HI All,
As i keep saying TATA/TTML/TPBC and thier E1 have given us horrid times.
Their link commissioning has been a real nightmare with over 200 man hours spent on every link that we took from them.
The problem:
1) End to End BERT from TATA/TTML/TPBC comes errors free when run over hours/days/etc.
However the moment its put up on our Cisco Routers the Links shows heavy input errors, CRC, Runts , Frame errors and et all.
2) Extended Ping using point to point serial IP with data pattern 0xFFFF tests 100% successful. However Extended Ping using point to point serial IP with data pattern 0x0000 tests miserabley. Sometimes below 85%
Observation:
TTML did try a lot of things including changing modems at both ends, changing last mile access, changing the tranmission path to include Tejas Networks Mux at both ends. However nothing succeeded.
At the end TATA/TTML/TPBC escalated the problem to their Modem Vendor (Loop).
Basically Loop provided a different firmware enabled modems. Yet no luck.
At the end Loop provided a Cisco Document to TATA/TTML/TPBC which mentions about Cisco manufacturing the Serial Port Cards (WIC-2T, NM-4T, etc) out of two locations , one in Singapore & other in China.
We are still to get hold of this doc as yet.
However the China Cards can only support an E1 upto 1984Kbps whereas the Singapore Cards can support upto 2Mbps.
Thus if you have a China Card at one End and a Singapore Card at the other & if the Link and the Modems are configured at 2Mbps Unframed....You are in a soup. The Link gives heavy errors.
Thus TATA/TTML/TPBC configured the Loop modems for 1984Kbps framed with TTM option ON on their Loop modems to give us the E1.
phew, such a lot of pain for the customer. Not to mention the time and money lost of the delay in delivery. Moreover there is no way to identify your card make once the card is installed.
Now if you were unlucky enough like we were, and if you have a G.703 (E1/T1 controller at one end), then you need to configure the controller in frmaed mode as well
I paste the config below for all to use.
controller E1 3/2
framing NO-CRC4
channel-group 0 timeslots 1-31
!
interface Serial3/2:0
ip address 10.10.10.10 255.255.255.252
no ip proxy-arp
end
