Level 3 V.92 Modem-on-Hold (MoH)

Level 3 V.92 Modem on Hold (2-Apr-03)

In March 2003, Level 3 changed the Modem-on-hold default on its network of V.92 access numbers from "ON" to "OFF".

This change was requested by some of Level3's customers who do not want to provide support for this V.92 feature. Level3 provides wholesale access numbers to a large number of ISPs - both small and large. Level3 customers include nearly all of the largest ISPS - including AOL, MSN, Earthlink, etc. These large ISPs usually contract with a number of different wholesale access providers - only numbers provided by Level3 have any V.92 server modems.

Some ISPs were affected by this Level3 change: Modem-on-hold is now enabled only for Level3 ISPs that request it. MoH is not active until after the customer has logged on. This means that it is not possible to determine whether a Level3 ISP supports MoH unless you are a customer that can log on to that particular ISP:

When the Level3 modem connects, MoH is disabled. After the DUNs login completes, Modem-on-hold is enabled if that ISP has requested MoH capability from Level 3.

This change means that some customers of major ISPs, including AOL, that were calling Level3 numbers and enjoying V.92 MoH are no longer able to do MoH.

If a call comes in after the modem has connected, but before the login to the ISP has completed, a MoH request will be denied. This prevents testing MoH using Hyperterminal without logging in to the ISP. (Note also - most V.92 modems cannot detect an incoming call during a handshake or retrain.)

Some Level3 ISPs that promote V.92 and MoH were not aware of Level3's change, and MoH capability lost until Level3 updated MoH setting for the affected ISP. Some Level3 ISPs have decided not to allow MoH, but may still list or advertise access numbers as "V.92". Finding an ISP supporting MoH is not as simple as finding one with "V.92".

While Level3 is the largest national provider of V.92 access numbers, there are many local and regional ISPs providing V.92 access. Most of these ISPs support MoH, and have it enabled by default. You can verify MoH capability with these ISPs by connecting to them with Hyperterminal. You can determine whether a particular access number is provided by Level3 by dialing that number in Hyperterminal, pressing Enter - if the text:

Level 3 Comm xxxxxxxxxxxxxx

is received, the number you dialed is provided by Level3.