Aspera

Aspera's fasp transfer technology eliminates the fundamental bottlenecks of conventional file transfer technologies such as FTP, HTTP, and Windows CIFS, and speeds transfers over public and private IP networks. In addition, users have extraordinary control over individual transfer rates and bandwidth sharing, and full visibility into bandwidth utilization.

Installing Aspera:

Please go to the Aspera website and download the Aspera Web Connect web browser plug-in. Once installed, you'll find the command line ascp binary at the following locations:

Windows

<INSTALLDIR>\Aspera\Aspera Connect\bin (e.g. C:\Program Files\Aspera...)

Linux

/home/<USERNAME>/.aspera/connect/bin/ (e.g. /home/user/.aspera...)

Mac OS

/Applications/Aspera Connect.app/Contents/Resources

Transferring Files To/From the Aspera Server:

Once the Aspera client has been successfully installed, transfers to and from the Maryland Genomics Aspera server can be executed with your Maryland Genomics Aspera username and password, which you will receive via your data delivery email.

Downloading Files via Web Browser:

Point your browser to https://grc-aspera.igs.umaryland.edu/ . You will be prompted for your Aspera server account username and password. Upon authentication, you will be presented with a directory listing of your available files. If you have not installed the Aspera Connect plug-in as described above, you will be prompted to do so. Click the checkboxes next to each file you wish to download and then click the Download button. Aspera Connect will initiate the download.

By default, the Aspera Connect plug-in limits transfers to 10 Mbps. This may be increased by clicking the (~) button on the download dialog and dragging the maximum bandwidth bar to the top. Click here for an example.

Please Note: Web browsers and plug-in technologies evolve rapidly and not all browsers are supported by Aspera. Where possible, we recommend using the ascp command line utility for downloads. If you have problems with a web-based download, please contact us.

Downloading Files via Command Line (ascp):

Upon downloading you will be prompted for your Aspera server account password.

Downloading with the ascp client uses the following syntax:

$ ascp [-l <Maximum download speed>

        -m <Minimum download speed>

        -k <resume level 1,2,3>

        -Q

        -T]

        <username>@grc-aspera.igs.umaryland.edu:/<path to desired files on GRC server> /path/to/local/download/area

All parameters between the [ ... ] brackets are optional parameters that are described below:

l Allows for the user to set a maximum download speed that aspera should attempt to stay at or below for the duration of the transfer. A speed in Megabits must be provided with this flag. Our maximum bandwidth is 1024 Mbps.
mAllows for the user to set a minimum download sped that aspera should attempt to stay at or above for the duration of the transfer. A speed in Megabits must be provided with this flag.
kAllows for the resumption of an interrupted download based on the level selected. We recommend the -k 1 level.
QTurns adaptive rate on. Adaptive rate controls the speed of aspera with a goal of not dominating the bandwidth available. Very useful on busy networks that may have other transfers ongoing.
TTurns encryption off. Turning encryption off will allow for a maximum throughput transfer but should not be provided if data being downloaded is sensitive.

An example invocation of a file being downloaded from the server can be found below:

$ ascp -l 500M -k 1 -QT grcguest1@grc-aspera.igs.umaryland.edu:/YourData.tgz /home/user/data/ Aspera would attempt to keep the maximum transfer speed at 500 Megabits per second and would not encrypt the data being sent to the IGS server. Adaptive rate flow is turned on so that aspera does not monopolize the network bandwidth. The YourData.tgz file will be downloaded to the local /home/user/data folder with the execution of this aspera command. Downloading the entire directory of files requires no changes in syntax: $ ascp -l 100M -k 1 -QT grcguest1@grc-aspera.igs.umaryland.edu:/ /home/user/data

Uploading Files:

Upon uploading you will be prompted for your Aspera server account password

Uploading files can be achieved using the same download syntax described above:

  ascp [-l <Maximum download speed>

        -m <Minimum download speed>

        -k <resume level 1,2,3>

        -Q

        -T]

        <path to file or directory> user@grc-aspera.igs.umaryland.edu:/

The only visible change here is supplying a file prior to providing user@grc-aspera.igs.umaryland.edu:

$ ascp -l 100M -QT /home/user/genomes/e_coli/e_coli.tar user@grc-aspera.igs.umaryland.edu:/

Here the e_coli.tar file would be uploaded to the user folder on the server. Uploading a directory of files would not require any changes as aspera will recognize a folder is being transferred and will recursively step through ensuring that all files found in the directory are transferred.

   $ ascp -l 100M -QT /home/user/genomes/e_coli/ user@grc-aspera.igs.umaryland.edu:/

Firewall Considerations and other helpful links:

Firewall requirements and considerations:: https://www.ibm.com/support/pages/firewall-considerations
Providing credentials via environment variable for scripted downloads:: https://www.ibm.com/support/pages/how-provide-credentials-command-line-transfers
Resuming interrupted transfers:: https://www.ibm.com/support/pages/resuming-file-transfers-ascp

Aspera Connect User Guide for Windows:: https://www.ibm.com/docs/es/aspera-connect/4.2?topic=aspera-connect-user-guide-windows
Aspera Connect User Guide for MacOS:: https://www.ibm.com/docs/en/aspera-connect/4.2?topic=aspera-connect-user-guide-macos