Citrix has 'significantly enhanced' its Branch Repeater, a box used to accelerate the delivery of virtualised applications to users in branch offices.

Citrix is an application delivery specialist, and its Branch Repeater 5 is a 'key component' of the Citrix Delivery Center product family, which is the catch-all name for a group of products made up of XenServer, XenDesktop, NetScaler and XenApp.

Branch Repeater is essentially an appliance that looks to deliver LAN-like application performance over the WAN, by making improved use of existing network bandwidth. With Branch Repeater 5, Citrix is hoping to improve the end user experience in a local branch office, by improving the delivery of voice, video and 3D graphics to virtual desktops.

This is important, as Citrix feels that many businesses have already achieved cost savings by centralising their applications and desktops in data centres using virtualisation, but are now looking to consolidate or remove the local servers that provide services in the branch office.

Branch Repeater is useful for streamed applications, as it accelerates application delivery to the branch and lessens the need for a local server, the company said.

Citrix also said it accelerates the launching of the application, as well as its printing and file transfers, by compressing, de-duplicating, staging and prioritising traffic across all branch users and applications, including those delivered by XenApp (Citrix's application delivery system).

"With the HDX IntelliCache technology for XenApp, Branch Repeater provides branch staging for streamed virtual applications and branch caching for hosted virtual applications," said the company "And with the new HDX Broadcast technology, Branch Repeater delivers new adaptive orchestration capabilities for XenApp, sensing real-time network and traffic conditions, and dynamically optimising delivery across multiple sessions within the Citrix ICA virtual delivery protocol."

And Citrix claims that Branch Repeater can reduce XenApp traffic by up to 95 percent, "increasing file transfer throughput by up to 20 times and increasing print traffic throughput by up to 33 times." It said that these enhancements allow customers to serve up to four times more XenApp users in each branch "without upgrading bandwidth."

"It looks like this little beastie sits in the branch office and talks to a WanScaler that lives in the main office," said David Cartwright, technical editor of Techworld. "The basic unit optimises the performance of the Citrix sessions your branch office users have open, and the one with the Windows extras has some extra bits in that speeds up the non-Citrix stuff (DNS, DHCP, etc)."

But Cartwright is concerned that it is not immediately clear what they're speeding up. "They claim that this kind of device enables you to chuck away the local server in the branch office ... but the thing is, the Citrix server products (XenServer and whatnot) already do that anyway," he said. "The ICA traffic stream (ICA is the Citrix client-server communications protocol) is extremely efficient, and each user session eats only a few kilobits per second of your WAN - which means that even on a modest WAN link, you can get a good number of simultaneous connections with excellent performance."

He mentioned a former client, who used Citrix on a UK-wide WAN connecting 20 plus sites. "They're more than happy with the performance, even though they don't use the Branch Repeater. Likewise my current client has a global WAN, and they similarly have a central data centre in the head office location and Citrix clients on desktops around the world."

"So unless this does something like prioritising the traffic flows so that Citrix gets guaranteed bandwidth over the rest, I can't really see what it achieves," he said. "And as for DHCP, DNS and whatnot ... big deal. I used to have proxy DNS and DHCP on Bay Networks routers when I was IT bod for CMP, back in the late 90s."

Citrix could not be reached for a response at the time of writing.

Last week, Citrix unveiled the latest version of its XenDesktop platform, saying it was looking to cut the cost of desktop virtualisation and improve the overall user experience.