Re: [WIRELESS-LAN] Aruba's SCA vs. MCA whitepaper [was: Open Wireless in Higher Ed]
Hi Philippe, We'd be very interested, as others are I'm sure to hear what you find out from your testing. -- Don Wright Brown University CIS - NTG On 4/1/08 10:53 AM, Philippe Hanset [EMAIL PROTECTED] wrote: Dave, At Univ of TN, our intention is to deploy 802.11n capable APs where our 802.11b/g AP are located right now, use one radio at 2.4 GHz (b/g only, no n) the second radio at 5 GHz (n and a). This should provide a decent access for b/g users and a fast lane for n users. I'm not sure that best effort on b/g will be good enough when you consider devices like Iphones or future Voice over WiFi devices. One aspect of this kind of approach will be the performance of coverage algorithms. n has such a wierd shape compared to b/g or a...I'm a little suspicious as how vendors will deal with n's behavior! As a side note: We are testing in our info-commons (the worse enviroment you can think of...tons of users and tons of APs) 802.11n APs from Aruba and Meru (we have just replaced locations of our existing Proxim APs with the test APs, and those n APs are surrounded by legacy Proxim APs as well) One week with Aruba, one week with Meru. We might test Cisco...TBD. Our main issue is to get enough people with 802.11n adapters, so we loaded our loaners laptop (30+...very successfull program BTW) with external 802.11n adapters (USB 2.0, Linksys). Philippe Although the issue of co-channel interference is an important one, I think it may be reasonable to assert that its importance will be reduced with the adoption of 5 GHz 802.11n. With over 20 non-overlapping channels, I believe it will be possible to design high-density, micro-cellular WLANs that do not suffer from performance degradation as a resulting of co-channel interference. Over time, I believe 2.4 GHz will be thought of as a best-effort legacy technology for most enterprises. I'd be curious how others are viewing this. dm -Original Message- From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:[EMAIL PROTECTED] On Behalf Of Charles Spurgeon Sent: Monday, March 31, 2008 4:31 PM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: Re: [WIRELESS-LAN] Aruba's SCA vs. MCA whitepaper [was: Open Wireless in Higher Ed] On Wed, Mar 26, 2008 at 10:31:50PM -0500, Frank Bulk - iNAME wrote: I wish it was easier to evaluate the performance (not only aggregrate throughput, but also QoS) of the MCA and SCA products in various scenarios and density and usage, but unfortunately examining the impact of co-channel interference on a large scale in variety of building types and architectures with lots of APs and clients with realistic traffic patterns (in terms of type and longitudinally over time) is not currently possible with the tools available. I think we would learn that there certain scenarios where one performs generally better over another. I, for one, would like to see more vendors step up and do the kind of testing of co-channel interference issues that was described in the recent Novarum whitepaper: http://www.novarum.com/documents/WLANScaleTesting.pdf As a user of typical multi-channel equipment, I'm not focussed on the SCA versus MCA debate. Instead, I would very much like to see more real-world test results on how the typical multiple APs on multiple channels (MCA) approach works at scale and under traffic loads. I think it's very interesting that the author of the Novarum whitepaper is also one of the developers of the 802.11 MAC, and that he states that he was surprised at how easily we could drive these systems to unstable behavior. I've heard complaints from the vendors whose gear was used in the Novarum test. But I haven't seen any third-party tests commissioned by those vendors to replicate the tests and show where the problems were in the Novarum tests. I would be much more impressed by actual third-party test results based on a significant scale layout like the one used in the Novarum tests, rather than hearing complaints about the how the test was unfair since it was done under the auspices of Meru. The problems of co-channel interference and wireless channel meltdown under load are too important to be left to the marketing departments of the wireless vendors. On our campus the community has been adopting wireless networking at extremely high rates, and this technology has become much too important to allow it to be supported this poorly. Isn't it long past time for more real-world scale testing like the Novarum tests to be done to investigate the issues with CCI and channel meltdown under load in 802.11b/g systems and to develop some approaches for identifying and dealing with those issues? -Charles Charles E. Spurgeon / UTnet UT Austin ITS / Networking [EMAIL PROTECTED] / 512.475.9265 ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can
