Whilst each of the three virtual worlds investigated by the project team had technical requirements, Second Life® was by far the most technically demanding.
So why did the project team choose Second Life? Because members believed it was the only one of the three that offered a wide range of educational opportunities. The other two virtual worlds were designed for specific purposes – Second Life allowed the team to manipulate and use it in very real and dynamic ways.
The IT department at GippsTAFE contributed to this report as a guide to all teachers and their IT departments considering using Second Life.
Computer hardware assessment
The requirements as listed by the Second Life website (viewed 25 September 2006, <http://secondlife.com/corporate/sysreqs.php>) are as follows.
Internet connection: cable or DSL
Operating system: Windows XP (Service Pack 2) or Windows 2000 (Service Pack 4)
Computer processor: 800 MHz Pentium III or Athlon or better
Computer memory: 256 Mb or better
Video/graphics card**: nVidia GeForce 2, GeForce4 mx or better or ATI Radeon 8500, 9250 or better
System recommendations
Internet connection: cable or DSLComputer processor: 1.6 GHz Pentium 4 or Athlon 2000+ or better
Computer memory: 512 Mb or better
Video/graphics card**: nVidia GeForce FX 5600, GeForce 6600 or better or ATI Radeon 9600, X600 or better
The performance of Second Life on the GippsTAFE computers was quite degraded due to the high computer requirements. Areas with large quantities of graphical imagery within the world could cause the system to slow down and reduce its ability to render the Second Life content. This caused delays between drawn frames, resulting in a less pleasurable experience for the user.
Due to the high requirements of the application, students working from home will be likely to have problems with Second Life, unless they have a recently purchased, mid-range computer that has an upgraded video card. The Second Life website also states that a home modem connection is not sufficient. Also, students need to take into consideration their Internet plan when using Second Life at home. The average download for areas not visited previously is roughly 70 Mb over 15 minutes. If a student is on a 500 Mb per month plan, that could easily be used up in a few hours of constantly viewing new areas. Second Life also supports streaming music and video – which would also contribute to total downloads.
Internet bandwidth assessment
Second Life can operate across a range of 50 kbps to 1 Mbps – depending on the traffic flow to the servers of Second Life. If an area is overpopulated with internal connections, the network performance can become degraded and produce ‘laggy’ responses from the server. Second Life can be configured to limit the bandwidth download rate. But this can be modified by the person logged on at any time, meaning that Second Life bandwidth options were not enforceable by GippsTAFE system administrators.
The greatest issue with Second Life on the GippsTAFE network in regards to bandwidth was that, if incorrectly configured, it could potentially take Internet bandwidth from other applications required on the network. This included external web services critical for GippsTAFE’s function.
To deal with this issue, GippsTAFE’s firewall was configured to restrict the speed of download so that Second Life did not potentially starve other applications of Internet bandwidth. There were several issues with this. When the policy was enforced, it had to be modified as it caused problems with the Second Life software. While running Second Life, users would experience frequent disconnections.
GippsTAFE had an 8 Mbps link to the Internet. Second Life could use 1 Mbps per client. If five to eight clients were running at the same time, it meant the Internet link could potentially become saturated and other Internet traffic could become starved of bandwidth. It was imperative that the link not become saturated with traffic to avoid other services becoming unavailable or running slowly. At the time of writing, a long-term solution on this issue had not been found.
Security aspect of Second Life
Second Life is a constantly developed software application that requires updating at least once every several weeks. Such a fast development cycle can introduce ‘bugs’ and security risks that would not normally be encountered. It also puts high maintenance loads on the systems that are required to run the software. Every time a new client is available, student machines that require the update need to have the software installed.
GippsTAFE’s allowing access to Second Life during the period required a range of ports to be open live to the Internet. For GippsTAFE, the issue with this was that an intelligent computer user could use this information and breach all monitoring tools and scanning that the institute uses to protect its network. Possible long-term solutions to this problem were still under consideration at the time of writing.
Australian Flexible Learning Framework