I've been asked many times just what is available to be placed in a 'sip' configuration file and what items can be changed on a phone.

Before we show the list, let's get a few things out of on the table first.

'sip' only. We'll only address the options available with the 'sip' protocol on this page. And we're using sip ver. 8.x for our 'source of info'. We all know (hopefully) that you can have only one protocol (sip, sccp, or mgcp) loaded on the phone at any one time. But some of the settings for these protocols (i.e. 'Network') are much the same for all. If you're not using 'sip', you're free to read along but we can't guarantee this will help much.

Let's look at the above and work backwards. Some items on the phone can be changed by the user without "unlocking" the phone. These are "user settings". Many items (Network & Sip settings, etc) can be changed on the phone if it is "unlocked". Lastly, some items must only be changed using a configuration file loaded into the phone via TFTP server when the phone boots.

Gotch'a #1 - In some cases, if a particular setting you could set on the phone existed, if you make a 'special' change via a 'config' file that option is no longer available on the phone.

Loading config files. When the 'sip' phone boots and contacts the TFTP server, it asks for two config files in order. They are "SIPDefault.cnf" and SIP[mac address].cnf - Either of these files can contain any of the configuration items we discuss below.

Gotch'a #2 - Previously stated, you put the sip configuration 'items' in ither 'SIPDefault.cnf' -or- 'SIP[mac address].cnf', either will work. - but - Please remember that "SIPDefault.cnf" loads first and "SIP[mac address].cnf loads second. If you have anything in the "SIP[mac address].cnf" that differ from anything in "SIPDefault.cnf", the ones in "SIP[mac address].cnf" will be the ones the phone uses. - To keep confusion down, it's best to ONLY put "phone specific" items in "SIP[mac address].cnf".

Finally - You don't have to put ALL the settings we list in your config file(s). If the phone doesn't see a particular setting, it will revert to whatever is stored in its flash memory.

anonymous_call_block - Optional - Configures anonymous call block.
Valid values:
0 - Disabled, but can be turned on and off using the user. When disabled, anonymous calls are received.
1 - Enabled, but can be turned on and off using the user. When enabled, anonymous calls are rejected
2 - Disabled permanently and cannot be turned on and off locally by the user. Specify this parameter in the phone-specific configuration file.
3 - Enabled permanently and cannot be turned on and off locally by user. Specify this parameter in the phone-specific configuration file.
Factory default is 0

auto_answer - Optional - Configures the intercom functionality so that the user can define one or more of their lines for this feature. It is an integer field that represents a bit mask of 'on' or 'off' for each line key. The bit mask reads from the least significant bit of 0 equal to line 1 to the most significant bit of 5 for line 6.
Valid values are as follows:
Cisco 7960 - 0 to 63
Cisco 7940 - 0 to 3
Note: This parameter CANNOT be set in the configuration file.
gg Note: If you can figure this one out, let me know.

autocomplete - Optional - Configures automatic completion of numbers being dialed.
Valid values:
0 - The autocomplete feature is disabled by default but can be turned on and off by the user.
1 - The autocomplete feature is enabled by default but can be turned off and on by the user.
2 - The autocomplete feature is disabled and cannot be turned on and off by the user. To set this parameter for a specific phone, configure it in that phone's configuration file.
3 - The autocomplete feature is enabled and cannot be turned off and on by the user. To set this parameter for a specific phone, configure it in that phone's configuration file.
The factory default is 1

call_hold_ringback - Optional - If you have a call on hold and are talking on another call, when you hang up the call, this parameter causes the phone to ring, letting you know that you still have another party on hold.
Valid values:
0 - Off, but can be turned on and off locally using the user interface.
1 - On, but can be turned on and off locally using the user interface.
2 - Off permanently and cannot be turned on and off locally using the user interface. Specify this parameter in the phone-specific configuration file.
3 - On permanently and cannot be turned on and off locally using the user interface. Specify this parameter in the phone-specific configuration file.
Factory default is 0