Re: [WIRELESS-LAN] Aruba's SCA vs. MCA whitepaper [was: Open Wireless in Higher Ed]
On Tue, Apr 01, 2008 at 08:25:06AM -0400, Dave Molta wrote: I agree with Chuck about the need for better information about WLAN scalability. It's an issue I've struggled with for many years but I'm not optimistic about a resolution. I've discussed this issue extensively with Phil Belanger, the author of the Novarum report, and I just can't see any way to get all the vendors to agree to a single test plan and commit the resources necessary for such ambitious tests. Although it's clear that Meru designed these tests to best reflect their competitive advantage, I also believe Phil played the role of objective analyst, which is not always the case with pay for test projects. Phil pressured Meru to include test runs that were not part of their original plan and he was very transparent in disclosing his role in these tests. Still, it's highly likely that the results would have been different if Cisco and Aruba had been directly involved. Personally, I still think Meru would have performed better, but I don't think the differences would have been as great. Although the issue of co-channel interference is an important one, I think it may be reasonable to assert that its importance will be reduced with the adoption of 5 GHz 802.11n. With over 20 non-overlapping channels, I believe it will be possible to design high-density, micro-cellular WLANs that do not suffer from performance degradation as a resulting of co-channel interference. Over time, I believe 2.4 GHz will be thought of as a best-effort legacy technology for most enterprises. I'd be curious how others are viewing this. Dave, I agree with you in principle about the need to move to 5 GHz -- but we have an installed base of thousands of APs (and tens of thousands of clients) on our campus that are running 802.11b/g, and I find the vendor refusal to test scale and load issues on 802.11b/g systems to be indefensible. The wireless system on our campus has become critically important to the organization. When do the wireless vendors plan to step up to the task and provide real-world large scale testing and useful guidance on these important issues? As the author of a book on the orginal cabled Ethernet system, I can remember the days when Ethernet was being tested for scale and load. In the early days of Ethernet the scale tests were difficult to arrange, since large groups of high performance computers sharing a network were not as common. These tests resulted in a better understanding of Ethernet behavior and limits, and provided network managers with useful information on how best to configure and deploy Ethernet systems. If the wireless vendors persist in refusing to provide scale testing and persist in refusing to provide the testing results and technical information needed to better understand and operate complex 2.4 GHz wireless systems, then what can we expect when we move to 5 GHz? There is some level of co-channel interference even in non-overlapping 5 GHz channels. Given the levels of performance collapse that were reported in the Novarum paper, and given the insight documented in that paper that the interference range is greater than the communication range of 802.11 products isn't it reasonable to ask that these issues be further investigated? To your point on moving to 5 GHz: we've been working on wireless upgrade plans, including an emphasis on new 5 GHz designs for the usual reasons: increased channel capacity and less interference from non-802.11 sources. Also, we're very interested in seeing what 802.11n can deliver. Like everyone else, we need the new capacity to deal with the massive increases in wireless usage. Some issues that we're encountering include client behavior when it comes to choosing which channel to connect to on an AP that is providing both 802.11b/g and 802.11a/n channels, and client support for the set of 5 GHz channels. While there are 20 (or more) channels defined in the 5 GHz spectrum, the client support for those channels is not what you might expect. I've been digging into the client channel support issue, including some client testing, and will be posting more info as soon as I can get it into shape. Thanks, -Charles Charles E. Spurgeon / UTnet UT Austin ITS / Networking [EMAIL PROTECTED] / 512.475.9265 ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
RE: [WIRELESS-LAN] Aruba's SCA vs. MCA whitepaper [was: Open Wireless in Higher Ed]
