Subject: [ANN] Stalker Announces the First Dynamic Cluster
From:  Ali@stalker.com (Ali Liptrot, Stalker Software, Inc.)
Date: Fri, 28 Jan 2000 18:09:24 -0700
Organization: Stalker Software, Inc.

FOR IMMEDIATE RELEASE

Stalker Announces Super-Symmetric Dynamic Cluster Version of CommuniGate Pro

Key Features: Cluster Support - Full Redundancy, Load Balancing
	      Multi-platform Support 
              Industry-strength, highly scalable      
              Administration via the Web 
              Extensive multi-domain support 
              Unique IMAP multi-mailbox features 
              HTTP access to E-mail, built-in Web Mailer 
              Extensive Anti-Spam techniques 
              Mailing Lists with Web Access and Interactive Archive Search
              LDAP and ACAP Support
              Personal Web Pages with automated publishing
             

MILL VALLEY, CA - February 1, 2000 - Stalker Software, Inc. today announced
the Super-Symmetric Dynamic Cluster version of CommuniGate Pro. The high-end
CommuniGate Pro messaging system is available for Unix, Linux and NT platforms
and can serve 200,000 accounts on single server installations and can now
support several million accounts on heterogeneous multi-server Clusters.

In 1999 over 4.5 million CommuniGate Pro accounts were licensed to small and
mid-size ISPs migrating to the CommuniGate Pro platform to benefit from its
unmatched stability and performance.

In the same period of time, over 1500 CommuniGate Pro servers were installed
at corporate, government, and educational sites that chose CommuniGate Pro for
its standards-compliance and extremely rich feature set.

The combined power and performance of CommuniGate Pro is now brought to the
carrier-grade level with the Dynamic Cluster release.


Super-Symmetric Dynamic Clustering

CommuniGate Pro is the first product on the market providing true message
clustering based on account-level synchronization. Before the CommuniGate Pro
Dynamic Cluster release, large ISPs had to use the solutions that relied
completely on OS and FileSystem-level locking. Those solutions were advertised
as scalable and reliable, but suffered from instability and performance drops
inevitable for that type of design.

While Web Interface to E-mail became more and more popular, lock-based
messaging servers either failed to provide any Web Interface at all or
provided limited versions of non-native Web Interface at a cost of serious
performance degradation.

The innovative account-level synchronization scheme used in CommuniGate Pro
Cluster is based on a TCP/IP protocol and provides non-locking multi-access to
all mailboxes served by the Cluster.

Released from file-locking duties, the same storage devices (file servers) can
now be used to handle much larger number of accounts than they could process
with older solutions, with increased stability and performance.

Frontend-Backend Topology

The CommuniGate Pro Cluster can include a set of front-end servers taking the
load off the back-end servers by performing all mail relaying operations,
SSL encryption/decryption, and some other operations. Since only front-end
servers are exposed to the Internet, they protect the back-end servers from
all possible types of TCP/IP attacks (including DoS attacks).

Front-end servers have no access to the account information and protect the
site from any type of server OS exploits.

Frontend Load Balancing and Redundancy

While the frontend servers are at a higher risk of failure, the site survives
till at least one front-end server is in operation. Front-end servers can be
added and removed from the cluster at any moment, with no switch-off/recovery
operations required.

The load can be balanced between frontend servers using traditional traffic-
based method (as Layer4 Switches) or using DNS round-robin mechanisms.

Back-end Load Balancing and Redundancy

Sophisticated mail servers can experience heavy load without producing a lot
of traffic (for example, there can be many search operations in progress). To
provide the best site performance, front-end servers distribute operations
between back-end servers based on the real load, not on the traffic volume.

All back-end servers provide access to the same domains and accounts, and any
back-end server can be switched off at any time and a back-end server can be
added to the Cluster at any time, too - without stopping the site.

The CommuniGate Pro Dynamic Cluster synchronization protocol provides the
auto-cleanup methods, so if a back-end server fails, there is not need to
manually clean any resources it could lock at the time of the failure.

Transparency

CommuniGate Pro is well known for its clean and clear WebAdmin interface for
both server and domain (delegated) administration. The CommuniGate Pro Cluster
is completely transparent for both users and administrators, and presents
exactly the same interfaces as it does on single-server sites. Administration
commands are automatically directed to the proper server and updates are
automatically propagated to all servers in the Cluster.


Try Before You Buy

The CommuniGate Pro Free Trial Version is available at
    .
See  for the details.

The updated versions (both betas and finals) are posted on a regular basis.

Discuss the Communigate Pro-related issues at
    

The Dynamic Cluster support requires the Site and Cluster License Keys.
Contact Stalker at 800-262-4722 or sales@stalker.com to learn more about
the licensing policies.


					 ###
Stalker Software, Inc. develops and distributes mail servers, networking and
communication software. The company was founded in Europe in 1991 and opened
its U.S. offices in 1993 at 655 Redwood Highway, Suite 275, Mill Valley,
Calif. 94941. For more information about Stalker Software, Inc. and its
products, please contact Alice Liptrot, director of sales and marketing,
at (800) 262-4722 or (415) 383-7164. She can also be contacted by fax
at (415) 383-7461 or E-mail at .
Visit the Stalker Software web site at .