone of the "Global Maritime Distress and Safety Service" (GMDSS). Inmarsat-C can be used for messages with up to 32,000 characters. Via a LES (land-earth station), messages can be exchanged with modem and ISDN users, GSM (radio telephony), X.25 and Internet mail. In addition, one can receive so-called EGC messages (enhanced group calls) with weather warnings and other broadcast information. On ships small omnidirectional aerials are used, but there are also portable sets with a flat antenna.

• Land earth stations: Only use the Vizada land earth stations for sending e-mails. Even if you may get a confirmation, others will not work because they use an incompatible delivery header which the mail gateway will not understand.
• Do not forget "To:": Write To: and the Internet e-mail destination address into the very first line. Without this To:, you may get a confirmation that your message arrived at the land earth station, but the mail gateway does not know what to do with it
• Use the same transceiver: If there are two transceivers on your vessel, always use the same for sending and receiving e-mails, namely the one registered at Vizada.
• Inform your partners: When you write an e-mail to someone, ask him/her to answer as short as possible and not to attach any files. No alternative HTML format should be added; the answer should be plain text only.

^ Index

Sending Mails from an Inmarsat-C Transceiver

To send and receive e-mails, an Inmarsat user must register at Vizada to get a unique Internet address. To write a mail e.g. from a ship, the first line of the text simply must contain "To:" and the destination address, for example:
To: abcxyz.com

Please make sure that all addresses are written correctly. For example, they must not contain any spaces. If you have received a mail with From: abc <abcxyz.com>, just write To: abcxyz.com in your reply.

If the keyboard does not provide the @ symbol, an asterisk * or slash / can be used in place. Thus the example above could also read:
to+abc/xyz.com
It is possible to write several addresses into one line using , or ; to separate them. Several To, Cc and Bcc lines are possible, too, and up to 100 addresses are allowed in one mail. If no subject is given, the Inmarsat reference number will be used as the subject.

The "cs:" line is important if you are using a non-European character set in your Inmarsat-C software; cs:ru (or cs+ru) allows a Russian alphabet (Windows-1251) and cs:cn or cs+cn is for Chinese (GB2312). Without this declaration, ISO-8859-1 is assumed which is compatible with all Western European languages like English, French, Spanish, Norwegian and so on.

Then the message must be sent to the Special Access Code 29 via one of the Inmarsat land earth stations listed on the right (others will not work). The data format should be 7 bits (ASCII uncompressed). Please avoid special national symbols like "äöüéß", they are not displayed correctly. 5 bits should not be used since this would cut off some ASCII characters (especially some used in the Internet destination address), and all text would appear in upper-case letters which is difficult to read.

If the e-mail did not contain a syntactically correct addressing (no To, for instance), an error message will be returned, including the mail's reference number, e.g. (registered users only):
REF. 123456: ADDRESS ERROR
It is also possible to send an SMS message to one GSM mobile phone by writing an international GSM number behind "To:" or "SMS:", such as "To: +491717654321". Up to about 150 characters of text can be placed in the next one or two lines. Only one destination number is possible for each SMS.

Most Inmarsat-C programs have an option called "position report". Normally this option should be switched off when sending e-mails. However, the VES has no problems with up to three position report lines before the destination address. Mails containing more than three lines at their beginning will be ignored since the VES will not find the "To:" line.

^ Index

Why is a registration required?

It is possible to send e-mails even with a transceiver not being registered at Vizada by simply writing "To:" and the internet destination address into the first line of the message.

However, instead of your e-mail address your terminal number will appear in the "From:" line of such mails, and only registered Internet users can answer. Also you will not be aware of failed e-mails because you will never get a return mail in this case. (Alternatively, the Internet sender may register, so that he will be billed.)

Registration at Vizada is free of charge and ensures that you can use an individual e-mail address where your partners can send their answers to.

^ Index

Even though I get a confirmation, nothing goes to the Internet.

The land earth station only confirms that the message from your transceiver has reached the Internet e-mail gateway. This does not necessarily imply that the e-mail was addressed correctly ("To:" in the first line), that the intended recipient does actually exist, or that the message can be routed through the Internet.

Another likely cause may be that you have used the wrong land earth station. In this case, you may also get a confirmation, but the delivery header of other land earth stations is incompatible with Vizada's e-mail gateway.

^ Index

My transceiver does not have a key ":" or "@". How can I send e-mails then?

The Vizada gateway allows some alternative symbols for the ":" in "To:" and for the "@" in e-mail addresses. The following lines will all work:

First line: To: infoxyz.de To infoxyz.de to INFOXYZ.De to+infoxyz.de to info/xyz.de to info*xyz.de to andrea to: +491717654321 to++491717654321 to +491717654321

Remark: Normal line with ":" and "@". The colon is optional. Upper/lower case does not matter. "To+" allowed instead of "To:". "/" allowed instead of "@". "*" allowed instead of "@". Mail to local user Andrea. SMS message to cellphone same, but ":" replaced by "+" same, gut ":" replaced by space

By the way, it is not advisable to add a "From:" line with your name or address at the beginning of the mail. Your e-mail address is automatically added in all mails you send, and it cannot be overridden.

^ Index

The e-mail only contains upper-case letters, and national symbols are missing.

If the Internet recipient only sees upper case letters (or lower-case letters only, in some cases), you probably have used a 5-bit format for sending your e-mail. Use 7 bit to ensure that upper and lower case characters can be used.

When using national symbols like éäöüß, you will have to use the 8-bit format for sending your message because these are 8-bit characters. If you send 8-bit messages, please be aware that a DOS-based transceiver software will not be able to display all ANSI characters (used in Internet e-mails) correctly.