Warning Warning - don't touch the N AP's - they can poke you much like a porcupine. Do people really want tarantulas stuck to the ceiling everywhere? A little design humor... Seriously though: Philippe of Univ. of TN wrote Side note again: One thing is sure, Controller Based Architectures are really good at hooking you up then nickeling and diming you to death! A great statement - can you image if today - when you purchased an upgrade of your edge Ethernet switches - if you had to buy a mother-ship of a controller to centrally manage, control, and monitor them? Of course not - that architecture was well over a decade ago in the wired world - and has been solved by centrally managing and monitoring highly intelligent edge devices over our friend SNMP and an NMS. Chad Frisby 303.406.3222 -Original Message- From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:[EMAIL PROTECTED] On Behalf Of Philippe Hanset Sent: Tuesday, April 01, 2008 10:41 AM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: Re: [WIRELESS-LAN] Aruba's SCA vs. MCA whitepaper [was: Open Wireless in Higher Ed] Somehow I was expecting this ;-) If time permits, we will try to really formalize it... Our intention is really to measure if there is a noticeable difference between Meru and Aruba (and maybe between Cisco and Aruba). Since we already acquired Aruba Controllers for our Dorms, we are hooked, only a true advantage from another vendor would make us switch! I can already tell you that we never exceed 80 Mbps download on either one of them (Aruba or Meru), using TTCP (memory to memory) on a Macbook Pro (Linksys adapters are slower) and that uploads are more around 30 Mbps or less. (APs are connected to Gig ports, using Gig capable midspan and regular 802.3af power, the TTCP receiving unit is non-limiting) BTW: have you seen the size of those Meru and Cisco APs...I'm not sure where to fit that in our drop ceilings, seriously! Side note again: One thing is sure, Controller Based Architectures are really good at hooking you up then nickeling and diming you to death! (AP license, IDS license, Firewall license, number of admin on system license, buy licenses for the redundant units as well...) I wonder what experience people have with Monitored Architectures like Colubris or what Proxim is developing these days? Philippe Univ. of TN On Tue, 1 Apr 2008, Don Wright wrote: Hi Philippe, We'd be very interested, as others are I'm sure to hear what you find out from your testing. -- Don Wright Brown University CIS - NTG On 4/1/08 10:53 AM, Philippe Hanset [EMAIL PROTECTED] wrote: Dave, At Univ of TN, our intention is to deploy 802.11n capable APs where our 802.11b/g AP are located right now, use one radio at 2.4 GHz (b/g only, no n) the second radio at 5 GHz (n and a). This should provide a decent access for b/g users and a fast lane for n users. I'm not sure that best effort on b/g will be good enough when you consider devices like Iphones or future Voice over WiFi devices. One aspect of this kind of approach will be the performance of coverage algorithms. n has such a wierd shape compared to b/g or a...I'm a little suspicious as how vendors will deal with n's behavior! As a side note: We are testing in our info-commons (the worse enviroment you can think of...tons of users and tons of APs) 802.11n APs from Aruba and Meru (we have just replaced locations of our existing Proxim APs with the test APs, and those n APs are surrounded by legacy Proxim APs as well) One week with Aruba, one week with Meru. We might test Cisco...TBD. Our main issue is to get enough people with 802.11n adapters, so we loaded our loaners laptop (30+...very successfull program BTW) with external 802.11n adapters (USB 2.0, Linksys). Philippe Although the issue of co-channel interference is an important one, I think it may be reasonable to assert that its importance will be reduced with the adoption of 5 GHz 802.11n. With over 20 non-overlapping channels, I believe it will be possible to design high-density, micro-cellular WLANs that do not suffer from performance degradation as a resulting of co-channel interference. Over time, I believe 2.4 GHz will be thought of as a best-effort legacy technology for most enterprises. I'd be curious how others are viewing this. dm -Original Message- From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:[EMAIL PROTECTED] On Behalf Of Charles Spurgeon Sent: Monday, March 31, 2008 4:31 PM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: Re: [WIRELESS-LAN] Aruba's SCA vs. MCA whitepaper [was: Open Wireless in Higher Ed] On Wed, Mar 26, 2008 at 10:31:50PM -0500, Frank Bulk - iNAME wrote: I wish it was easier to evaluate the performance (not only aggregrate throughput, but also QoS) of the MCA and SCA products in various scenarios and density and usage
RE: [WIRELESS-LAN] Aruba's SCA vs. MCA whitepaper [was: Open Wireless in Higher Ed]
