Historically, the benefits of load-balancing and application acceleration, while clearly advantageous to any user who accesses data and applications stored in a data centre or server farm—and who doesn’t—have been restricted to Enterprise and above.

However, with its ALB-X product, jetNEXUS made these features available in every format from a physical appliance through virtual appliance, down to ISO?an image sitting on a CD or USB key that turns pretty well any server into a load-balancer. Now the company has introduced v2 of its product, with the additional features available in all three product formats.


Here we focus on what we see as the key features being offered by jetNEXUS’ ALB-X v2 that are of real use by a broad range of customer types to provide load-balancing and application delivery control. With the ALB-X VA, the virtual appliance version of the ALB-X product, this offers the full range of ALB-X features, just in a virtual appliance.

The build includes a custom kernel operating system integrated with the ALB-X software. The virtual appliance runs on many desktop environments as well as the increasingly ubiquitous VMware ESX server. The installation is simple and quick and, importantly, requires no experience of the underlying operating system.

The entire configuration can be carried out via the jetNEXUS Web admin console or the jetNEXUS discovery application. For the ISO version, installation is even more straightforward and almost completely automated.

New to v2 of the product, in addition to significant performance improvements on the hardware side, a new GUI replaces the old version with a far sharper appearance than previously.

Routing options are also improved significantly so that multiple interfaces and combination can now be used to provide both more flexibility and better performance than before. An important addition is flightPATH?a powerful routing engine which enables clients to create and implement bespoke application rules.

The aim here is to considerably improve day-to-day traffic management for clients, giving them greater control and intelligence in managing service delivery. This is especially crucial when managing online applications and ecommerce sites. Due to the configurable nature of flightPATH, rule options are infinite but some common uses are to, for example, block unwanted requests, rewrite user requests, control spiders and fix broken URLs. FlightPATH can be used to modify incoming and outgoing* HTTP/S content and requests.

As well as using simple string matches such as “starts with” and “ends with,” powerful Perl compatible regular expressions can also be implemented for more control. In addition, custom variables can be created and used in the “action” enabling many different possibilities (see illustration below).

In terms of what else ALB-X v2 offers, let’s start with the obvious. Performance is clearly a primary requirement for load-balancing and application delivery. For this reason, the ALB-X includes Content Caching?a feature that has typically only been found on dedicated devices or top end application delivery controllers, and then typically as a high-cost option.

Is it effective? Well, one e-commerce customer of jetNEXUS has reported that it now serves 94% of all its content from the cache. Not only does this improve performance but also reduces the number of back end servers and subsequent licences required.

Layer 7 load balancing is fundamental to application delivery control, operating, as it does, at the application protocol level. Again, this was a feature absent on lower-priced devices until the likes of jetNEXUS introduced at an entry-mid level. Key to Layer 7 Load-Balancing is that the device recognises the type of data it is processing?HTTP and HTTPS where the ALB-X is concerned, and consequently allows for many features that are not possible at lower-level load-balancing such as URL switching, cookie-based persistence and request scanning.

In conjunction with Layer 7 optimisation, the ALB-X also supports Connection Management. This is used to optimise the performance of TCP/IP in that it terminates the thousands of TCP connections applications generate at the device, then consolidates them to send far less (effectively bundled) connection requests to the Web server. TCP connections are one of the primary killers of server performance placing, as they do, enormous stress levels on the server pool. Connection Management is therefore a fundamental requirement of high performance load-balancing and application delivery.

How do you know if all servers in the pool are operating in full health? Unless you monitor the server pool, it is impossible to know, meaning you could be forwarding large amounts of traffic to a server that is experiencing operational problems, or is simply saturated. For this reason, the ALB-X performs a series of server health checks, from simple ping and TCP tests to full web GETs, to ensure every server is performing as it should.

Another fundamental of data performance optimisation is accelerating Web traffic. The ALB-X uses jetNEXUS’ compression algorithm to deliver compressed, optimised content in a form that is readable by the browsers. This acceleration is tuneable via the ALB-X management GUI and rule of thumb guidelines are provided by jetNEXUS to aid with optimising configuration for each particular environment.

Rule-based compression detects and compensates for browser behavioural differences and defects, therefore guaranteeing that accelerated pages can be displayed correctly by the client’s browser. It has the ability to accelerate most content including Javascript, AJAZ, XML and other types, as well as Office documents (e.g. DOC, XLS, PPT, etc.) and configurable MIME types.

It can act on HTTP headers?POSTS, SOAP, HTML, JavaScript, etc and has the ability to accelerate HTTP 1.1 through HTTP 1.0 Proxies and Caches (e.g. Squid, MS ISA, etc.) and can accelerate through Personal Firewalls (e.g. Symantec, MacAfee, etc.). Streaming compression is also supported.

In conjunction with connection control, terminating SSL (https) requests at the load-balancer, rather than at the server?SSL offload in other words?massively reduces the performance impact on the server pool. Past testing has shown that https traffic can generate 10 times more load on the server than regular http traffic.

Therefore, by terminating it at the ALB-X device, not only is server performance dramatically improved but it also means that?in some cases?server consolidation can take place, reducing costs further. This also has major management benefits, both from an operational and cost perspective.

A number of reporting and logging features are available with the ALB-X. Reporting is where many network devices typically come unstuck?if it is impossible to get decent statistics out of the device then how do you know if it performing as well as it should be? For example, you can capture live traffic stats to see what levels of content compression, throughput rates and cache performance and view it real-time.

Equally, you can monitor the status of the ALB-X device itself. As well as being available in tabular format, a “dashboard” can be viewed, providing a graphical analysis of current device status, with alert logs and compression performance. In addition to the aforementioned logging, statistics and reporting on inbound and outbound traffic in real-time, jetNEXUS provides extensive alerting facilities?for example, via an email alert?as well as full SNMP support.


With the new release of ALB-X, jetNEXUS has significantly improved upon what was already an incredible amount of features for the money compared with most rival technologies. With pricing starting at £2,995 (ex. VAT) for the virtual/ISO versions and £3,495 (ex. VAT) for the physical appliance, the “bang per buck” quota is well and truly enforced here. Moreover, a little birdie tells me that software-based WAN-based Web acceleration capabilities are just around the corner, which will turn the product into the most comprehensive technology of its type.