Active Measurements - Hosting a Probe

Introduction

Situational awareness is very important in Internet operations, especially in abnormal situations when the business-as-usual tactics cease to work. Do you remember times when you wanted to know if anyone else was experiencing the problems you were facing? Wouldn't it be nice to have a dependable 'weather map' of your region or even the Internet as a whole?

On a more strategic level there is great interest for comparative data about Internet connectivity on the local, national and regional levels. Currently there is a focus on last-mile broadband speeds, because these are relatively easy to measure and understand. However as the last mile speeds increase, RTT (round trip time) and loss towards the real destinations will become more and more important to watch. To be meaningful, such measurements must be done continuously and not incidentally.

In previous articles I have described the need for more vantage points for active Internet measurements and the prototype of a small probe to achieve that. We have also reported some ad-hoc IPv4/IPv6 measurements using an early version of the probe.

In this article I will describe how we intend to convince you and thousands of others to help these measurements by hosting one of our small probes.

The photographs are of a pre-production unit. The production versions will look a little different and will have a nicer colour.

What You Can Do To Help

We will give a small, USB powered probe to you; it has an RJ-45 connector which speaks 10base-T and 100base-TX Ethernet. The probe is designed exclusively to perform active measurements and not to observe other traffic. Initial measurements will be ICMP/ping, DNS queries and traceroute. We will ask you to connect the probe to your part of the Internet and tell us where it is geographically. "Your part of the Internet" means any network where you have permission to do so; it may be your home broadband connection, your office network or some ISP network in a co-location somewhere.

All the probe needs is a local address via DHCP and/or IPv6 RAs and connectivity to the Internet for ICMP(6), SSH, DNS, HTTP and a few other things. All connections are initiated by the probe. No special configurations are needed for NATs or firewalls; no incoming connections need to be directed to the probe. Once connected, the probe will contact our measurement infrastructure, obtain a list of measurements it needs to perform and pass the results back. Because the probe does not observe any local traffic, it is perfectly OK, and in fact recommended, to install it behind a local switch port to isolate it from other traffic. A home router will do fine as well.  Of course the probe also needs power via its USB connector. That connector is not used to exchange any data; it is just there to obtain power. You can provide this by connecting it to a nearby USB port or you can use one of the ubiquitous USB power supplies.

Obviously the probe will use some of your bandwidth to do the measurements. When registering the probe, you will be able to tell us how much bandwidth you would like to give to the probe; this will typically be a small amount compared to your upstream bandwidth.

So, all we ask you is to contribute a small amount of electricity and a small amount of bandwidth. Now why would you do that? And why would thousands of others do the same and become probe hosts, too?

Motivations

Of course you are an operational networker and you see the benefit of large scale measurements. That alone is enough motivation for you to help us. A little bit of altruism and a belief that the results of the measurements will be useful to you is enough to convince you. And we appreciate that attitude and your help ;-).

However it is unlikely that there are thousands like you so we have to do better. So, we looked at other motivations. Here is our current thinking:

Recognition

Even you may want to be recognised for your altruistic contribution. And maybe you participate as part of a whole group of enthusiastic people who may want to be recognised as a group. We will address that by measuring your individual contribution (and, very likely, that of your group as a whole) in terms of bandwidth and uptime. We will publish various rankings to recognise the contributors. 

Privileges

We will make sure that hosts get privileged access to publications of measurement results. Hosts will also have a privileged way to participate in the development of our measurements.

Results

Hosts will have real-time access to the status of their probes and to a number of measurements taken by the probe. This means that by putting a probe on one of your networks you will get a 24/7 report of the connectivity of this network.

Your Own Measurements From Anywhere!

Now for the 'killer app': by hosting a probe you will be able to specify your own measurements using all other probes in the measurement network. So by hosting just one probe, you can get access to a very large number of vantage points from which to do your own measurements. For instance if you operate a web site and would like to monitor its availability from -say- Germany, you could specify a measurement from 10 probes in Germany every 10 minutes for a week and have hard figures available to you. 

Earning and Using Credits

By now you think this is too good to be true: install just one probe and get unlimited access to all other probes. How is this going to work out if everyone starts measuring all they like? And you are right, this is not going to work. So we have to put the benefit you can get into proportion with your contribution: by hosting a probe you earn credits proportional to the time your probe is operational and to the bandwidth you offer. You can then spend those credits to perform your measurements.

Here is an example with totally arbitrary values: For every hour that your hosted probe is operational and can use 100 kbit/s of upstream bandwidth, you earn 100 points. Running a one-off ping measurement uses up -say- 10 points. Assuming these arbitrary values you could run a ping measurement from 10 vantage points to a single destination every hour in return for hosting the probe. If you want to do more measurements you have to donate more bandwidth, host an additional probe or get other hosts to donate their credits to you.

Here is a rough mock-up of how you will be able to define measurements:

Of course this is a conceptual view. The actual look of the pages may be very different. Since we want probes operated 24/7, we envisage bonuses for every 24h, week and month of continuous operation. We may also give you a sizeable welcome bonus once you have registered your probe, told us about its geographic location and connected it up. There may be other bonuses for answering surveys and the like. I am sure there will be lots of ideas to reward a little effort for the benefit of the community.

Community

Speaking of community: we will support collaboration by sharing credits and results among hosts. You will be able to join with others in order to perform a common set of measurements and share the results. We will also make it easy to publish reports about such results on RIPE Labs and other popular community channels.

Of course the RIPE NCC will also perform measurements on behalf of the RIPE community. We will use aggregated data from all the measurements done by the probes to develop new tools for the benefit of all. I will describe our detailed plans for this in a later article.

Stay tuned for the next article where I will explain how you can earn a serious amount of points and increase your community standing by sponsoring a number of probes.

If you are interested to participate in this measurements network, please contact us at labs at ripe dot net.