Messages

1

Mitel MiVoice Business/MCD/3300 / Re: Mitel phones not liking the SYN/ACK

« on: September 04, 2013, 08:45:27 AM »

Thanks Ralph. From the captures, you see any reason as to why the phones might not be registering ?

2

Mitel MiVoice Business/MCD/3300 / Re: Mitel phones not liking the SYN/ACK

« on: September 04, 2013, 02:50:28 AM »

Hello Ralph, its all static IP addresses. Also, I was wondering if its possible for Mitel phones to register via UDP instead of TCP. Is it possible?

3

Mitel MiVoice Business/MCD/3300 / Re: Mitel phones not liking the SYN/ACK

« on: September 03, 2013, 08:58:49 AM »

They are connected to the same switch. It's just that the captures were taken on different phones . If you want we can try to take a working/non-working for the same phone but they the difference is still the same.

parvikram
CCIE (R&S)

4

Mitel MiVoice Business/MCD/3300 / Re: Mitel phones not liking the SYN/ACK

« on: September 03, 2013, 08:26:29 AM »

Hi Ralph,

  Let me upload it again. If you still can't open, then let me know your email address. I will send it across.

5

Mitel MiVoice Business/MCD/3300 / Re: Mitel phones not liking the SYN/ACK

« on: September 03, 2013, 08:21:29 AM »

The issue is that the Mitel phones are not reigistering with the Voice server. The Voice Server IP is 172.16.8.2.

6

Mitel MiVoice Business/MCD/3300 / Re: Mitel phones not liking the SYN/ACK

« on: September 02, 2013, 06:46:50 AM »

I'm attaching the working and non-working captures. You can see that in the non-working one, the phone receives the SYN/ACK but does not respond with an ACK. I do not suspect routing since, the same phone is communicating with a different TCP port 20001 on the same server. But this time, the traffic is UDP. I seriously still think , its something to do with the TCP stack of Mitel . I know it's been working for ages, but we do see it pretty obvious here, that with a few TCP options realigned and a different MSS value than the working capture, the phone does not respond with an ACK.

7

Mitel MiVoice Business/MCD/3300 / Re: Mitel phones not liking the SYN/ACK

« on: August 28, 2013, 03:13:37 AM »

Thanks Ralph. But I'm not getting any answer. I really suspect some bug in the TCP Stack of the Mitel phone. I wanted to confirm the same.

8

Mitel MiVoice Business/MCD/3300 / Re: Mitel phones not liking the SYN/ACK

« on: August 27, 2013, 09:41:44 AM »

Hello Ralph,

  Thanks for the response. It's a Mitel phone connecting to a Mitel Voice Server.  Not sure about the version and exact make. Do you need me to find that out ? I can if it helps.

9

Mitel MiVoice Business/MCD/3300 / Mitel phones not liking the SYN/ACK

« on: August 27, 2013, 05:17:20 AM »

I have two captures. In one, I see a handshake from the phone to the Voice Server (working capture). In the non-working one, I do not see an ACK from the client after the SYN/ACK from the Voice Server.

Initially I thought it might be a routing issue since maybe the SYN/ACK from the server is not reaching the client or the ACK from the client is not reaching the server. But traffic other than Voice is going fine back and forth between the client (Mitel Phone) and the server. There is no FW between them.

Any idea why we do not see any ACK from the Mitel phone back only for the Voice traffic. I thought maybe something in the SYN/ACK which the phone is not liking perhaps. I saw the TCP options , in the failing case the order of appearance of the TCP options is different. The fingerprint of the failing scenario shows the windowscale option first, followed by MSS and NOP. The successful scenario shows MSS,NOP,Windowscale .
WOULD THIS CAUSE THE MITEL PHONE TO NOT SEND BACK AN ACK SINCE THE PHONES ARE NOT REGISTERING.