call_stats - Optional - Includes RTP statistics in BYE requests and responses.
This is a 'Sip' setting.
Valid values:
0 - disable
1 - enable
Factory default is 0
If this parameter is enabled, the phone inserts the headers RTP-RxStat and RTP-TxStat as follows:
RTP-RxStat: Dur=a,Pkt=b,Oct=c,LatePkt=d,LostPkt=e,AvgJit=f
RTP-TxStat: Dur=g,Pkt=h,Oct=i
where the following apply:
Dur - Total number of seconds since the beginning of reception or transmission.
Pkt - Total number of RTP packets received or transmitted.
Oct - Total number of RTP payload octets received or transmitted (not including RTP header).
LatePkt - Total number of late RTP packets received.
LostPkt - Total number of lost RTP packets received (not including late RTP packets).
AvgJit - Average jitter, which is an estimate of the statistical variance of the RTP packet inter-arrival time, measured in timestamp unit and calculated according to RFC 1889.
a, b, c, d, e, f, g, h, and i - Integers.
gg note - Don't enable this if your server can't handle the responses.

call_waiting - Optional - Configures call waiting.
Valid values:
0 - Disabled, but can be turned on and off using the user. When disabled, call waiting calls are not received.
1 - Enabled, but can be turned on and off using the user. When enabled, call waiting calls are accepted.
2 - Disabled permanently and cannot be turned on and off by the user. Specify this parameter in the phone-specific configuration file.
3 - Enabled permanently and cannot be turned on and off locally by the user. Specify this parameter in the phone-specific configuration file.
Factory default is 1

callerid_blocking - Optional - Configures caller ID blocking. When enabled, the phone blocks its own number or e-mail address from phones that have caller identification enabled.
Valid values:
0 - Disabled, but can be turned on and off by the user. When disabled, the caller identification is included in the Request-URI header field.
1 - Enabled, but can be turned on and off by the user. When enabled, "Anonymous" is included in place of the user identification in the Request-URI header field.
2 - Disabled permanently and cannot be turned on and off by the user. Specify this parameter in the phone-specific configuration file.
3 - Enabled permanently and cannot be turned on and off by the user. Specify this parameter in the phone-specific configuration file.
Factory default is 0

cfwd_url - Optional - Configures the call forwarding feature. The maximum allowable characters for the string is 128. The characters can be a telephone number or a URL.
Note: This parameter cannot be set in the configuration file.
gg note - parameter does not appear in a Sip 7.5 phone

cnf_join_enable - Optional - Whether the conference bridge, when it hangs up, should attempt to join the two leaf nodes.
Valid values:
0 - Do not join the two leaf nodes.
1 - Join the two leaf nodes.
Factory default is 1
gg note - parameter does not appear in a Sip 7.5 phone

date_format - Optional - Format for dates being displayed on the top line on the phone (when a SNTP server is configured). Valid values:
M/D/Y - Month/day/year
D/M/Y - Day/month/year
Y/M/D - Year/month/day
Y/D/M - Year/day/month
Y-M-D - Year-month-day
YY-M-D - 4-digit year-month-day
Default is M/D/Y

dial_template - Template with which you specify which file to download for your dial plan.
gg note1 - Very little info is available for this parameter.
gg note2 - Parameter does not appear in a 'Sip 7.5' phone.

directory_url - Optional - URL of the external directory server. This URL is accessed when you select Directory > External Directory. For example,
use directory_url: "http://10.10.10.10/CiscoServices/Directory.asp".
gg note1 - This needs some more research.
gg note2 - 'External Directory' does not appear on a 'Sip 7.5' phone

dnd_control - Optional - Sets the Do Not Disturb (DND) feature.
Valid values:
0 - Off, but can be turned on and off by the user.
1 - On, but can be turned on and off by the user. The phone blocks all calls placed to the phone and logs those calls in the Missed Calls directory.
2 - Off permanently and cannot be turned on and off by the user. Specify this parameter in the phone-specific configuration file.
3 - On permanently and cannot be turned on and off by the user. This setting sets the phone to be a call-out phone only. Specify this parameter in the phone-specific configuration file.
Default is 0

Domain Name - Name of the DNS domain in which the phone resides.
If using DHCP, this parameter is ignored.
If using, its a good idea to put the domain name in double-quotes.
gg note: - I thought parmeters can not have white spaces. - Hmmm.. Need to check this out.

dscpForAudio - Differentiated Services Code Point (DSCP) specifies the class of service for each audio packet.
Valid value is any positive integer.
Factory default is 184.
gg note - Haven't a clue what this means. - Needs research.

