Comtech EF Data FX Series Administrator Guide - Manual (Page 26)

Comtech EF Data / Stampede
FX Series Administration Guide - Version 6.1.1 26
Chapter: Overview - FX Series
Section: Single-Sided Solution
MN-FXSERIESADM6 Rev 5
1.3.3 Connection Management
Connection management removes the burden of establishing and terminating TCP connections from the
web servers, allowing the server to handle more traffic. Stampede manages network connections in
several ways to optimize the flow of data and reduce the impact on the network, application servers and
end-user devices. The FX Series appliance maintains a consistent pool of connections between itself and
the servers. The servers are then offloaded from managing the connections, and are isolated from
inadvertent session disconnects.
With Stampede's FX Series Remote appliances working with the FX Series head-end appliance, a
persistent connection between the client and server is always maintained, even when the browser may
close and reopen a session. These sessions are also multiplexed across multiple connections, improving
throughput and response time. This persistent connection is extremely important for AJAX and Web 2.0
applications which constantly open and close sessions as they poll and access various Web services.
Stampede eliminates this potentially network intrusive overhead.
1.3.4 QoS with ACM option
The Quality of Service Function with ACM option is intended to work with EF Data modems that support
ACM. The FX Series ADC and Remote have the ability to read the current data rate from the modem, and
will adjust the output data rate to match the modem data rate. The FX Series data rate is calculated
based a per Ethernet frame basis.
The FX is also designed to work with the modem in a 1:1 Redundant with fail over mode and work with
the modems when they are in a 1:1 redundant configuration.
Output Data Rate
All data rates are Ethernet frame rates. The total data rate is a parameter that can be set, or
under the optional ACM mode, can be updated dynamically and continuously from the modem in
the link.
Traffic Classification
Traffic can be classified on combinations of Protocol, VLAN, Source/Destination IP Port number,
Source/Destination subnet,
MPLS labels/EXP and DSCP bits. Classified traffic is directed into
specified Queues. Queues are assigned priority.
Traffic shaping
Traffic is shaped using drain algorithms on the specified queues. Queues of equal priority are
treated in a fair-weighted manner. Connections within a specified Queue are also treated in a
fair-weighted manner.
The drain algorithms are strict priority or Min-Max. In Strict Priority, available bandwidth is
allocated on the basis of priority.
Min-Max gives more control. Bandwidth is allocated up to a committed information rate based
upon priority. Once the committed information rate is reached for all classes, excess bandwidth
is allocated based on the same priority, up to a defined maximum for each Queue.
1.3.5 GZIP Compression
The most common use of compression in Web environments is accomplished by enabling GZIP
functionality at the Web server. GZIP compression is handled on-the-fly from the servers to the clients.
This reduces bandwidth consumption and improves application delivery and client response time. The FX
Series uses GZIP compression to reduce the payload size to deliver more data across the satellite link,
enabling more applications to be delivered and the ability to support more users. GZIP compression