Table 1 Standalone Vs. Assisted GPS

Standalone GPS	Assisted GPS (A-GPS)
Data network required: No	Data network required: Yes
GPS antenna required: Yes	GPS antenna required: Yes
Minimal visible satellite: 4	Minimal visible satellite: 2

Secure User Plane Location (SUPL) Protocol

■The SUPL Protocol is an IP based protocol for Assisted GPS to receive information about GPS satellites quickly via IP.

■The modem uses a SUPL server to download almanac and/or ephemeris data and obtain cellular tower reference location to speed up Time To First Fix (TTFF).

■There are 2 type of SUPL servers; Google’s SUPL server or Carrier based SUPL server. The Cisco A-GPS feature uses the one from Google.

■Google’s SUPL server can be used on an encrypted or unencrypted TCP port. The way Cisco implemented the A-GPS feature uses an encrypted TCP port.

■Using the OEM PRI update for A-GPS will enable standard type SUPL certificate (GeoTrust Global CA) on the modem and configure the modem for correct SUPL settings to reach Google SUPL server.

Assisted GPS Requirements on Cisco Routers

Your particular router/modem needs to meet the following requirements:

■Modem needs to have OEM PRI version that supports SUPL/A-GPS.

–Later factory released routers/modems may already come with supported SUPL OEM PRI version. See MC73XX Modems and 74XX Modems for OEM PRI version that supports SUPL/A-GPS for each modem model.

–SUPL OEM PRI files can be downloaded at: https://software.cisco.com/download/navigator.html?mdfid=286288566&flowid=76022

–For MC7354MNA and MC7304 modems, SUPL OEM PRI upgrade will need to be done in 2 firmware upgrade processes.

–There is no SUPL OEM PRI for MC7330 modem since it is EOS/EOL.

■On the ISR4K router, the appxk9 license is needed for A-GPS feature to be available for configuration.

The following tables list the OEM PRI versions that support SUPL/A-GPS.

 

 

Table 3 74XX Modems

Modem Upgrades

For the 74xx series modems, SUPL OEM PRI upgrade uses a.nvu file. This can be accomplished with the current firmware on the modem.

The following example shows EM7455 modem:

For MC73xx modems, SUPL OEM PRI upgrade uses a.spk file. This type of file changes the following:

■Firmware

■Carrier

■OEM PRI

For the MC7350 and MC7354 modems, the SUPL OEM PRI upgrade is a one step process. Choose the.spk file for the modem currently in the router.

For the MC7354MNA and MC7304 modems, the SUPL OEM PRI upgrade requires a 2 step process, (depending on which carrier you want to use).

1. SUPL OEM PRI firmware upgrade with.spk file. (This would have the modem changed to default carrier.)

2. Firmware upgrade the modem to desire carrier.

Note : For the MC7354MNA the default carrier is Verizon. For the MC7304 the default carrier is Telstra.

MC7354MNA Example

To upgrade the OEM PRI to a version that supports A-GPS and with the desired carrier (AT&T), use the following example:

The CLI to change the OEM PRI (same as FW upgrade) is microcode reload cellular 0 <slot> modem-provision flash: <oem_pri_folder>

Example before SUPL OEM PRI upgrade:

 

Example after SUPL OEM PRI upgrade:

- Firmware file: MC7354MNA_1102407_05.05.58.01_00_VZW_005.003_000.spk

- OEM PRI version got changed (05.03) and carrier got changed to default carrier (Verizon).

 

Example after switching to desire carrier (AT&T):

- Firmware file: MC7354MNA_9999999_9902196_05.05.58.00_00_ATT_005.026_000.spk

 

Assisted GPS Configuration

To enable or disable Assisted GPS, use the l te gps mode ms-based command.

For example:

Note : NMEA configuration is the same as Standalone GPS feature.

Assisted GPS Command Outputs

Assisted GPS Output for Reference/Cell Tower Location

Use the show cellular 0 gps command:

Assisted GPS LEDs

Different routers have individual ways of indicating assisted GPS via their LEDs.

Here are some examples:

C800 Routers

■Off = GPS feature is disabled
= GPS feature is enabled without GPS mode and NMEA configuration

■Amber (Blinking) = GPS is acquiring

■Amber (Solid) = GPS coordinates are acquired

IR829 Routers

■Off = GPS feature is disabled
= GPS feature is enabled without GPS mode and NMEA configuration

■Green (Fast Blink) = GPS is acquiring

■Green (Solid) = GPS coordinates are acquired

4G LTE EHWIC on C1900, C2900, or C3900 Routers

■Off = GPS feature is disabled
= GPS feature is enabled without GPS mode and NMEA configuration
= GPS is acquiring

■Green (Solid) = GPS coordinates are acquired

Note : LED color/behavior is reflective of which GPS mode is configured. This applies even when the modem falls back to GPS Standalone mode.