automatically adjusted on the phones.
Valid values are:
0 (do not adjust)
1 (adjust)
Factory default is 1

dst_offset - Optional - Offset from the phone time when DST is in effect. When DST is over, the specified offset is no longer applied to the phone time.
Valid values:
hour/minute
-hour/minute
+hour/minute
hour
-hour
+hour
Factory Default: (probably)02:00 (for USA)
This setting is not available on the phone. It MUST be put in a phone's config file to be set.
If "dst_auto_adjust" is disabled, this parameter is ignored.

dst_start_day - Optional - Day of the month on which DST begins.
Valid values:
1 to 31 (for days of the month)
0 (ignore this field and use the value in the dst_start_day_of_week parameter instead)
Factory default is 0
This setting is not available on the phone. It MUST be put in a phone's config file to be set.
If "dst_auto_adjust" is disabled, this parameter is ignored.

dst_start_day_of_week - Optional - Day of the week on which DST begins.
Valid values:
Any of the following: Sunday or Sun, Monday or Mon, Tuesday or Tue, Wednesday or Wed, Thursday or Thu, Friday or Fri, Saturday or Sat, Sunday or Sun
1 to 7 (1 is Sunday; 7 is Saturday)
Name of the day is not case-sensitive.
Factory default: Sunday (in the USA).
This setting is not available on the phone. It MUST be put in a phone's config file to be set.
If "dst_auto_adjust" is disabled, this parameter is ignored.

dst_start_month - Optional - Month in which DST starts.
Valid values:
January, February, March, April, May, June, July, August, September, October, November, and December
1 to 12, with 1 being January and 12 being December
When the name of a month is specified, the value is not case-sensitive.
Factory default: April (in the USA).
Factory default: Sunday (in the USA).
This setting is not available on the phone. It MUST be put in a phone's config file to be set.
If "dst_auto_adjust" is disabled, this parameter is ignored.

dst_start_time - Optional - Time of day on which DST begins.
Valid values:
hour/minute (02/00)
hour:minute (02:00)
Factory default: '02:00' (in the USA).
This setting is not available on the phone. It MUST be put in a phone's config file to be set.
If "dst_auto_adjust" is disabled, this parameter is ignored.

dst_start_week_of_month - Optional - Week of month in which DST begins.
Valid values: 1 to 6 and 8 (1 is the first week; each subsequent number is a subsequent week; 8 is the last week in the month regardless of which week the last week is). Factory default: 1 (in the USA)
This setting is not available on the phone. It MUST be put in a phone's config file to be set.
If "dst_auto_adjust" is disabled, this parameter is ignored.

dst_stop_day - Optional - Day of the month on which DST ends.
Valid values:
1 to 31 (for the days of the month)
0 (ignore this field and use the value in the dst_stop_day_of_week parameter instead)
Factory default is 0
This setting is not available on the phone. It MUST be put in a phone's config file to be set.
If "dst_auto_adjust" is disabled, this parameter is ignored.

dst_stop_day_of_week - Optional - Day of the week on which DST ends.
Valid values:
Sunday or Sun, Monday or Mon, Tuesday or Tue, Wednesday or Wed, Thursday or Thu, Friday or Fri, Saturday or Sat, Sunday or Sun
1 to 7, with 1 being Sunday and 7 being Saturday.
When the name of the day is specified, the value is not case-sensitive.
Factory default: Sunday (in the USA)
This setting is not available on the phone. It MUST be put in a phone's config file to be set.
If "dst_auto_adjust" is disabled, this parameter is ignored.

dst_stop_month - Optional - Month in which DST ends.
Valid values:
January, February, March, April, May, June, July, August, September, October, November, and December
1 to 12 with 1 being January and 12 being December.
When the name of a month is specified, the value is not case-sensitive.
Factory default: October (in the USA)
This setting is not available on the phone. It MUST be put in a phone's config file to be set.
If "dst_auto_adjust" is disabled, this parameter is ignored.

dst_stop_time - Optional - Time of day on which DST ends.
Valid values:
hour/minute (02/00)
hour:minute (02:00)
Factory default: 02:00 (in the USA)
This setting is not available on the phone. It MUST be put in a phone's config file to be set.
If "dst_auto_adjust" is disabled, this parameter is ignored.

