Phil Wolff made some interesting remarks concerning "Presence" on Skype Journal and he asked me a question: Note to Jean: how does this affect the number of simultaneous users online?

It is evident that if every Skype user on earth had a permanent Internet connection and an affordable device that he dares to leave "on" 24 hours a day, this would have a dramatic effect on "concurrent users online." See also the review of such a device by Joerg Droege on his Nafcom "Nafcom's Crap Blog" (his wording ;-) : Product Review: Ipevo SOLO.

If we could give these features right now to 50% of the World Wide Skype Users, the 24 hours graph would look like the green curve on the embedded graph. Or if we could provide this to EVERY Skype User, it would somehow look like the red curve. I use here the acceptable guess of Hudson Barton of 30 million "real users" as a maximum. (A "real" Skype user is approximately the same as a user whose presence is detected daily).

Some comments on this graph and the consequences of "permanent Skype connectivity":

• The fluctuations in concurrent users online today (blue curve) are due to people switching off their computers (mainly at night), or using Skype "only when they need it"

• Therefore, providing people with "permanent" devices, would smoothen the fluctuations (some people already leave their computers switched on) and would raise the number of concurrent users online as shown on the green and red curves of my graph

• If this happened "today at once", this would NOT raise "today" the number of "real users"

• A lot of people stick to their mobile phone or PSTN line because they want to be reachable 24 hours per day. Therefore, providing "permanent" or "mobile Wi-Fi" devices, could, in the long run, boost the growth of Skype

• More SkypeIn numbers in more countries would also boost the usage of permanent devices

• And... more people permanently reachable would encourage other people to join the Skype users cloud (this is the contrary of a vicious circle!).

I don’t think that the "permanent" or "mobile" devices will have a huge impact on Skype users in 2008:

• They are still quite expensive (more than cheap mobile phones), and most people join Skype to have cheap communications, not to spend money on nice hardware devices.

• Besides the price of the device, there is another factor that has a negative impact, especially in Europe: due to all the justified hassle about energy consumption, depletion of petrol reserves, global warming, etc. people are reluctant to leave all their electricity consuming devices permanently on. Therefore, only those people who have Skype Devices as a complete replacement of mobile or PSTN phones will dare to leave them 24 hours on!

As posted on Jean Mercier's Skype Numerology blog.