^ Index

What can I do against unwanted e-mails (spam)?

The gateway has a built-in spam filter which will block most unwanted unsolicited e-mails. Due to the nature of such mails, however, a few spam mails may still get through.

To avoid unwanted e-mails, you should never send mails to recipients where you do not want to get e-mails from, because your own address can be seen from your mails. You should also ask your e-mail partners not to give away your address to others without your explicit permission. And, of course, you should not enter your Inmarsat e-mail address in web forms if you cannot be absolutely sure that your privacy is respected.

To protect you from very long and expensive e-mails, the mail gateway limits the length of text messages to 7,000 characters. If you require to receive longer e-mails and perhaps file attachments, you should use free SkyFile software over Inmarsat B, B-HSD, M, Mini-M, M4, or F77.

^ Index

Mails from the Internet to Inmarsat-C

Please ask the Inmarsat user or ship owner for his e-mail address.
Sending mails to Inmarsat-C users
What sort of e-mails can be sent to Inmarsat-C users?
My mail did not arrive at the Inmarsat transceiver after 15 minutes
The original line structure is lost when the transceiver prints my mail
National symbols like äáöóüúß are lost

^ FAQ main index - Typical return mails

Sending mails to Inmarsat-C users

To send an e-mail to an Inmarsat-C transceiver, you will need to know its e-mail address, which you will get from its owner. There are two billing methods:

• If you send e-mails to the mobile number  (e.g. 491234567@...), then you will have to register at Vizada as a "registered Internet user", and you will be billed for these e-mails.
• If you send an e-mail to the username (e.g. maria@...) at the SkyFile domain, the mobile user will be billed for it.

Optionally it is possible to write a format string behind the username, e.g. 491234567.tlx@... or maria.tlx@..., in order to control what is actually sent and how many bits are used for each character:

To send a message with 5 instead of 7 bits per character, saving about 15 % cost, you may alternatively write 5BIT anywhere in the subject. With 5 bits only, all upper-case letters are converted to lower case, and some symbols are replaced by similar characters due to the limited character set of the 5-bit alphabet, so mail addresses are not always displayed correctly.

Note that an Inmarsat-C user does not use a typical e-mail program such as Microsoft Outlook, but a specialised Inmarsat program provided with the transceiver, containing a simple text editor. This editor is unable to decode multipart messages with an alternative HTML text, appended graphics or binary files. So the message must be sent as plain text only. Make sure that an HTML option is switched off in your mail program. Since a typical 500-character message costs about 4 US $, keep your mail compact. If you answer a ship's mail, save costs: Do not send back the referenced original message. Hopefully the sender still knows what he wrote.

Internet mails to Inmarsat-C transceivers are limited to a configurable length. This protects their users from long, expensive, and possibly unwanted mails. In case of a problem, you will receive a return mail with an error message. Otherwise, if the transmission of your e-mail via satellite was successful and confirmations are activated for the specified user, you will get a notification some time later:
Message to (user name) of (date): Ref. (LES reference number)

^ Index

What sort of e-mails can be sent to Inmarsat-C users?

Please switch off the "HTML" option in your e-mail program. The HTML alternative format would not arrive. Send your e-mail as plain text only. Also avoid entering the text in other applications like MS Word and then pasting it into the e-mail program; this often results in a bad formatting or in special symbols which cannot be displayed on the Inmarsat transceiver.

Do not add file attachments when sending an e-mail to Inmarsat-C. The transceiver would not be able to decode or store these files. Thus the gateway cuts them off to avoid unnecessary transfer costs. Also, do not use electronic signatures like PGP because this data cannot be decoded or even verified by the Inmarsat recipient.

If your message contains national symbols like éäöüß, the gateway will convert them to similar ASCII symbols so that the e-mail can be transmitted using 7 instead of 8 bits per character. (Most transceivers do not print 8-bit messages automatically so the recipient would probably not notice your e-mail.)

The maximum length of the text body of mails to Inmarsat-C transceivers is limited to protect the receiver from high costs. You will receive an error message if your mail was too long.

^ Index

My mail did not arrive at the Inmarsat transceiver even after 15 minutes!

The time required to send an e-mail to an Inmarsat-C transceiver depends on several factors:

• Frequency of mail transfers between your e-mail program and your local mail system (if any)
• Frequency of mail transfers between your local mail server and your Internet provider
• Time required at the Vizada gateway to retrieve your mail from the Internet
• Time required at the Vizada gateway to queue the message at the land earth station
• Time required at the land earth station to locate the receiver and to send your message
• If the receiver is logged out or busy: Later retries for delivering your message

Typical values are 5 to 60 minutes. It is possible to activate confirmation e-mails at the Vizada gateway, so you will get a return mail as soon as your message was sent to the land earth station.

^ Index

The original line structure is lost when the transceiver prints my mail.

Inmarsat-C transceivers can only display up to 78 characters per line, sometimes even only 64. Being aware of this, you should try not to write more than 64 characters into each line of your e-mail.

Another typical reason is that you were using a text processor like MS word and then pasted the text into the e-mail program. This often results in all line feeds being lost, so that your mail will contain one single (very long) line. When saving a message in a text processor, use "Text with line breaks".

Using the Windows clipboard often gives better results than exporting the text to a file and then re-importing it into the e-mail program.

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Why are national symbols like äáöóüúß lost when I send an e-mail to Inmarsat-C?

While it is technically possible to send e-mails with 8 bits per character, most Inmarsat-C transceivers would not print these automatically.

This is why the mail gateway will convert äöü to their 7-bit equivalents aou (not ae, oe, ue, because this would create problems with the formatting of tables in the text). The same is true for other national symbols like á, à, ó, ò, ß and many others.

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