dst_stop_week_of_month - Optional - Week of month on which DST ends.
Valid values:
1 to 6 and 8, with 1 being the first week, each number thereafter being subsequent weeks, and 8 being the last week in the month regardless of which week the last week is.
Factory default: 8 (in the USA)
This setting is not available on the phone. It MUST be put in a phone's config file to be set.
If "dst_auto_adjust" is disabled, this parameter is ignored.

dtmf_avt_payload - Optional - Configures the payload type for Audio/Video Transport (AVT) packets.
Valid values:
from 96 to 127
If the value specified is null or invalid, the default value of 101 is used.
This setting is not available on the phone. It MUST be put in a phone's config file to be set.

dtmf_db_level - Optional - In-band DTMF digit tone level.
Valid values:
1 - 6 dB below nominal
2 - 3 dB below nominal
3 - nominal
4 - 3 dB above nominal
5 - 6 dB above nominal
Factory default: 3
This setting is not available on the phone. It MUST be put in a phone's config file to be set.

dtmf_outofband - Optional - Configures the out-of-band signaling (for tone detection on the IP side of a gateway).
Note The Cisco SIP IP phone supports out-of-band signaling using the AVT tone method.
Valid values:
none - Do not generate DTMF digits out-of-band.
avt - If requested by the remote side, generate DTMF digits out-of-band (and disable in-band DTMF signaling); otherwise, do not generate DTMF digits out-of-band.
avt_always - Always generate DTMF digits out-of-band. This option disables in-band DTMF signaling.
Factory default: avt

dyn_dns_addr_1 - Optional - IP address of a new dynamic DNS server. If a new DNS server address is specified, it is used for any further DNS requests after the phone uses the initial DNS address upon bootup. The DNS addresses are used in the following order: 1. dyn_dns_addr_1 (if present)
2. dyn_dns_addr_2 (if present)
3. DNS Server 1
4. DNS Server 2
5. DNS Server 3
6. DNS Server 4
7. DNS Server 5
The dynamic DNS address is not stored in flash memory. Only dotted IP addresses are accepted. This value can be cleared by removing it from the configuration file or by changing its value to a null value " " or to "UNPROVISIONED."
Note The dynamic DNS address is not stored in flash memory.
gg note - This shows up on the phone's 'Network Settings' but I can't edit it even with the phone's unlocked & DHCP turned off. - Config file item only?

dyn_dns_addr_2 - Optional - IP address of a second dynamic DNS to be used for DNS requests. See dyn_dns_addr_1 for more information.

dyn_tftp_addr - Optional - IP address of a new dynamic TFTP server. After initially querying the default TFTP server, the phone rerequests the default and phone-specific configuration files from the new TFTP server. The dynamic TFTP server address is not stored in flash memory. The number of dyn_tftp_addr values supported by the phone is limited to prevent the phone configuration being downloaded repeatedly from multiple TFTP servers.
Only dotted IP addresses are accepted. This value can be cleared by removing it from the configuration file or by changing its value to a null value " " or to "UNPROVISIONED."
gg note - Like the two above, I can't get it to work. - Config file item only?

enable_vad - Optional - Enables voice activation detection (VAD).
Valid values:
0 (disable)
1 (enable)
Factory default: 0

end_media_port - Optional - Configures the Real-Time Transport Protocol (RTP) end range for media.
Valid values:
16384 to 32766
Factory default: 32766.

garp_enable - Optional - Enables Gratuitous ARP for the phone.
Valid values:
0 - GARP is disabled.
1 - GARP is enabled.
Factory default: 1 - enabled

Host Name - Unique host name assigned to the phone. The value in this field is always SIPmac where mac is the MAC address of the phone.
This parameter cannot be changed.

http_proxy_addr - Optional - IP address of the HTTP proxy server. You can use either a dotted IP address or a DNS name. If you use a 'null' value, the word "UNPROVISIONED" shows up in the phone's Network Config setting screen.
Factory default: null

http_proxy_port - Optional - Number of the HTTP proxy port.
Vaid values: any port number
Factory default: 80

image_version -required?- Firmware version that the phone should use. Enter the name of the image version as it is released by Cisco. Do not enter the filename extension (.bin).
Note You cannot change the image version by changing the filename because the version is also built into the file header. Trying to change the image version by changing the filename causes the firmware to fail when it compares the version in the header against the filename.
gg note - Is not available on a 'Sip 7.5' phone.