As a grey-haired veteran of early Ethernet, I always try to keep those comparisons in mind. And for those of you who may be newer to networking, you should be aware that Chuck was the go-to guy for technical information in the early days of Ethernet. Thanks for the early education, my friend. Your points about current and future 802.11 implementations are insightful and I agree that we should all be pushing the vendors for more information about performance while also pushing them on functionality, reliability, and cost. At the same time, we need to be careful in testing the outer boundaries of network performance. While I respect Phil Belanger's work, it is really hard with wireless to know if you are measuring the right system attributes and as has been pointed out, the unique elements of the physical medium make things different in different physical locations. In the end, I think the best tests are the real-world tests that take place at .edu's every day. That's what makes these mailing lists so valuable. I've thought about different ways to accomplish these scale tests, talked to folks like Frank Bulk, Phil Belanger and Craig Mathias. Perhaps if an organization like Educause got involved, they could exert enough pressure to get the vendors to participate. But I doubt that would be in the best interest of Educause or the vendors. My own opinion is that all these systems have breaking points, it's just a matter of finding them and then deciding whether they really matter for your application use case. In the mean time, all you guys get to live with the ambiguity of supporting very large networks while I get to spend time in the classroom teaching my students how to dissect whitepapers and identify vendor misrepresentations. dm -Original Message- From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:[EMAIL PROTECTED] On Behalf Of Charles Spurgeon Sent: Tuesday, April 01, 2008 12:00 PM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: Re: [WIRELESS-LAN] Aruba's SCA vs. MCA whitepaper [was: Open Wireless in Higher Ed] On Tue, Apr 01, 2008 at 08:25:06AM -0400, Dave Molta wrote: I agree with Chuck about the need for better information about WLAN scalability. It's an issue I've struggled with for many years but I'm not optimistic about a resolution. I've discussed this issue extensively with Phil Belanger, the author of the Novarum report, and I just can't see any way to get all the vendors to agree to a single test plan and commit the resources necessary for such ambitious tests. Although it's clear that Meru designed these tests to best reflect their competitive advantage, I also believe Phil played the role of objective analyst, which is not always the case with pay for test projects. Phil pressured Meru to include test runs that were not part of their original plan and he was very transparent in disclosing his role in these tests. Still, it's highly likely that the results would have been different if Cisco and Aruba had been directly involved. Personally, I still think Meru would have performed better, but I don't think the differences would have been as great. Although the issue of co-channel interference is an important one, I think it may be reasonable to assert that its importance will be reduced with the adoption of 5 GHz 802.11n. With over 20 non-overlapping channels, I believe it will be possible to design high-density, micro-cellular WLANs that do not suffer from performance degradation as a resulting of co-channel interference. Over time, I believe 2.4 GHz will be thought of as a best-effort legacy technology for most enterprises. I'd be curious how others are viewing this. Dave, I agree with you in principle about the need to move to 5 GHz -- but we have an installed base of thousands of APs (and tens of thousands of clients) on our campus that are running 802.11b/g, and I find the vendor refusal to test scale and load issues on 802.11b/g systems to be indefensible. The wireless system on our campus has become critically important to the organization. When do the wireless vendors plan to step up to the task and provide real-world large scale testing and useful guidance on these important issues? As the author of a book on the orginal cabled Ethernet system, I can remember the days when Ethernet was being tested for scale and load. In the early days of Ethernet the scale tests were difficult to arrange, since large groups of high performance computers sharing a network were not as common. These tests resulted in a better understanding of Ethernet behavior and limits, and provided network managers with useful information on how best to configure and deploy Ethernet systems. If the wireless vendors persist in refusing to provide scale testing and persist in refusing to provide the testing results and technical information needed to better understand and operate complex 2.4 GHz wireless systems, then what can we expect when we move
RE: [WIRELESS-LAN] Aruba's SCA vs. MCA whitepaper [was: Open Wireless in Higher Ed]
