SSE Service Usage FAQ

This FAQ groups common questions that SSE registered users may have regarding the usage of SSE services, providing answers for them.



Question: I have placed an order on a service but it is reported as failed. Is there a bug in the service or in the SSE?

Normally no. Orders to a service can fail for several reasons and often this does not mean that there is a problem with the service.

Some of the reasons for a failed order are:

> the product that you are trying to order is not available. You can try to order other products.
> the input provided by you (e.g. FTP link, product format) is incorrect. See questions 2 and 3 in this FAQ.
> there is a temporary network problem that affected the order processing. In this case you can retry at a later date.

Question: The service I am trying to use requires that I provide a link to a file in an FTP server. What do I need to do in order to be able to use this service?

You need to place the file you wish to process in an existing FTP server accessible by the SSE servers through the Internet or, if don't have access to such a server, configure one and place the product there. An example of software that you can use for this is FileZilla Server, which is only available for Windows. If you are on Linux/Unix you can use vsftpd which is normally already included in most Linux distributions. Any existing firewalls on your side must be correctly configured to allow the connection from the SSE servers.

You also need to make sure that you have the product packaged in the exact way that the service requires it (e.g. several files inside one zip file). Read the service's SLA or abstract to understand how you should package the product. Some services include an in-context table that can help you determine the correct format.

Question: My FTP server seems to be correctly configured and available but the service requiring the FTP link reports the order as failed, saying that it is unable to download the product from the FTP server. What should I do?

The generic format for an FTP link is:
where username and password are empty by default and port defaults to 21. For example, the link
would cause the service to connect to port 21 of providing no username and no password, while the link
would cause the service to connect to port 2121 of providing "foo" as username and "bar" as password.

When all existing firewalls are well configured to allow the connection from the SSE servers to your FTP server and the service is still unable to download the product, this normally means that:

> either the username or the password, or even both, are wrong.
> the server port is wrong (this can happen for example if your server is not running on port 21 and you forget to explicitly define the correct port).
> there is a typo in the server address or the path to the filename. In particular, you should remember that FTP links are case-sensitive - Image is different from image - and that certain characters - l - can be easily mistaken for others - 1 - using certain fonts.

If you are sure that your link is correct - for example if you can download the file using another FTP client and the exact same link - but you still cannot use the service, then contact the Service Provider directly or us.

Question: I am an ESA CAT-1 user, do I need to register on the SSE Portal to use SSE services?

In most cases, no.

Approximately 2000 ESA CAT-1 users are automatically registered on the SSE and they can use the same username and password that they use for EOLI to access the SSE and even the Join and Share area. Moreover, many of these users are also automatically authorized to access certain SSE CAT-1 restricted services (e.g. MERIS RR Cloud-free Product for Cat-1 Users and MERIS Cloud-free Subscription Service), meaning that they can use those services without having to go through the usual access request process.

If you are an ESA CAT-1 user and you cannot login on the SSE or the Join and Share Area, you can either create a new SSE account or contact us so that you are registered.

Question: I placed an order on an SSE service. How can I check if it has been processed?

When you confirm your order information and then place the order on an SSE service you are presented with the Order Result page.

When the order is synchronous, the order result will be immediately available on that page. When the order is asynchronous, which is often the case because the service requires some time to process it, the page will show you the Order Result as pending. It may stay like that for hours and even days.

While you can refresh the page continuously until the result is ready, probably a better option is to do something else and check the order back later. The most common way to do this is by clicking the Order List link on the SSE home page after you login. The Order List page will always display all your orders to different SSE services in chronological order, with the most recent appearing first. Clicking the OrderId in which you are interested will show you the same Order Result page that you saw after placing the order.

Alternatively, if you use a service that can be used anonymously (i.e. without logging in), you can place the order and write down the OrderId. With this, afterwards, once again without logging in, you can click the Order Information link on the SSE home page, enter the OrderId in the corresponding text field and the Order Result page will be shown to you. However, in this case, you should know that your order result will be available to anyone, anonymous or registered SSE user, if they know the OrderId.

Question: The Order result page provides an ftp account but i'm not able to download the file. What can I do?
Answer  This may depend on the ftp client configuration, and in particular the connection mode. It is recommended to configure it as Active. To do this with IE select Tools->Internet Options and then select the Advanced tab. Uncheck the checkbox "Use Passive FTP (for firewall and DSL modem compatibility)".
Question: When searching for services or organizations, I get too many results and several of these are quite unspecific. What can I do to improve results?

The reason for this is that the SSE search engine uses the "OR" operator on the keywords by default, i.e. it displays all the results that match one or more of the keywords you have entered. For example, when you search for

MODIS Catalogue

you get all results that contain MODIS, all results that contain Catalogue and all results that contain both MODIS and Catalogue. This means that if you are searching for a service offering a MODIS Catalogue, you will actually find it in the middle of several results which correspond to generic catalogues, of all kinds of data, MODIS or not.

To get better results, you need to be aware that the SSE search engine relies on the open-source Apache Lucene project, which makes available powerful, and yet relatively simple, syntax to perform complex and very refined searches.

This syntax is extensive and you can find a thorough explanation on the SSE/Apache Lucene help pages. In here, we just aim to give you a couple of useful examples of how to use it.

Example 1 (exact match):

"modis catalogue"

By including the keywords inside quotes (""), you will only get results that include the exact phrase inside the quotes. For example, you will get services with title "MODIS Catalogue" and services with an abstract including "This service offers a MODIS Catalogue with data since 2008..." but you won't get results for services with a title like "MODIS Data Catalogue" or services with an abstract like "This service offers MODIS data by means of a catalogue...". This kind of search is quite restrictive but useful in cases where you know exactly what you are looking for.

Example 2 (AND operator):

modis AND catalogue

Using the AND operator, you change the default behavior of the SSE search and will only get results that include all keywords surrounding the operator. With this search, you will still get results for services with title "MODIS Catalogue", services with an abstract including "This service offers a MODIS Catalogue with data since 2008..." but now you will also get results for services with a title like "MODIS Data Catalogue" or services with an abstract like "This service offers MODIS data by means of a catalogue...". On the other hand, you will not get results for services with title "MGVI Catalogue" or services with an abstract like "This service offers MODIS data..." that do not include the word "catalogue". This kind of search is less restrictive than an exact match but gives you much more specific results than those obtained by using the OR operator.

Example 3 (wildcards):


Using the "*" wildcard character, you will have a lot of flexibility, as you will actually be searching for several words using just one string. With the example above, you will get all results that include the words catalog, catalogue, catalogues, cataloging, etc.

This is just to give you a flavor of what you can do with the syntax. To learn more (including the NOT, +, ?, etc. operators), you should really check the SSE/Apache Lucene help pages.

Finally, note that all searches in the SSE, by default, are case-insensitive.