Data connection slows down on PCs plugged into back of i2004s

[jamerein]

I have a BCM 400 running Release 3.7 with all patches current to 03/23/07.

The customer has Cisco Layer 3 switches and LAN1 on the BCM is plugged into a port on the Cisco switch that tags the packets for VLAN2. There is no VLAN priority setup on these switches.

All of my i2004 phones use VLAN2 and the data uses VLAN1. Each phone has a computer plugged into the back of it at each work station.

The customer has noticed that several of the computers plugged into the backs of the phones experience slower data transfers than before the IP phones were in place. They've run several tests and these tests also show the data speed reduced.

They have found that unplugging the power to the phone and resetting it causes that transmission to speed up by 4x. This will remain like this for a while but it eventually slows down again.

I've contacted Nortel tech support but they really couldn't help so I'm searching the web for possible solutions.

The customer is doing all of their own configurations on the Cisco switches so I just need to advise them of some things to try and they will do it.

Anything you've got is great!

 

[gberger]

Had a similar problem before at a customer site. The IT guy programmed the speed to 100mbs-full duplex on the last
4 I2004 we send him. As soon as i switched it back to "auto" the download speed on the pc's attached to these
ip phones came back to normal.
Let me know if it fixes your problem.

 

[pandster]

Same problem on BCM50R1 with Netgear PoE L3 switch. Restarting phone can cure. My plan was to see if BCM50 R2 solved problem and if not look to a cisco switch. All my phones are set to 100 Full as are the PC's. Some of the PCs had realtek chipset which didn't perform well on Auto speed and duplex. I will be interested to see if anyone else has the problem and also has a solution.

 

[MagnaRGP]

As gberger indicates, you have a duplex mismatch. Phones should be set to AUTO as should the switches.

 

[pandster]

sorry, dont agree. If both switch and phone are set to full then it should work. It is pretty much standard practice to set the switches locked to full duplex and do the same with connected devices.