Thanks Daniel, All Meru says is put your faith in Air Traffic Control without offering any explanation how it how it addresses (coordinates) the MAC and PHY challenges pointed out in the Aruba article. The spirit of 802.11 is not the necessarily the content of the protocol, but the fact that its out in the open and available for all to understand. The standard itself is mostly based on the interaction between a single client and a single AP. There's no IEEE standard on split-MAC architectures, though LWAPP has emerged as the de facto standard. In lieu of standards, the vendors bear the responsibility of full feature disclosure. To Cisco's credit, they describe the division of hardware responsibility between AP and controller in their split-MAC architecture (standard 802.11 data and management functions terminate at the AP). This, and their Auto-RF mechanisms, are available in their documentation and presentations. That's the spirit that vendors need to honor to keep the faith of their customers. Bruce Johnson Network Engineer Partners Healthcare 617-726-9662 mailto: [EMAIL PROTECTED] From: The EDUCAUSE Wireless Issues Constituent Group Listserv on behalf of Daniel Eklund Sent: Tue 4/1/2008 8:54 AM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: Re: [WIRELESS-LAN] Aruba's SCA vs. MCA whitepaper [was: Open Wireless in Higher Ed] The folks at Meru sent me this link to their response to the Aruba paper. http://www.merunetworks.com/technology/aruba_response_033108.pdf -- Daniel Eklund Director, Network Engineering Wayne State University Detroit, MI 48201 Phone: 313-577-5558 Fax: 313-577-5577 ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. The information transmitted in this electronic communication is intended only for the person or entity to whom it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of or taking of any action in reliance upon this information by persons or entities other than the intended recipient is prohibited. If you received this information in error, please contact the Compliance HelpLine at 800-856-1983 and properly dispose of this information. ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
Re: [WIRELESS-LAN] Aruba's SCA vs. MCA whitepaper [was: Open Wireless in Higher Ed]
On Wed, Mar 26, 2008 at 10:31:50PM -0500, Frank Bulk - iNAME wrote: I wish it was easier to evaluate the performance (not only aggregrate throughput, but also QoS) of the MCA and SCA products in various scenarios and density and usage, but unfortunately examining the impact of co-channel interference on a large scale in variety of building types and architectures with lots of APs and clients with realistic traffic patterns (in terms of type and longitudinally over time) is not currently possible with the tools available. I think we would learn that there certain scenarios where one performs generally better over another. I, for one, would like to see more vendors step up and do the kind of testing of co-channel interference issues that was described in the recent Novarum whitepaper: http://www.novarum.com/documents/WLANScaleTesting.pdf As a user of typical multi-channel equipment, I'm not focussed on the SCA versus MCA debate. Instead, I would very much like to see more real-world test results on how the typical multiple APs on multiple channels (MCA) approach works at scale and under traffic loads. I think it's very interesting that the author of the Novarum whitepaper is also one of the developers of the 802.11 MAC, and that he states that he was surprised at how easily we could drive these systems to unstable behavior. I've heard complaints from the vendors whose gear was used in the Novarum test. But I haven't seen any third-party tests commissioned by those vendors to replicate the tests and show where the problems were in the Novarum tests. I would be much more impressed by actual third-party test results based on a significant scale layout like the one used in the Novarum tests, rather than hearing complaints about the how the test was unfair since it was done under the auspices of Meru. The problems of co-channel interference and wireless channel meltdown under load are too important to be left to the marketing departments of the wireless vendors. On our campus the community has been adopting wireless networking at extremely high rates, and this technology has become much too important to allow it to be supported this poorly. Isn't it long past time for more real-world scale testing like the Novarum tests to be done to investigate the issues with CCI and channel meltdown under load in 802.11b/g systems and to develop some approaches for identifying and dealing with those issues? -Charles Charles E. Spurgeon / UTnet UT Austin ITS / Networking [EMAIL PROTECTED] / 512.475.9265 ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
RE: [WIRELESS-LAN] Aruba's SCA vs. MCA whitepaper [was: Open Wireless in Higher Ed]
