Cisco ATA 186/188, FXS & FAX

ATA 186 – 2 x voice ports + 1 x RJ-45 10BaseT port ATA 188 – 2x voice ports +  2 x RJ-45 10/100BaseT port The Cisco ATA supports two modes of fax services, in which fax signals are transmitted using the G.711 codec. It cannot support fax relay. ATA is accessed by web through http://<ipaddress_of_ata>/dev •Fax pass-through mode—Receiver-side Called Station Identification (CED) tone detection with automatic G.711A-law or G.711µ-law switching. •Fax mode—The Cisco ATA is configured as a G.711-only device. Fax Pass-through Mode: Fax pass-through mode allows for maximum codec flexibility because users may set up a voice call … Continue reading Cisco ATA 186/188, FXS & FAX

Scenario#18 – Cisco 7936 will not register

I was looking into this issue for a customer where a Conference phone, Cisco 7936, was not registering to Call manager. When I looked the MAC address of it in Call manager, it was in the status of ‘unregistered’ and there was an IP address assigned to it as well. This suggests that it somehow reached to Call manager but then got unregistered OR this phone was registered to Call manager some time in back. There were some other 7936 phones as well which were all registered fine. I asked them to do a factory reset of the 7936 phone … Continue reading Scenario#18 – Cisco 7936 will not register

Scenario#10 – Phones showing Incorrect time

I don’t remember how many times I came across customers complaining that their phones are either x minutes ahead or x minutes behind the normal time. This is what I do whenever I come across time issues. This is for applicance based Call manager (5.x, 6.x, 7.x, 8.x) Go to OS Admin > Settings > NTP server Is there any NTP Server? If there is an IP address mentioned then try to Ping that IP from OS Admin > Services > Ping Most of the time customers add the CUCM IP address as NTP address. This is not correct. Under … Continue reading Scenario#10 – Phones showing Incorrect time

Scenario#9 – 3x 7975 Phones not showing Correct time

First step was to check if the Call manager is all synched and showing current time. Call manager was sysnched with an external NTP source (a gateway) and was looking good. Customer told me there were some Phone load issues. I found that the 7975 display debug shows it’s looking for a 4S load but cannot find it. I checked it under OS admin and the load was there. I checked the device pack which was compatible with the load. I reset the phone but the result was same.  I then RESTARTED the TFTP service and all worked fine. The … Continue reading Scenario#9 – 3x 7975 Phones not showing Correct time