linex_authname -Optional but required if you need to log into a SIP server.- Name used by the phone for authentication if a registration is challenged by the proxy server during initialization.
It is required only if a proxy server requires authentication from phones. If a value is not configured for the linex_authname parameter when registration is enabled, the default name is used.
Factory default is UNPROVISIONED
The x argument:
'linex_authname' is in reality: 'line1_authname', or 'line2_authname', etc. The values for 'x' can be:
1 or 2 (Cisco 7940 phones)
1 - 6 (Cisco 7960 phones)
gg note - We use these phones a lot with Asterisk servers. - We usually assign the phone number we want the phone to register with the server as it's authx_authname value.
This setting should be placed in the phone's specific configuration file.

linex_contact - Optional - The URL that appears in the contact field for SIP messages on a particular line.
See 'linex_authname' for our discussion on the 'x' modifier.
Factory default: null
gg note - Doesn't show on a 'Sip 7.5' phone.

linex_displayname - Optional - Identification as it should appear for caller-identification purposes. For example, instead of jdoe@company.com appearing on phones that have caller ID, you can specify User A in this parameter to have User A appear on the called party display. If a value is not specified for this parameter, nothing is used.
See 'linex_authname' for our discussion on the 'x' modifier.
Factory default: ' ' (nothing)
Place this setting in the phone's specific configuration file.

linex_name -phone-specific- Number or e-mail address for use when registering. Enter a number without dashes. For example, enter 555-0100 as 5550100. Enter an e-mail ID without the host name.
See 'linex_authname' for our discussion on the 'x' modifier.
Factory default: null
Place this setting in the phone's specific configuration file.

linex_password - Optional - Password used by the phone for authentication if a registration is challenged by the proxy server during initialization. If a value is not configured for the linex_password parameter when registration is enabled, the default password is used.
When the proxy challenges for authentication, it usually uses the 'authname' as the 'login name'.
See 'linex_authname' for our discussion on the 'x' modifier.
Factory default: UNPROVISIONED
Place this setting in the phone's specific configuration file.
gg note - I know it's a pain to try to remember what all these 'names' are for. But when in doubt, just accept the defaults and don't worry about it. - Until something screws up!

linex_shortname - Optional - Labels a line key with a name other than the directory number.
Valid values: name or phone number (? # of bytes)
Factory default: null
Place this setting in the phone's specific configuration file.

local_cfwd_enable -enabled/disabled- Whether the phone can do local call forwarding.
Valid values:
0 (disable)
1 (enable)
Factory default: 1
This option is NOT available on the phone menu. - To change it, put it in the phone's specific configuration file.

logo_url - Optional - Location of the company logo file. This logo appears on the phone display. The background space allocated for the image is 90 x 56 pixels. Images that are larger than this will automatically be scaled down to 90 x 56 pixels. The recommended file size for the image is from 5 to 15 Kb.
For example, use logo_url: "http://10.10.10.10/companylogo.bmp"
Note This parameter supports Windows 256 color bitmap format only. CMXML PhoneImage objects are not supported for this parameter. Using anything other than a Windows bitmap (.bmp) file can cause unpredictable results.
Factory default: null
This parameter cannot be set on the phone. It MUST be set using one of the configuration files.
gg note - We have dedicated a separate page on creating your own logos for use on your phones. - It's in the same place you found this page. - Check it out!

messages_uri - Optional - Configures the voice-mail number that is dialed when the messages button is pressed. Value is typically a phone number but can be a URI.
Factory default: some number to "comm-pilot" who wants you to pay a bunch of money to collect your messages. - Thank you, Cisco.
This parameter MUST be set in a configuration file.

mwi_status - Optional - Displays the message waiting status.
Note You cannot set this parameter in the configuration file.
gg note - Can't find this setting on a 'Sip 7.5' phone unless I'm confusing it with the "Call Waiting" setting. - Hmmmmmm.

nat_address - Optional - WAN IP address of the Network Address Translation (NAT) or firewall server.
Valid values:
dotted IP address
DNS name
Factory default: null
If this is not set and 'nat_enable' is turned on, the address of your gateway is used.

