sundance-communications.com/forum Forums Other TDM Phone Systems ESI Telephones & Systems Major Problem with ESI and faxing

We are having continous on-going major problems with ESI and the continuation of failures with fax machines.

One of our sites is a 600 with an Interface version 3 running program 16.04.34.

The other site is a 1000 with an Interface version 1 and running 18.04.22.

These sites are at opposite ends of our state and the problem that we have major and multiple slip errors occuring......after talking to some of the techs at ESI and other folks in the know it appears thatt he slips on the PRI are being caused by these versions but cannot seem to get a fix for it (or something of the sort).

The problem with the faxes is that one out of every 3 or 4 attempts do NOT go through and large multi-page faxes only get about two-thirds through before "poor line condition" appears and the transmission is halted.

Does anyone have any knowledge of ths at all?

If so, any insight would be greatly appreciated as always.

Out of curiosity, who is the service provider? Are they delivering via a softswitch/ IAD combination? If they do not have the clocking set up properly on their end, it could cause problems as well.

Also if the service provider is running any sort of IP transport and they are not utilizing T.38, you will have fax issues.

In my experience if its a "Traditional" PRI from verizon coming in on copper to a biscuit jack, you are good to rx Fax's

I have seen problems with these "emulated PRI's" that look like a PRI to the phone switch but and actually re-created customer end from a pure IP stream via some device like an ADTRAN box. its also near impossible to modem in over these type PRI's also.........

I agree with both posts above and if that is the case you may just want to order a POTS line for each site......if you have traditional T's and are getting slips like that request a pair change from the telco.

If this on a Communication Server check mailbox 598 for errors.

One major issue is that many providers only enable G.729 to save bandwidth. Faxing is going to fail left and right over a compressed codec.

If they are using a softswitch/IAD combo, you may want to disable ECM and set the baud rate to 9600 on the fax machine.

I work for a provider and our fax service works pretty well. I see fax logs from customers, and we often see 50+ page faxes. I have done a 300 page fax from the PSTN to a customer on our softswitch. However, I am running T.38 on all endpoints, and have G.711 fall back. We also have some strict QoS settings across our backbone.

As for modem connection, it is hit or miss. I wish all of our equipment supported ITU V.150.1.

Don't be fooled by a traditional biscuit on the wall! We install an Adtran IAD on premise, however I know of a few providers that put the Adtran in the CO and deliver the PRI / T1 CAS connection over a standard P2P T1 circuit.