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We will be replacing our campus network in the next year or two, and we are leaning towards increasing the use of wireless since most people primarily work from laptops & mobile devices. Plus, we can even order desktop PCs with wireless cards and still use wired ports where it’s needed. We don’t necessarily need a network port at every desk, and we can order fewer switches.

But wait. Our voice people are looking to go VoIP, which would require a network port for every phone. Even if they could do VoIP over wireless, they still want to use PoE so they don’t have to worry about electrical outlets. So now it seems we’re back to one network port per station.

So, my questions for anyone who has been through a similar upgrade recently:

  • Have you been able to reduce your switch count even though you were using VoIP?
  • Did you still use PoE switches, or did you use a combination of VoIP over wireless and maybe a large scale injector system?
  • Is VoIP over wireless even a good idea (I doubt we’ll do this but was curious)?
  • Is it worth it to seriously beef up your wireless infrastructure if you’re going to need a switch port at most every station anyway?

We have a medium sized campus with both office and lab space. We have around 500 people, 5 buildings and 15 IDFs.

I realize that a VoIP phone at every desk doesn’t make much sense financially, but the company has decided they still want desk phones everywhere.

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While wireless is a good, convenient, possibly necessary thing for a company to have and use, you don't own the airwaves, and you must be willing to accept any interference that disrupts your Wi-Fi, even if it disrupts your business. Having a wired infrastructure can save your business a lot of money. I don't think you really want to bet the company on something that is out of your control. Also, a proper wireless infrastructure (WLCs, WAPs, and supporting hardware) can be as much or more than a switched network infrastructure, and it takes work to keep the wireless network properly tuned.

The problem with VoIP over Wi-Fi is that QoS, necessary for VoIP, is problematic for Wi-Fi. Wired VoIP phones are actually switches, too, so you can connect a PC through a phone, using a single switch interface for both devices. That saves on the number of switch interfaces necessary.

The company where I work has people drooling over the idea of wireless-only sites, but it just has not proved practical.


FYI,

The ANSI/TIA/EIA 568, Commercial Building Telecommunications Cabling Standard actually calls for a minimum of two telecommunications outlets per work area:

Each individual work area shall be serviced with a minimum of two telecommunications outlets. One will be associated with voice and the other data.


Edit for the comments:

If everyone suddenly switches to Wi-Fi for primary network access, you must be prepared for disappointment. The users often have expectations from using Wi-Fi at home that you simply cannot meet in the workplace. For instance, a home user have very little wireless contention on the half-duplex medium, but there will be much more contention in the office. Only one device on a particular Wi-Fi channel can use the medium at any given time, and the Wi-Fi protocol enforces sharing.

A home user downloading files doesn't have much competition for the WAP, but given multiple users on a WAP trying to simultaneously send and receive files, you will notice it, and network drive shares can seem very sluggish. On-line meeting software, like Lync or Skype, can be greatly affected, too.

It's not all bad. Things like limited networking for things like meeting rooms get much easier to remedy. The key is to manage user expectations, but don't expect that you can actually do a good job of that when so many people have such high expectations based on what they experience at home every day. There are companies that have made the transition and enjoy it, but how they use the network may not even resemble how your company uses the network.

You need to be prepared for some users to simply revert to wired networking for most things. The more users that do this, the better the wireless network performs for the remaining wireless users. A natural balance will be struck, but it may take some time as users switch back and forth before settling to what they prefer.

Also, you really need to hire a company to do a wireless site survey before you decide on how to design the wireless network. This will give you the WAP quantities, WAP placement, frequencies to use on each WAP, power levels for each WAP, etc. Shortly after you implement the wireless network and start using it, you should perform a follow-up wireless site survey. This will help you fine-tune things for optimal performance. It is not a bad idea to do this every year or if you notice problems. Things one the airwaves do change. For example, you could have a neighboring company move in and crank up their Wi-Fi radios to full power on a frequency that you are using close to their location.

All in all, between the expanded number of WAPs, the switches required for the WLCs, and the users that prefer to remain on the wired network, you will probably not save many switch ports, if any. You may find that you use more switch ports (switches do come with fixed port quantities).