nat_enable - Optional - Enables Network Address Translation (NAT).
Valid values:
0 (disable)
1 (enable)
Factory default: 0
If NAT is enabled, the Contact header appears as follows:
Contact: sip:lineN_name@nat_address:voip_control_port
If the nat_address is invalid or UNPROVISIONED, the Contact header appears as follows:
Contact: sip:lineN_name@phone_ip_address:voip_control_port -AND- and the Via header appears as follows:
Via: SIP/2.0/UDP phone_ip_address:voip_control_port
If NAT is enabled, the Session Description Protocol (SDP) message uses the nat_address and an RTP port between the start_media_port and the end_media_port range in the C and M fields. All RTP traffic is sourced from the port advertised in the SDP message.
gg note - Ahh! - Got it. - Clear as mud!!

nat_received_processing - Optional - Enables NAT received processing.
Valid values:
0 (disable)
1 (enable)
Factory default: 0
If nat_received_processing is enabled, and the received= tag is in the Via header of the 200 OK response from a REGISTER, the IP address in the received= tag is used instead of the nat_address in the Contact header. If this switch occurs, the phone unregisters the old IP address and reregisters with the new IP address.
This setting can only be made using a phone config file.

network_media_type - Optional - Ethernet port negotiation mode.
Valid values:
Auto - Port is autonegotiated
Full100 - Port is configured to be a full-duplex, 100 - MB connection
Half100 - Port is configured to be a half-duplex, 100 - MB connection
Full10 - Port is configured to be a full-duplex, 10 - MB connection
Half10 - Port is configured to be a half-duplex, 10 - MB connection
Factory default: Auto

network_port2_type - Optional - Configures the device type that is connected to port 2 of the phone.
Valid values:
Hub/Switch
Factory default: Hub/Switch
Note If the value is PC, port 2 can be connected only to a PC. If you are not sure about the connection, use the Hub/Switch default value. Specifying the PC option and then connecting port 2 to a switch results in spanning-tree loops and network confusion.

outbound_proxy - Optional - IP address of the outbound proxy server.
You can use either a dotted IP address or a DNS name.
Factory default: (blank)

outbound_proxy_port - Optional - Port number of the outbound proxy server.
Valid values: any port number
Factory default: 5060
When an outbound proxy is enabled, all SIP requests are sent to the outbound proxy server instead of to the proxyx_address. All responses continue to reconcile the normal Via processing rules. The media stream is not routed through the outbound proxy.
NAT and outbound proxy modes can be independently enabled or disabled. The received= tag is added to the Via header of all responses if there is no received= tag in the uppermost Via header and if the source IP address is different from the IP address in the uppermost Via header.
Keep the following rules in mind:
If a received= tag is in the uppermost Via header, the response is sent back to the IP address contained in the received= tag.
If there is no received= tag and the IP address in the uppermost Via header is different from the source IP address, the response is sent back to the source IP address.

phone_label - Optional - Text to display on the top right status line of the LCD.
This field is for end-user display only and has no effect on caller identification or messaging. For example, a phone label can display "User A's phone."
Valid values: up to 11 characters
Factory default: (blank)
This setting can ONLY be made using a phone config file
gg note - If your label has whitespaces, enclose the entire value in double-quotes. It also looks better if you can add a couple of spaces to the end of the label.

phone_password - Optional - Password to be used for console or Telnet access.
Valid valus: up to 31 characters
Factory default: cisco
This setting MUST be made in a phone config file.
This is the password you use to 'unlock' a phone to make changes.
gg note - We have dedicated a separate page here at Jtech for those who have problems 'unlocking' a phone with an unknown password. - Check it out!!

phone_prompt - Optional - Prompt to display during Telnet or console access.
Valid values: up to 15 characters
This setting can ONLY be made using a phone config file.
Factory default: (blank)

preferred_codec - Optional - Codec to use when a call is initiated.
Valid values:
g711alaw
g711ulaw
g729a
none
Factory default: g711ulaw

proxy_backup - Optional - IP address of the backup proxy server or
gateway.
Valid values: IP address in dotted-decimal notation.
Factory default: (blank)
Note You must specify at least one address in any proxy or the phone cannot register.

