• United States
Neal Weinberg
Contributing writer, Foundry

ITWorx NetCelera and Packeteer PacketShaper Xpress

Sep 02, 20033 mins
Enterprise Applications

* The Reviewmeister continues his compression obsession

The Reviewmeister is developing a compression obsession. This week, we analyze three more compression products.

Let’s start with the ITWorx NetCelera. This is a LAN-based network compression product.

It includes two 10/100M bit/sec ports – a local one connected to the switch and a second, labeled remote, that is connected to the router. NetCelera scales to speeds of up to 45M bit/sec. NetCelera boasts a quick installation process and made a very strong performance showing in our tests, particularly with TCP/IP traffic.

Full-blown configuration and ongoing management are accomplished using a Web-based GUI, and a command-line interface (CLI) is also available. Both methods require secure connections. Access lists might be employed to prevent unauthorized connections to the device, but we did not test this feature. Logging is accomplished via SNMP and syslog support.

ITWorx says NetCelera works at the session layer of the Open Systems Interconnection model – this device inspects flows at Layer 5 (before they are merged at Layer 3 into one IP stream). The other devices we tested can do what is termed packet aggregation: Rather than compress and pass each packet along with an individual IP header, these devices can wait a number of milliseconds, compress each packet and then pass an aggregated packet with one header, thereby saving space. Because NetCelera “understands” TCP, there is no need for it to implement this mechanism.

But we have to note that NetCelera does not support compression of UDP traffic and simply passes it through the device unchanged. Also, pass-through (no compression) of UDP traffic meant that the VoIP test performed on other devices was not conducted with this device, because the G.711-based VoIP calls are UDP-based.

Also, we were disappointed that the system did not include a central management system or QoS features. ITWorx said it will add features that address these concerns within the next six months.

* Packeteer PacketShaper Xpress 2500 and 6500

Next, we obsessed over Packeteer’s PacketShaper. This is a LAN-based QoS product, but with the purchase of Xpress software, compression capabilities are added to the device. The PacketShaper 2500 and 6500 each include two 10/100M bit/sec ports, one labeled “Inside,” the other labeled “Outside.”

The inside port is connected to the switch, while the outside port is connected to the router. The 2500 supports configurations ranging from 2M to 10M bit/sec, while the 6500 scales to 100M bit/sec. If you’re looking for the best mix of compression and QoS features, this is your box.

The PacketShaper Xpress software is the only product tested that lets the operator choose which compression algorithm to use. By default, the system uses Predictive 2, a two-pass predictive algorithm. It compresses only traffic deemed capable of incurring a significant compression ratio.

Ongoing configuration and management is performed through a GUI, but a CLI is also available. In our testing, PacketShaper had good performance with TCP and UDP traffic, and voice over IP (VoIP).

What really separates Packeteer from the rest of the pack is the maturity of its QoS features – they had no problem protecting the VoIP call by placing it into a prioritized queue.

The only problem we ran into during testing was the same problem we saw during our QoS testing with the device last year – it might take a few minutes for low flow-count traffic to be recognized by the PacketShaper’s classification engine.

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