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    An interesting point to add to this are the sheer number of other devices that are now requiring PoE - from door badge readers to lighting, cameras, thermal/motion sensors, etc. It's also worth noting that there's a push toward higher-output PoE to both charge laptops and power desktop video conferencing equipment (big screens, cameras, etc). The other thing to consider is that the higher density of AP's required to support all users ends up requiring a bunch more ports (albeit in the ceiling). – rnxrx Jan 31 '17 at 1:50
  • And the bandwidth for each switch interface must now be shared among many users, rather than dedicated per user. – Ron Maupin Jan 31 '17 at 3:43
  • Hi Ron, thanks for adding the bullets. I realize that we don't own the airwaves and we do already have a wireless infrastructure and I'm well aware of what WLCs and WAPs cost. At a company of any size, the purchase of a WAP/WLC infrastructure is a given. I also know how VOIP phones work. I am not concerned with the number of jacks at each station as those are already wired. I'm more concerned with the possibility (or not) of switch port reduction. – RSS Jan 31 '17 at 15:38
  • My question centers around peoples' experiences with going to a "WiFi first" type of model especially when they are also using VOIP. With Brocade buying Ruckus and HPE buying Aruba, switch vendors are attempting to better consolidate WiFi into their products. Again, I am looking for people who have been through a similar upgrade to provide insight. – RSS Jan 31 '17 at 15:38
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    How can you claim our experience is wrong? It is what it is. We have spent a fortune to roll out Wi-Fi to thousands of sites, and thousands more to come. I really don't think the blanket Wi-Fi for everyone, everywhere really worked out, and that resources could have been better spent on targeted sites and specific locations in those sites. A relatively few users actually use Wi-Fi as their primary network connection. When a site gets Wi-Fi, everybody is excited and tries it, but disappointment soon sets in. It's a very good thing for conference rooms and people visiting other offices. – Ron Maupin Jan 31 '17 at 23:42
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we’re back to one network port per station

You're back to one network port per wired IP phone and/or wired endpoint. Other endpoints in a typical campus includes IP video cameras, badge readers, and other PoE capable devices.

There is still a place for wired ports because of power delivery. Otherwise, you could get rid of the access switches alltogether.

Idea1 - Preferred

Use single number reach which allows you to publish a campus owned DID(phone number) that will auto matically ring their personal cell, while preserving campus voicemail (vm as an email attachment).

Idea2

For the majority of users, a soft client (downloadable on a tablet or smartphone as an app) on their personal smart phone. So, you still utilize an IP-based PBX but you limit the number of hardphones to fewer users.

Like I said though, PoE is more than just IP phones...

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  • Yes, that was the crux of my question. That POE can throw a monkey wrench into your plans to reduce the number of switch ports. I think there are high density power injectors you can install but you still need to deliver the data and those devices may not be set up for wireless. I'll mention your single reach number idea to the voice people. However I think for lab safety reasons, we still need some wired phones. – RSS Jan 31 '17 at 22:29
  • EMS to the right building = e911 solution or most easily getting PSTN carrier to drop an analog line into each buliding. IP pbx then configired to route 911 out correct POTS line so EMS shows up at correct building. Switch ports are dirt cheap now... PoE is a good thing. All in all though, you should not need more switch ports while serving double, triple, quadrouple more clients (smart phones + tablets). Not everyone will need a campus phone #. Use a web portal or email contacts feature to enable users to id phone numbers. – Ronnie Royston Jan 31 '17 at 23:27
  • Switch ports are dirt cheap? A few years ago when I was at my last job a 48 port C3750-X with the module, maybe a couple of fiber SFPs tax, shipping, etc was almost $10K. At least that's what it was with our "corporate standard" list of options. – RSS Feb 1 '17 at 0:09
  • Fair. That's a fair statement. However, the 2960X is all you really need if you want Cisco. I'm sure they have a new model now that's even faster/cheaper than the 2960X. – Ronnie Royston Feb 1 '17 at 0:13

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