R&D and customer feedback drive upgrades to OverTheBox

What started as a proof of concept for aggregating internet connections in order to provide better bandwidth has become an increasingly essential solution to support cloud usage, which requires high bandwidth, and to bridge the digital divide. So much so that OverTheBox has recently come out with a new version.

"What makes me most proud is that OverTheBox (OTB) is purely the result of our own R&D project, enhanced with customer feedback," says Basheer Essa, R&D telecom engineer at OVH. The initial idea was to find a product that would allow the customer to ensure the reliability of their internet access and increase their bandwidth. After extensive research and testing, the first version of OverTheBox was born. "As time went by, new ideas emerged. Customers gave us a lot of feedback and we took it into account. The vast majority of users found the first version of OTB ‘too complicated’. And on our side, we R&D geeks are always looking for performance gains and additional features, micro adjustments. Combining these two complementary viewpoints, we ended up with the second version of OTB.”

In concrete terms, first of all the new version is three times more powerful than the original version, with a maximum encrypted data rate of 400 Mbit/s compared to about 130 previously. This is thanks to the use of a super-powerful and state-of-the-art SOC, so state-of-the-art in fact that we had to modify our kernel to be able to switch off the box!

Among other new features, a switch has been integrated in the front panel. This is an essential component for simplifying the configuration, as customers no longer need to disable the DHCP in their box to operate the service, which was a major downside of the first version. This switch has 14 ports, including 2 WAN by default, but everything can be easily modified by the customer if desired. The ergonomics of the case has also been upgraded to a "rackable" format. This is aimed at our new professional customers who rely on OTB for their networks.

The hardware aspect is only part of the new version of OTB. The system has also been completely overhauled. However, it remains very complex and development is ongoing to try to simplify it as much as possible.

Adrien Gallouët, OTB developer, lifts the lid on the project for those curious to understand how it all works.

There are two aggregation technologies in OTB V2. Firstly there is MPTCP, based on TCP, which allows only TCP connections to be aggregated. Then there is MUD, based on UDP, which allows all protocols to be aggregated. Each of these technologies has different characteristics. MPTCP tries to maximise bandwidth while maintaining acceptable latency, while MUD tries to minimise latency while trying to maintain acceptable bandwidth.

The first version of OTB ran on a TCP tunnel for non-TCP traffic (which is therefore not aggregated by MPTCP). Aggregation sacrificed latency for bandwidth, which was not always appropriate for traffic, especially VoIP. So we added a new MUD-based tunnel to aggregate latency-sensitive communications (and jitter in particular).

We offer three different aggregation technologies: - a TCP proxy that allows the aggregation of all TCP traffic with MPTCP; - a TCP tunnel that allows aggregation of non-TCP traffic, but is not sensitive to latency and jitter; - a UDP tunnel that allows the aggregation of everything else.

Selection of the aggregation mode is done via the DSCP and is fully configurable by the customer, but we suggest a default configuration that is sufficient for regular uses.

One of the main criticisms expressed by customers via forums or events, and particularly at the OVH Summit 2017, was the complexity of configuration. "The first version needed lots of adjustment and left the user free to configure almost all the parameters," explains Grégoire Delattre, devops on the project from the very beginning. This assumes that the customer knows something about it and has the appropriate skills. Otherwise there is a high risk of failure in achieving the desired quality. That is why we have opted for a default configuration in this second version. It is much easier for the vast majority of users and the results obtained are, on average, much better. People who really do know what they are doing will of course always be able to configure and customise it as they see fit, as Adrien explained.”

"We always want to do better. We already have in mind other potential improvements, such as integrating the vRack private network solution with the OverTheBox service to make OTB a gateway to all OVH services," continues Grégoire. In the meantime, version 2 is living up to its promises, to such an extent that a customer who used to call us as soon as he noticed the slightest drop in bandwidth now never contacts us at all, because his OTB solution automatically solves the problem!”

In terms of offers, three solutions are now available. As the OverTheBox was designed in open source, it is possible to subscribe with just a monthly subscription, without purchasing the box. Simply download the source code of the software and install it on compatible third-party hardware. For those who already have the first version and would like to upgrade to the new one, simply contact support and they will perform the necessary migration. If you are satisfied with the first version and do not necessarily need more stability and power, don’t worry, it will continue to work and stay up to date.