Allowing Multipart Transfers (COMB Command) on the Site

EFT supports multi-part transfers from advanced FTP clients such as CuteFTP. The user must have appropriate privileges and be authorized to connect multiple times concurrently. The connecting client takes care of most details, including splitting the file apart, sending the multiple parts, and then requesting that the Server to join them again upon receipt.

To allow or block multipart transfers

  1. Open the FTP Settings dialog box.

  2. Do one of the following:

  3. Click OK to close the FTP Settings dialog box.

  4. Click Apply to save the changes on EFT.

Refer to the Globalscape Knowledgbase article at http://kb.globalscape.com/KnowledgebaseArticle11120.aspx for details of enabling the COMB command via a registry setting.

How does the COMB command work?

The COMB command joins the parts back together. The benefits of segmented (multi-part) and concurrent delivery for accelerated transfers include:

The COMB command is a proprietary command and is not defined nor endorsed by any FTP-related RFC; however, the command can be integrated with other servers using the following syntax:

COMB <TF> <SF 1> ... <SF n>

where

<TF> is the path to target file, which will contain the combined data from the source parts.

<SF #> are the source files (parts).

Which means combine n source files (SF 1...n) into one file (TF).

Notes regarding the COMB command:

Examples of using the COMB command:

The following table presents the support that is available for each protocol:

Protocol

Upload to EFT

Download from EFT

EFT Push (offload/upload)

EFT Pull (retrieve/download)

HTTP

Not supported

EFT does nothing to prevent a client from using whatever techniques it wants to perform a multi-part transfer. For example the client could use the REST command to resume multiple segments of the same file then rejoin upon receipt.

Not supported

Not supported

HTTPS

Not supported

Not supported

Not supported

FTP

Remote client must issue COMB command to EFT to join the uploaded parts.

Registry enabled;

Remote server must support COMB command. Otherwise will not work.

Registry enabled;

Does NOT require remote server to support COMB. Uses REST (resume) at byte offset.

FTPS

SFTP

Not supported

Not supported

Not supported

AS2

Not supported

Not supported

Not supported