Analysis: Radiance's New CDN App Boosts File Delivery

Radiance announced today it's beefing up the user interface of TrueDelivery, its content-distribution network (CDN), and adding a new application aimed a facilitating gigabyte-sized file transfers between users. Although well-adapted to niche markets, TrueDelivery lacks centralized traffic-control mechanisms and hasn't been integrated with common business applications, making it difficult for most businesses to justify its high price tag.

TrueDelivery is a global CDN that provides rapid data transfer across the Internet to specific users and locations. Various TCP-optimization, compression and caching techniques help realize higher throughput than you'd achieve with standard TCP/IP transactions alone. The product was marketed as a method of transferring very large files-those in the multi-gigabyte range-and as an alternative to physically mailing data on removable media. The revamped UI is designed to make the product more usable to end users on a day-to-day basis. Several different deployment models are offered, including on-site licensed servers, Web-based cached content and a fully managed service.

Radiance has added several convenient features to the TrueDelivery client interface, referred to as Courier. Multiple files can now be sent by dragging and dropping from Windows Explorer to Courier. Recipients are listed in Courier by their e-mail addresses, imported LDAP files, from Active Directory domains or as registered users in the Radiance managed service. Users can track and verify that files were received. Files can be associated with users or groups, and automatically sent to selected individuals or groups when modified. Scheduling options allow for the files to be sent during off-peak hours.

How It Works

TrueDelivery only works with programs that are designed to use its network, so Courier provides a means to access the Radiance CDN. Enhanced APIs and troubleshooting tools are included in this new release. Application developers also can use the TrueDelivery APIs to embed the functionality into custom programs. However, most business applications are not out-of-the-box TrueDelivery-ready. This means users can't employ conventional apps, like Outlook, Notes, Internet Explorer, or existing FTP apps for optimized file transfers. Radiance claims this version is the start of better integration and future versions are expected to integrate with apps, including Outlook. By contrast, a wide area file services (WAFS) or WAN-optimization product sits on the network and works with nearly all applications.Radiance uses multiple IP sessions, several TCP windows and aggressive data-sending techniquest before acknowledgements return to speed up and bypass inefficiencies in TCP. These techniques don't follow the TCP specification-its window sizing and slow-start was designed to minimize network congestion. However, similar techniques have been used for years in competing traffic-optimization products from Expand Networks, Juniper Networks (formerly Peribit) and others. Radiance claims up 30 times faster file transfers in hostile networking environments compared with unmodified TCP/IP alone. On low latency and relatively clean networks, there may be no speed increase at all. However, in environments with many router hops, long physical distances (say, over international links), satellite connections and unreliable networks, the difference shows.

By comparison, in Network Computing's last WAFS review, Juniper Networks's WXC WAN Acceleration Appliance was able to deliver up to a 15x performance increase on real-world data when faced with 4 percent packet loss on a T1. Juniper also claims its product offers 30x acceleration, but that's an optimal figure, not real-world number.

In addition, you don't need to install a hardware device to take advantage of TrueDelivery, as you must do with WAFS. The service knows where the data is going and can intelligently route traffic through the fastest access point. This makes it an ideal acceleration technology for remote, roaming and small-office workers.

NWC Analysis

Overall, we're concerned with the ability of TrueDelivery to prioritize file transfers partly because the product is designed to optimize and saturate a connection. Radiance can deliver improved performance because it overcomes some of the inefficiencies in TCP/IP. By design, TCP will start slow and ramp up using bandwidth. This prevents TCP from monopolizing and congesting the network, but Radiance essentially removes this safeguard. This new version lets a user set priorities on his own file transfers. However, what's missing is the ability to say that user A's high-priority files are more important than user B's high-priority files, or that DNS traffic is more important than both those. WAN optimizers can use QoS (quality of service) techniques to control which priority, but can't act on a file-by-file basis. Radiance considers its solution complementary rather than competitive to WAFS, and is looking into partnerships with WAFS vendors.Radiance also is expensive. Although the price is influenced by network design, number of locations and number of seats, typical price quotes can quickly ramp up. Radiance estimates a deployment supporting a group of eight to 10 collaborative teams, in a managed service model, could cost from $8,000 to $15,000 per month. A Fortune 100-sized company could be looking at around $100,000 per month. These quotes were based on typical deployments, not exact specifications.

Radiance starts pricing for the product at $220 per seat for the first 25 desktop user clients and offers bulk discounts. That's about half the cost of Microsoft Office, or double the cost of a complete desktop-management system, adding just transfer files. Overnight delivery on DVD or tape remains cheaper for occasional transfer needs. However, if you need to transfer large files every day, shipping will cost more than Radiance and require several hours of work.

Another alternative would be upgrading connectivity. Upgrading your Internet connection by a factor of 2x would be cheaper for enterprises using commercial broadband DSL or cable. But poor network connections, such as international and satellite links, won't see as great a speed increase, due to TCP inefficiencies. Organizations with static branch offices may want to consider going with a cheaper WAFS solution, allowing larger e-mail attachments for internal messages, and install job-scheduling software on end user machines or servers for late night transactions. However, vertical markets, such as video production or CAD, will find e-mail insufficient for gigabyte-sized attachments and should consider Radiance more so than organizations with less aggressive file transfer needs.