Jared Mauch's VoIP Page

I've been operating various VoIP devices for several years, including the following VoIP devices. A few different people have seen the same problems that I have, so I'm including my tips and tricks here:
Cisco DHCP Configuration help for IP Phones
VIC-2FXS (800-02493-xx)
VIC-2FXO (800-02495-xx)
VIC-2FXO-M1 (800-05298-xx)
VIC-2BRI-S/T-TE (800-03803-xx)
Cisco 7920 Skinny/SCCP (CP-7920)
Cisco 7960/40 SIP (CP-7960G CP-7960 CP-7940 CP-7940G)
Cisco 7970 Skinny/SCCP (CP-7970G)
Cisco ATA 186 & Vonage Unlock (ATA186-I1)
Hitachi Cable WIP-5000/Wireless IP 5000 802.11b SIP phone (WIP-5000 WirelessIP-5000)

Cisco 7920

The Cisco 7920 is a Wireless (802.11b, aka WiFi) IP Phone. Presently it only supports the Call Manager protocol (also known as Skinny or SCCP).

Some phones require a unlock sequence in order to allow access to all the menu choices. In this case, try this sequence: Menu, *, #, #, Send (green phone icon).

If you are configuring a large number of these phones, I recommend using the 7920 USB Configuration Utility. This will require you acquire the USB Cradle (US$95) and the Software (US$250). Don't forget to set an IP on your 7920 network adapter in your control panel. (See step 11 on this page.)

If you are having problems pinging your 7920, turn off power saving mode. This can be found under Phone Settings->Power Save after entering the "Menu", *, #, #, Send sequence.

Cisco 7960/40

The Cisco 7960/40 presently is my favorite SIP device out there. The large LCD and support for SIP make it an excellent desktop phone. While somewhat cost prohibitive for the starting hobbist (they can be found for about $150-350 on

Here's my important tips/tricks:
To reboot the phone without pulling the power, press * (Asterisk), 6 and Settings (sometimes represented by a Check Box) at the same time.

Another neat feature I found is a way to view the live RTP stats of a call in progress. When on a call, press your ? (or sometimes i) key which is in the center of the mailbox/directory/services/settings area). It will show you the Codecs in use, Jitter, Tx/Rx packet counts, and packet loss data. Very useful if your users are behind slower connections or having strange audio issues.

Cisco 7970

The cisco 7970 is a Color IP phone. I've found that doing a full factory reset is useful. Instructions are easy, and found

There have also been a number of software troubles with this phone. It is STRONGLY recommended to use the latest software on this phone. You can find it here.

If you are trying to make the 7970 work with Asterisk you will need to check out the chan-sccp driver from CVS and apply a simple patch. I did not write it, but it works for me.

DHCP Configuration Help

DHCP Config for IOS, specifying as the TFTP server
ip dhcp pool wired_lan
   domain-name example.com
   option 66 ascii ""

Same config, but statically assign phone IP, for ISC DHCP server:

host mysip7960 {
    hardware ethernet 00:03:6b:00:00:00;
    option routers;
    option tftp-server-name "";

Cisco ATA 186

Current Firmware for SIP is v3.2.1 atasip (050616A) (2005-06-16)

I have been working on this device for some time and am offering offering an "Unlock" service for the ATA-186 devices that are revision A0. You can find this number on the bottom of your device (74-2916-01 Rev.A0). The flash chip is socketed in the hardware revision A0, so you can ship me the chip and I will reset it for you for US$15. You will need to send it properly packaged and I will return it via USPS Parcel Select (Shipping will be higher outside US48, contact me for updated pricing or bulk discounts if you want a higher shipping SLA). Contact me via e-mail if you are interested in this service.

For the Rev.B0 and C0 devices, you can pay someone to unsolder the flash and and provide you the unlock code. I also offer the service for $25. (includes return USPS shipping)

You can find replacement Flash chips online but you still need to load the firmware on them, there is no default firmware stored elsewhere in the device, infact the second half of the chip (0x40000-0x7ffff) is usually the FACTRESET firmware. This seems to have changed in newer software.

Hitachi Cable Wireless IP 5000/WIP-5000

The current firmware is v2.1.11

I have been hacking and unlocking most of the config options that are available, including the hidden ones in the firmware (1.5.10).

here is a link to a user.ini file that will unlock most of the hidden options, USE AT YOUR OWN RISK.

This phone runs a web server on tcp port 8080, it also runs a debug/tracing client on port 3390. There is also a snmp agent on the phone with a read-only community of 'public'. It identifies itself as "ucd-snmp-4.1.2/Red Hat eCos". *WARNING* it also includes a read-write snmp community of 'private'

There is a hidden webpage which lists current files on your flash filesystem. Beware of people fetching internal.ini as it will include your full config including passwords. Same goes for web.ini.

The 1.5.10 version also includes OpenSSL version 0.9.6b (9 Jul 2001) which has a few security advisories against it.

© 2004-2008 Jared Mauch - jared+home@puck.nether.net