Yet another architecture (sectorized multi-AP array). This is comparing apples and oranges (except we don't know the variety of traditional apple Tolly is comparing Xirrus to in the study). I think the problem is all these vendors live in Silicon Valley flatland and don't consider the effect of high density in three dimensions. The Novarum test appeared to be an out-of-the-box comparison (no tweaks). I think it would be relatively straightforward for a 3-story building to be surveyed and tested with each vendors architecture and have an independent performance analysis conducted after its been tuned to each vendors satisfaction. But who's going to pay for it? In the tests you see conducted by the industry trade magazines, one or several of the vendors always decline to participate (not confidence-inspiring). Pay attention to who doesn't. Its an issue unique to wireless since it's the only medium that feeds upon itself, and is context (implementer, building) dependent. What we need to know are the assumed parameters for deployment of each vendor's architectures. If the all defaults (all proprietary automated features) bet is off, then we deserve to know exactly what each vendor is doing behind the scenes, especially those that do not follow the spirit of the standards (SCA). If they tell you it depends, then you need to know everything the product does, and get recommendations for how to support all measure of services (voice, video, data, location) and the hazards each have on the other. -Original Message- From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:[EMAIL PROTECTED] On Behalf Of Chad Frisby Sent: Monday, March 31, 2008 4:41 PM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: Re: [WIRELESS-LAN] Aruba's SCA vs. MCA whitepaper [was: Open Wireless in Higher Ed] Wireless Density of users and co-channel interference has already been solved. Micro cell or channel blanket architectures do not. Independent 3rd party test-results below by Tolly Group. http://www.tolly.com/DocDetail.aspx?DocNumber=206152 http://www.tolly.com/DocDetail.aspx?DocNumber=207181 Chad Frisby 303.406.3222 -Original Message- From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:[EMAIL PROTECTED] On Behalf Of Charles Spurgeon Sent: Monday, March 31, 2008 2:31 PM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: Re: [WIRELESS-LAN] Aruba's SCA vs. MCA whitepaper [was: Open Wireless in Higher Ed] On Wed, Mar 26, 2008 at 10:31:50PM -0500, Frank Bulk - iNAME wrote: I wish it was easier to evaluate the performance (not only aggregrate throughput, but also QoS) of the MCA and SCA products in various scenarios and density and usage, but unfortunately examining the impact of co-channel interference on a large scale in variety of building types and architectures with lots of APs and clients with realistic traffic patterns (in terms of type and longitudinally over time) is not currently possible with the tools available. I think we would learn that there certain scenarios where one performs generally better over another. I, for one, would like to see more vendors step up and do the kind of testing of co-channel interference issues that was described in the recent Novarum whitepaper: http://www.novarum.com/documents/WLANScaleTesting.pdf As a user of typical multi-channel equipment, I'm not focussed on the SCA versus MCA debate. Instead, I would very much like to see more real-world test results on how the typical multiple APs on multiple channels (MCA) approach works at scale and under traffic loads. I think it's very interesting that the author of the Novarum whitepaper is also one of the developers of the 802.11 MAC, and that he states that he was surprised at how easily we could drive these systems to unstable behavior. I've heard complaints from the vendors whose gear was used in the Novarum test. But I haven't seen any third-party tests commissioned by those vendors to replicate the tests and show where the problems were in the Novarum tests. I would be much more impressed by actual third-party test results based on a significant scale layout like the one used in the Novarum tests, rather than hearing complaints about the how the test was unfair since it was done under the auspices of Meru. The problems of co-channel interference and wireless channel meltdown under load are too important to be left to the marketing departments of the wireless vendors. On our campus the community has been adopting wireless networking at extremely high rates, and this technology has become much too important to allow it to be supported this poorly. Isn't it long past time for more real-world scale testing like the Novarum tests to be done to investigate the issues with CCI and channel meltdown under load in 802.11b/g systems and to develop some approaches for identifying and dealing with those issues? -Charles Charles E. Spurgeon / UTnet UT Austin ITS / Networking [EMAIL
