10g for voip?

[m.matteson]

i'm busy talking to my manager and her is convinced that we NEED a 10G network for 200 people because we are rolling out a voip solution. I told him we have 3750s in 3 areas of the building connected via SFPs. are enough, if we need more bandwidth between them we could use etherchanel over copper. can anyone help me out with this? why we do or don't need it? thanks. btw every client has a 1g connection. the network is already 1G

[szahid]

Hi :

One thing to note is you already have a Gig enabled network. When we used to have FE in access layer , we were aggregating the access layer with the Gig uplinks. Now that we have Gig in the access layer , we need to have a higher bandwidth uplinks ( like 10 Gig ) to aggregate the access layer. You are right that voice certainly does not need all this bandwidth . Voice is anyway low bandwidth app. The need for bandwidth is for the data applications.

You may have a Gig links going to each user and they may not be using all the bandwidth available to them , but not very far from today , there will be applications that will be using all the available bandwidth and thats exactly when you will need 10 Gig uplinks.

thanks

Salman Z.

[dgahm]

A G711 uncompressed VOIP call takes 80kb plus ethernet overhead. Use 100kb per call to be conservative. So 200 simultaneous calls would consume 20mb/s. All 200 users will never be on the phone at the same time, and the traffic would not all be on the same link, but if they were you are looking at 2% of a gig link, or .2% of a 10 gig.

It would be cool to run 10g, but your manager needs a better reason than voice.

[bkaren1278]

Cisco VOIP phones have a 10/100 switch in them. So if you wish to use power over ethernet and use the switch internal to the phone there is no benefit recognized to a 10g network at least not on the access layer side.

[travis-dennis_2]

And if you want to keep Gig connectivity you can get the 7971G phone with a 10/100/1000 inegrated switch.

http://www.cisco.com/en/US/products/ps5946/index.html

[m.matteson]

well money is no issue, so maybe it would be cool to make it 10G. imagine all the movies i could transfer. haha