Network Entrez is now more firewall-friendly

Jonathan Epstein epstein at gold.nlm.nih.gov
Tue Dec 5 15:07:04 EST 1995

For the uninitiated, Network Entrez is a client/server retrieval system
which includes access to the public sequence databases as well as 3-D
structures, a genome database, and portions of MEDLINE.

Many people use 'Network Entrez' behind their institutional firewall, with
mixed results to date due to incompatabilities between firewalls and the
design of Network Entrez.

As of Network Entrez release 4.013, which is currently on
it is possible to reverse the direction of the client<->server connection
in a manner which is more favorable to firewalls, namely, by causing
the client to connect to the server instead of vice versa.  The default
behavior is still for the server to connect back to the client.  To
override this behavior you can either
  (a) select the "Outgoing connections only" checkbox on the second screen
      of the netentcf configuration program
  (b) manually set DIRECT_SVC_CON=TRUE in the [NET_SERV] section of the
      NCBI configuration file on your system.

It is our intention to continue to support the UNIX SOCKS capability of
Network Entrez which was added in mid-1994.  We have no plans to add
any SOCKS capability for non-UNIX platforms.  Note, however, that on Windows
platforms it is possible in principle for a SOCKS-friendly WinSock
implementation to effectively provide SOCKSified Network Entrez access when
used in combination with the DIRECT_SVC_CON mode described above.

The next version of the NCBI toolbox
will contain this new functionality, and naturally we encourage you to
develop client software which makes use of this functionality.
You may also wish to compile Network Entrez for yourself from source
code if you have an institutional firewall which requires special

Please direct general Network Entrez queries to net-info at ncbi.nlm.nih.gov,
and general NCBI toolbox questions to toolbox at ncbi.nlm.nih.gov.


- Jonathan

Jonathan Epstein                                epstein at ncbi.nlm.nih.gov
National Center for Biotechnology Information   Phone: (301)496-2477 x254
National Library of Medicine                    Building 38A, Room 8N805
National Institutes of Health                   8600 Rockville Pike
                                                Bethesda, MD 20894

More information about the Bio-soft mailing list

Send comments to us at biosci-help [At] net.bio.net