Splitting our the vlans per dorm as you have suggested increases the configuration and management complexity in a centralized controller environment and can present roaming challenges where dorm users can hear each other.
Bruce Osborne Wireless Network Engineer IT Network Services (434) 592-4229 LIBERTY UNIVERSITY 40 Years of Training Champions for Christ: 1971-2011 ________________________________ From: Holland, Ryan C. [holland....@osu.edu] Sent: Thursday, June 23, 2011 9:08 AM Subject: Re: iOS devices on wireless Bruce is correct in that each residence hall could be placed on its own vlan, thus enabling L2 protocols such as bonjour. I believe Bruce's argument is vlan pooling allows for easier operational administration (e.g., can easily increase capacity by adding to the pool). Both are true statements. It comes down to operational requirements versus customer requirements, and each university will have their own philosophy on how to balance that. ========== Ryan Holland Network Engineer, Wireless Office of the Chief Information Officer The Ohio State University 614-292-9906 holland....@osu.edu<mailto:holland....@osu.edu> On Jun 23, 2011, at 8:32 AM, Osborne, Bruce W wrote: Jeff, Large wireless subnets increase airtime consumed by broadcast traffic. That is why we use a VLan pool of /23 subnets. The clients are distributed automatically based on a hash of the mac address & the number of subnets in the pool, so we cannot easily control which subnet a user gets. Changing the number of subnets in the pool recalculates everybody's subnet too, so we make sure we have plenty of capacity. Bruce Osborne Wireless Network Engineer IT Network Services (434) 592-4229 LIBERTY UNIVERSITY 40 Years of Training Champions for Christ: 1971-2011 -----Original Message----- From: Jeffrey Sessler [mailto:j...@scrippscollege.edu] Sent: Wednesday, June 22, 2011 4:30 PM Subject: Re: iOS devices on wireless Bruce, You could, by any number of technical solutions, ensure that students within a given residential space were all on the same L2 network. That is to say, if a given residence hall is made up of 200 students, then it's not technically difficult to ensure all the residential wireless devices within that area are placed in the same VLAN. Or, at a minimum, to ensure that a user's device(s) will always be in the same L2 network so that they can see each other. If one can't do that, then I wouldn't consider the wireless solution to be very flexible, especially given the trend in devices wanting/needing to talk to each other. On my campus, students spend four years of their life in what we consider a residential setting, and it seems only logical to me that the experience should, to the extent possible, mimic home life. That is, it's reasonable to me to expect a student's wireless devices to see each other, and that they should be able to share/collaborate with the other users within their residential hall. I know that if I was back in college, I'd expect that level of functionality, and If it wasn't there, I'd probably make it happen using my own gear... exactly what you don't want happening. Jeff "Osborne, Bruce W" <bosbo...@liberty.edu<mailto:bosbo...@liberty.edu>> 6/22/2011 4:55 AM >>> We here at Liberty University have about 8000 students in our residences, the vast majority using wireless. That would be a *huge* L2 network. Bruce Osborne Wireless Network Engineer IT Network Services (434) 592-4229 LIBERTY UNIVERSITY 40 Years of Training Champions for Christ: 1971-2011 -----Original Message----- From: Jeffrey Sessler [mailto:j...@scrippscollege.edu] Sent: Tuesday, June 21, 2011 3:05 PM Subject: Re: iOS devices on wireless Mike, I take it you are not able to reference housing data and then place all students/student devices from the same residential hall into the same VLAN? Jeff Michael Dickson <mdick...@nic.umass.edu<mailto:mdick...@nic.umass.edu>> 6/21/2011 11:18 AM >>> On Jun 21, 2011, at 2:04 PM, Jeffrey Sessler wrote: My belief is that a student should be able to have a similar experience when in a residential hall as they would at home. That requires supporting everything under the sun including Bonjour. Unfortunately our enterprise network is sufficiently different enough that the user cannot have a similar experience as they would at home. At home all of their devices are segregated in an L2 network. All their neighbors devices are in their own L2 network, etc. They can browse and discover all the devices in their house but not (hopefully) the devices in their neighbors. Here at UMass their L2 domain is huge and includes mostly unknown devices. Plus, thanks to vlan pooling, it is likely that all of their devices are not in the same L2 subnet. So the "similar to home" experience is not a reality for us. Personally I think students should not think of an enterprise network as similar to their home network. That's a dangerous concept given most students turn on every sharing feature and protocol they can find at home - with relative (L2) protection from the outside world - in an effort to make all of their music and videos work in harmony across all devices. My understanding is that Bonjour only discovers devices at L2, not across L3. If that is correct and our enterprise wireless network offers no less than a dozen L2 networks per SSID in a vlan pool configuration (Aruba), then users aren't discovering their devices in most cases anyway. -Mike ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. -- BEGIN-ANTISPAM-VOTING-LINKS ------------------------------------------------------ Teach CanIt if this mail (ID 1216442291) is spam: Spam: https://antispam.osu.edu/b.php?i=1216442291&m=a41defc3c0c3&c=s Not spam: https://antispam.osu.edu/b.php?i=1216442291&m=a41defc3c0c3&c=n Forget vote: https://antispam.osu.edu/b.php?i=1216442291&m=a41defc3c0c3&c=f ------------------------------------------------------ END-ANTISPAM-VOTING-LINKS ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
