Solved

VOIP QOS deployment

Posted on 2008-06-26
5
620 Views
Last Modified: 2013-12-27
I am new to QOS so please bear with me.
This is a very basic sketch of my network.

                                   (Site-2-Site VPNs)
Multiple remote sites ------> WAN  <------ 2800 <-----ASA 5510 <----- 2960(G) ---[ LAN with BCM400.

I have started using VOIP between some locations but I am concerned about the implications of not having QOS network wide.
    1. Should I configure QOS on every device (2800, ASA 2960(G) switches etc)?
    2. 20 Remote sites will each have a max of 2 IP/Softphone (Nortel & Cisco) and has 1mb down and    atleast 256kbps upload speeds how would you recommend we allocate bandwidth for VOIP?
       N.B codec: cisco g729 and nortel g711.
If i am missing anything please help!


If I have to configured QOS on each device  
0
Comment
Question by:coolcorp
  • 2
5 Comments
 
LVL 36

Expert Comment

by:grblades
ID: 21881735
You should configure QOS on all devices that directly connect to the WAN.
QOS is used to decide what packets to drop on a congested line so you only need to configure it on equipment which sits between a high and a lower bandwidth connection.

You should also configure it on the switches if they have the capability. How important this is depends on whether the phones have their own dedicated network port or whether computers daisy chain off the back of the phone. Also if you have servers with gigabit network connections this has an effect aswell.

You will also need to enquire with the WAN provider to make sure the WAN itself supports QOS.
0
 

Author Comment

by:coolcorp
ID: 21900302
Thanks grblades,
I have a few phones that are daisy chained and Data and VOICE share the same network.
Yes we have servers with gigabit connections as well.
How drastic do think this will be and what approach you think i should take?
Also there may be an issue creating a seperate network for VOICE.
I am also thinking that if the phones are going to be daisy chained then data and voice will have to be on the same network?
Please guide me?
Thanks.
0
 
LVL 36

Accepted Solution

by:
grblades earned 500 total points
ID: 21900909
No you can still have the phones on a different VLAN even if the computers are daisy chained off the back of them. You just set the switch to enable 802.1q trunking and set the voice VLAN number to be permitted over the trunk. Then on the phones you configure them to perform VLAN tagging. Then all voice traffic is sent over the VLAN while normal data is untagged and so goes over the default VLAN the port on the switch is configured to use.
You certenly dont have to keep voice and data separate in this fashion. Often people use voip clients on their pc's or have some management panel running on their pc so the networks have to be combined and often it is easier to run it all over a single network anyway.

I would setup a test. Get a phone and daisy chain a pc off the back of it. Make a call and then try and copy a very large file to and from the pc and see if you can hear anything during the phone call. If possible try it will a ftp file transfer to the server with a gigabit network connection as this will be worst case. Windows file sharing is far less efficient than ftp so if ftp does not cause a problem copying a file in windows shouldnt either.

Configuring a switch to use QOS is normally fairly easy. It really easy if you dedicate a VLAN for voice as cisco switches have a preset configuration for this that you practically just need to turn on.
If you are sharing the voice and data you need to configure the switch to trust the difserv/tos (QOS indication flags in the packet headers) that the phones set automatically so it doesnt really make much difference.
0

Featured Post

3 Use Cases for Connected Systems

Our Dev teams are like yours. They’re continually cranking out code for new features/bugs fixes, testing, deploying, testing some more, responding to production monitoring events and more. It’s complex. So, we thought you’d like to see what’s working for us.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

There are no good configuration guides for HP-H3C router to LYNC on the web. :( Big statement, but we havent been able to find one yet. We did find the following document useful, but the information was not enough to use H3C router for use as a L…
Implementing Avaya's One-X portal is pretty painless, until you want to deploy this to the Android and iPhone clients when these clients are outside of your network. The clients will also work within your local network. Here is our experience and so…
Internet Business Fax to Email Made Easy - With eFax Corporate (http://www.enterprise.efax.com), you'll receive a dedicated online fax number, which is used the same way as a typical analog fax number. You'll receive secure faxes in your email, fr…
With the power of JIRA, there's an unlimited number of ways you can customize it, use it and benefit from it. With that in mind, there's bound to be things that I wasn't able to cover in this course. With this summary we'll look at some places to go…

911 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

20 Experts available now in Live!

Get 1:1 Help Now