proxy_backup_port - Optional - Port number of the backup proxy server.
Valid values: any port number
Factory default: 5060

proxy_emergency - Optional - IP address of the emergency proxy server or gateway.
Valid values: IP address in dotted-decimal notation.
Factory default: (blank)

proxy_emergency_port - Optional - Port number of the emergency proxy server.
Valid values: any port number
Factory default: 5060

proxy_register - Optional - Specifies if the phone should register/login to a proxy server.
Valid values:
0 (disable registration during initialization)
1 (enable registration during initialization).
Factory default: 0
Note You can also use this parameter in a phone-specific configuration file. After a phone has initialized and registered with a proxy server, you can remove the registration by changing this value to 0 in the phone-specific configuration file. To reinitiate registration, change the value back to 1.
Note If you enable registration and authentication is required, you must specify values for the linex_authname and linex_password parameters in the phone-specific configuration file.
gg note - KISS - Just use either 1 or 0 and don't bother trying to switch back and forth. - You'll be fine.

proxyx_address - IP address of the SIP proxy servers that are used by the phones.
Valid values:
IP addresses in dotted-decimal notation
FQDN
Factory default: (blank)

The "x" argument:
The value of "x" is number corresponding to the line on the phone that phone number is assigned. Valid values:
7940 phone: 1 or 2
7960 phone: 1 - 6
So in reality, if we were using a 7960 and the phone number is configured on line-3, we would use 'proxy3_address' for the parameter.

If the proxyx_address parameter is provisioned with an FQDN, the phone sends REGISTER and INVITE messages by using the FQDN in the Req-URI, To, and From fields.
If the value of x is not specified in the proxyx_address parameter, the phone uses proxy1_address as the default value.

proxyx_port - Port number of the SIP proxy server that will be used by phone lines other than line 1. The "x" variable represents a phone line. See 'proxyx_address' (above) for our discussion on the "x" variable.
Valid values: any port number
Factory default: 5060
Note For additional phone lines, the proxyx_port parameter and the proxyx_port parameter can be used to assign different proxy addresses to different phone lines. If the value of the "x" is not specified in the proxyx_address parameter, the phone uses proxy1_address as the default.

remote_party_id - Optional - The Remote-Party-ID header supports network verification and screening of a call participant's identity (for example, name and number) and provides privacy for call participants.
Valid values:
0 - Remote party ID is disabled. The phone does not send or accept the remote party ID.
1 - Remote party ID is enabled. The phone sends the remote party ID, and can accept the remote party ID.
Factory default: 0
gg note - Don't see this item on a 'SIP 7.5' phone.

rfc_2543_hold - Optional - Determine the SDP that a phone uses to place a remote party on hold. If this value is 1, the phone uses the RFC 2543 method and sets the media address to 0.0.0.0. If this value is 0, the phone uses the RFC 3264 style and instructs the other side to be in recvonly mode.
Factory default: 0

semi_attended_transfer - Optional - Whether or not the caller can transfer the second leg of an attended transfer while the call is ringing.
Valid values:
0 - Semi-attended transfer is disabled
1 - Semi-attended transfer is enabled
Factory default is 1

services_url - Optional - URL of the services BTXML files. This URL is accessed when the Services button is pressed. For example, use services_url: "http://10.10.10.10/CiscoServices/Services.asp."
Factory Default: ??
This parameter MUST be set using a phone's config file.

sip_invite_retx - Optional - Maximum number of times that an INVITE request will be retransmitted.
Valid value: any positive integer
Factory default: 6
This parameter can only be set using a phone's config file.

sip_max_forwards - Optional - The phone uses the value specified in this parameter in the Max-Forwards header of the SIP requests that it generates.
Valid values: any positive number?
Factory default is 70
This parameter can only be set using a phone's config file.

sip_retx - Optional - Maximum number of times that a SIP message other than an INVITE request will be retransmitted.
Valid values: any positive integer
Factory default: 10
This parameter can only be set using a phone's config file.

sntp_mode - Optional - Mode in which the phone listens for the SNTP server.
Valid values:
unicast
multicast
anycast
directedbroadcast
Factory default: anycast
This parameter can only be set using a phone's config file.

sntp_server - IP address of the SNTP server from which the phone obtains time data.
Valid values: any IP address in dotted decimal notation
Factory default: (blank)
This parameter can only be set using a phone's config file.

speed_labelx - Optional - Configures the speed-dial key label. The x variable is from label 2 to label 6. There are five possible labels that can be configured on the Cisco IP 7960G but only one on the Cisco IP 7940G. The x variable is a string of up to 15 characters.
Note This parameter cannot be set in the configuration file.

