Hi Patrick,
Here are some of my thoughts for what they’re worth. J Let me know if they help. I am wondering if anyone else who is running a Avaya IP Phones on their network have limited their voice vlan size? I am being told by a telecom vendor that the Avaya phones should reside on a subnet no larger than a /24. Can anyone else confirm or deny this? I managed an enterprise Avaya phone system at Hudson Valley Community College for 4 years, 2008-2012. I believe the recommendation behind smaller subnets is truly best practice going back a ways for broadcast issues in the past. This is still true today as devices have to process every broadcast. I would still try and keep subnet sizes to /24 or as close as you can get to it that makes sense for your network topology. I used /24 and /23 subnets – by: geographical location, building by building, floor by floor, port counts needed for each area. Having a separate VLAN for just VOIP is also recommended by Avaya. We are experiencing jitter on our phones and the CoS configuration on the network side looks fine. Two things here – · Since your routed, are you assigning QoS? CoS operates only on 802.1Q VLAN Ethernet at the data link layer (layer 2), while other QoS mechanisms (such as DiffServ<http://en.wikipedia.org/wiki/DiffServ>, also known as DSCP) operate at the IP network layer (layer 3) · Jitter issues are usually due to either slow or heavily congested links. I would try to find out what link/s may be causing the issue; try and upgrade the bandwidth where necessary. In summary, I think if you have CoS and QoS configured properly; you address the congested link/s, you’ll solve the problem. Thanks, *Rob Kwiatkowski* Solutions Engineer, Upstate and Western NY Enterasys Networks Cell: 518.378-5177 Email: [email protected] *”There is nothing more important than our customers.”* *From:* Patrick Printz [mailto:[email protected]] *Sent:* Tuesday, October 08, 2013 6:43 AM *To:* Enterasys Customer Mailing List *Subject:* RE: [enterasys] Avaya IP phone subnet size No routing at the edge currently. The phones Mac auth and get the proper role, which assigns the vlan and CoS. *Patrick Printz* *Network Infrastructure* Quinsigamond Community College 670 West Boylston Street Worcester, MA 01606-2092 w. 508-854-7517 c. 508-726-9529 When technology fails you, just call the help desk. (x4427/[email protected] ) "If a man is called a street sweeper, he should sweep streets even as Michelangelo painted, or Beethoven composed music, or Shakespeare wrote poetry. He should sweep streets so well that all the hosts of heaven and Earth will pause to say, Here lived a great street sweeper who did his job well." ~Martin Luther King, Jr. *From:* John Kaftan [mailto:[email protected]] *Sent:* Monday, October 07, 2013 10:19 PM *To:* Enterasys Customer Mailing List *Subject:* Re: [enterasys] Avaya IP phone subnet size We just deployed an Avaya IP office system too. I cannot confirm or deny whether it is necessary but we went with a seperate vlan per building for voip. For us this means way less than a /24 per building. Although that is how we setup our subnets. We have NAC and we assign a Phones policy with a cos of 6 I believe. No problems. Are you routing at the edge? How so you assign Cos? John On Oct 7, 2013 9:53 PM, "Patrick Printz" <[email protected]> wrote: I am wondering if anyone else who is running a Avaya IP Phones on their network have limited their voice vlan size? We are experiencing jitter on our phones and the CoS configuration on the network side looks fine. I am being told by a telecom vendor that the Avaya phones should reside on a subnet no larger than a /24. Can anyone else confirm or deny this? *Patrick Printz* *Network Infrastructure* Quinsigamond Community College 670 West Boylston Street Worcester, MA 01606-2092 w. 508-854-7517 c. 508-726-9529 When technology fails you, just call the help desk. (x4427/[email protected] ) "If a man is called a street sweeper, he should sweep streets even as Michelangelo painted, or Beethoven composed music, or Shakespeare wrote poetry. He should sweep streets so well that all the hosts of heaven and Earth will pause to say, Here lived a great street sweeper who did his job well." ~Martin Luther King, Jr. - --To unsubscribe from enterasys, send email to [email protected] with the body: unsubscribe enterasys [email protected] - --To unsubscribe from enterasys, send email to [email protected] with the body: unsubscribe enterasys [email protected] - --To unsubscribe from enterasys, send email to [email protected] with the body: unsubscribe enterasys [email protected] --- To unsubscribe from enterasys, send email to [email protected] with the body: unsubscribe enterasys [email protected]
