IP Office and VLAN's 3

[PotNoodleBoy]

Hi,

We're about to implement an IP500 with a mixture of digital and IP phones. There's going to be quite a few IP phones and we want to implement VLAN's properly instead of just sticking all the phones on the same subnet!

Does anyone have a simple guide to doing this?

Here's my ideas so far:

Have 2 DHCP scopes on a Windows 2003 server. One for phones and one for data. There will be a 176 option in both scopes to allow phones to release their data address and reboot into the voice vlan.

I need to make each port of the switch(es) a tagged member of the voice vlan and an untagged member of the data vlan?

What about the port the server is plugged in to?

What about the port the IP Office is plugged in to? The IPO willneed to talk to both vlans as I'll be running phone manager on the PC's. Do I need to configure the IPO with 2 addresses?

I'm only planning to plug the IPO and the DHCP server in to the network once, I.E. not with two network cards.

Any other words of wisdom??

 

[PlatinumGuy]

If you are using PM make sure the IPO is on the data VLAN and it has QOS enabled throughout.

The reason for this is BLF updates for PM. They are not voip packets, they are broadcasts and connot be routed across, thus if the IPO is on the voice vlan the broadcasts will not propagate on to the data vlan which the pc's housing the PM will be sat.

ACA - IP Office Implement
ACS - IP Office Implement
ACE - IP Office Implement
ACI - IP Office Implement

 

[dphoneguy24]

I have a question for you then if you say the IPO needs to be on the data VLAN.
The VoIP traffic that has to pass through the IPO (digital phone to IP extension call or IP extension call to analog/digital trunk) will need to use a VCM for the length of the call.
Since the IPO needs this traffic untagged, I suppose you need to make sure you have the proper QoS setup on the switch port that the IPO is connecting to.

It would be nice if they would setup the IPO to allow you to tag any VoIP packets out of the box to the VLAN setup for voice and have all other data either tagged or left untagged to it's appropriate VLAN.

dphoneguy24

 

[intrigrant]

The DHCP Server needs two network interface cards, on for the DATA VLAN and one for the VoIP VLAN.

There must be some kind of routing between DATA VLAN and VoIP VLAN ( Router, DHCP Server, switches or whatever can route packets between the VLANs )
If you have a IP 500 then put LAN2 on the DATA VLAN and LAN1 in the VoIP VLAN, the router can be omitted then.

Qos is only necessery on slow WAN links, it is not a issue on a 100Mb switched LAN as a single Voip call consumes 90kb at most ( G711 codec ).

There are a number of ways to send the tftp files to the phones with the use of a tftp server, read the manuals for that.

NIHIL NOVI SUB SOLE

 

[jamie77]

Is VLANS better than using decent switches with Diff Serv setup??? I've never setup or used VLANS.

Jamie Green

ACA:Implement - IP Office
ACS:Implement - IP Office

http://www.alliedcom.co.uk

Fooball is not a matter of life and death-It is far more important!!!!

 

[kwing112000]

I have heard that VLANS are good because it seperates the voice traffic from the Data. i am not sure it is better but i think it helps. Especially if you have alot of broadcasts on the network. The broadcast will not cross the VLAN.

 

[big70]

You only need one networkcard on the DHCP-Server and be sure the port has no Voice V-lan.

Make sure that you put DHCP-Helpers on the V-Lan,s so the DHCP requests can find the DHCP-Server...

I always put the port of the IPO on a port only in the voice V-lan and untagged.

The IPO uses Diffserf to do Qos and be sure to set the wright values for the network you use...


Greets Peter

 

[PotNoodleBoy]

Thanks for all the input. From my reading around the subject, I know that the DHCP server only needs to be plugged in the network once. As somebody pointed out I need DHCP helper commands on the switches to intercept DHCP requests and pass them to the server on the data vlan.

I'm a little less sure about the IPO itself. As it's an IP500 I might just plug in to the network twice and give it an IP on both VLAN's as suggested.

It's interesting that people aren't bothered about QoS on the local LAN. We've always been over cautious and put DiffServ capable switches in. Is it generally accepted that you won't have problems on a good 100Mbps switched LAN - even with say 75 IP phones & PC's?

 

[as1981]

Rob,

Although not in the number your talking about I have run phones across a busy 100MB link without QOS and without call quality problems. I would however, if given the choice, implement QOS if only for piece of mind.

I hope this helps.

Andrew

 

[PotNoodleBoy]

Andrew,

Thanks for the info. I've always thought that it would be fine, but as a company we're always cautious! The problem is, that we come from a data/server background and we get undercut by traditional phone companies. Partly becuase they don't pay as much attention to these things.

 

[PotNoodleBoy]

big70,

You say you only put the IPO in the voice VLAN - do you not use phone manager in these cases?

 

[as1981]

Rob,

I entirely support your view. QoS might not always be necessary but if it's implemented you won't have a problem, if it isn't you might and it's not worth the hassle (trust me!).

As a comment to your question to big70 we only have the IPO in the voice vlan (IP office 4.6 v2 so I don't think we have a choice) and use a layer 3 device to route back to the data lan. I'm not saying it's the best method as I wouldn't know I am just saying we have it setup like this and it can work. From a networks point of view I would have thought having the IPO in both lans would make sense but if this any particular affects on the IPO or Avaya software I can't comment.

Thanks

Andrew

 

[PotNoodleBoy]

PlatinumGuy,

Thanks for the info - it's just occured to me why your advice is so important. As you say, BLF updates won't reach the PM's if the IPO is on the voice VLAN.

Assuming I don't plug the IPO in to the network twice, once for each VLAN, I'm guessing the following scenario should work:

Data VLAN - 192.168.1.0
Voice VLAN - 192.168.2.0

IPO on 192.168.1.1

A phone should be given the call server IP of 192.168.1.1 and a default gateway of a layer 3 switch which can route between vlan's. The only problem I can see is that I have about 4 of these 3com switches all with IP phones plugged in to them. It would seem I need to select one as my phone's default gateway.

Phew this is getting difficult!

 

[ProviderReborn]

Have a peak at this document.

http://members.optusnet.com.au/hagoo/iporesource/IP Office VLAN MR IPO.pdf

ACA - IP Office Implement
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