speed_linex - Optional - Configures the speed-dial keys so that the user can set up one-touch dialing. There are five possible numbers that can be configured on the Cisco IP 7960G but only one on the Cisco IP 7940G. The x variable is a string of up to 128 bytes.
Note This parameter cannot be set in the configuration file.

start_media_port - Optional - Start RTP range for media.
Range is from 16384 to 32766.
Factory default: 16384
This setting can only be made using a phone's config file.

stutter_msg_waiting - Optional - Enables a stutter dial tone when there is a message waiting.
Valid values:
0 (off)
1 (on)
Factory default: 0

sync - Optional - Value against which to compare the value in the syncinfo.xml file before a remote reboot is performed.
Valid values: up to 32 characters
Factory default: ??
This setting can only be made using a phone's config file.

telnet_level - Optional - Enables Telnet for the phone.
Valid values:
0 - Disabled
1 - Enabled, and no privileged commands can be executed.
2 - Enabled, and privileged commands can be executed.
Factory default: is 0
This setting can only be made using a phone's config file.

tftp_cfg_dir - Path to the TFTP subdirectory in which phone-specific configuration files are stored.
Note This parameter is only required if the phone-specific files are in a subdirectory and not in the root directory.
Factory default: (blank)
This setting can only be made using a phone's config file.

time_format_24hr - Optional - Whether a 12-hour or 24-hour time format is displayed by default on the user interface.
Valid values:
0 - 12-hour format is displayed by default but can be changed to a 24-hour format by the user.
1 - 24-hour format is displayed by default but can be changed to a 12-hour format by the user.
2 - 12-hour format is displayed and cannot be changed to a 24-hour format by the user.
3 - 24-hour format is displayed and cannot be changed to a 12-hour format by the user.
Factory default: 1

time_zone - Optional - Time zone in which the phone is located.
Valid values are the time-zone abbreviations shown in Table 3-5. Abbreviations are case sensitive and must be in all capital letters.
Factory default: PST

timer_invite_expires - Optional - Amount of time, in seconds, after which a SIP INVITE expires. This value is used in the Expire header field.
Valid values: any positive number. However, Cisco recommends 180.
Factory default: is 180
This setting can only be made using a phone's config file.

timer_register_delta - Configures the time interval at which reregistration will occur. This is a numeric field in which the time interval is measured in seconds.
Valid values: range from 32767 to 0
Factory default: 5 (phone will attempt to reregister 5 seconds before its registration period expires).
This setting can only be made using a phone's config file.

timer_register_expires - Optional - Amount of time, in seconds, after which a REGISTRATION request expires. This value is inserted into the Expire header field.
Valid values: any positive number. However, Cisco recommends 3600.
Factory default: 3600
This setting can only be made using a phone's config file.

timer_t1 - Optional - Lowest value, in milliseconds, of the retransmission timer for SIP messages.
Valid values: any positive integer
Factory default: 500
This setting can only be made using a phone's config file.

timer_t2 - Optional - Highest value, in milliseconds, of the retransmission timer for SIP messages.
Valid values: any positive integer greater than timer_t1
Factory default: 4000
This setting can only be made using a phone's config file.

transfer_onhook_enabled - Optional - If enabled, a user can transfer a call to a second user by hanging up the phone once the second user picks up the line. If disabled, a user must, before hanging up, press the Transfer button again to complete the transfer.
Valid values:
0 - Disabled
1 - Enabled
Factory default: 0
This setting can only be made using a phone's config file.

user_info - Optional - Configures the "user=" parameter in the REGISTER message.
Valid values:
none - No value is inserted.
phone - The value user=phone is inserted in the To, From, and Contact Headers for REGISTER.
ip - The value user=ip is inserted in the To, From, and Contact Headers for REGISTER.
Factory default: none
This setting can only be made using a phone's config file.

version_stamp - The version of the configuration file, used by the phone to determine when a new confguration file appears on the TFTP server.
Valid value: a 64-byte string
Factory default: null
This setting can only be made using a phone's config file.

voip_control_port - Optional - UDP port used for SIP messages. All SIP REQUESTS use voip_control_port as the UDP source port when nat_enable = 1.
Valid values: 1025 - 65535
Factory default is 5060
This setting can only be made using a phone's config file.