CELLULAR

The cellular interface provides connection to mobile broadband networks using standards defined by 3GPP (3rd Generation Partnership Project).

3GPP has defined a wide range of standards (such as GSM, GPRS, UMTS, HSDPA, LTE, 5G) with different properties: range of coverage, minimum achievable latency, downlink/uplink max throughput, etc.

The cellular interface is implemented using “modules” from different vendors. Depending on the “module” installed in each device, the cellular interface will have different capabilities.

Operational commands interfaces cellular show capabilities can be used to list the cellular interfaces that are configurable on the system, as well as any relevant information on the “modules” installed.

Example:

admin@osdx$ interfaces cellular show capabilities
cell0
   Module Manufacturer: Quectel
   Module Model: EC25E
   Module Firmware: EC25EFAR06A01M4G_TEL
   Hardware Revision: 10000
   IMEI: 866308062070222
   Radio Interfaces: gsm, umts, lte
   Data Service Capability: non-simultaneous-cs-ps
   Maximum TX/RX rate supported: 50000/100000 Kbps
   Bands: gsm-dcs-1800, gsm-900-extended, gsm-900-primary, wcdma-2100, wcdma-850-us, wcdma-900
   LTE bands: 1, 3, 5, 7, 8, 20, 38, 40, 41

Profile 

Once the cellular interfaces available in the system are known, they can be configured. To do this, the first thing to do is define a cellular profile that will be later assigned to the cellular interface being configured.

To create a cellular profile, use the cellular profile <id> command to give it a name and adjust the different parameters:

apn: configures the APN (Access Point Name) used to establish the connection to the mobile broadband network (mandatory).
username: configures the username to be used in network authentication.
password: configures the password to be used in network authentication.
auth: configures the protocol to be used in network authentication. One of the following values (default, both) can be selected.
- chap: use the Challenge Handshake Authentication Protocol.
- pap: use the Password Authentication Protocol.
- both: use CHAP and PAP.

Once the cellular profile has been created, the cellular interface can be configured. To do this, use the interfaces cellular <txt> command, indicating the name of the interface you want to configure (eg: cell0). By means of the profile field, you must also select the cellular profile used by this interface.

Personal Identification Number (PIN)

In order to establish a connection to the mobile broadband network, a SIM card must be inserted in the corresponding slot.

Sometimes, the SIM card is locked by a PIN code. In these cases, configure the SIM card’s PIN code using the pin field.

Once the cellular interface is configured, the status of the SIM card can be checked via the interfaces cellular <value> show network-status operational command.

Example:

admin@osdx$ interfaces cellular cell0 show network-status
SIM status = OK
Registration state = registered
Public Land Mobile Network code = 21407
Public Land Mobile Network name = Movistar
Network technology currently in use = lte
Current Service Domain registered = cs-ps (capable cs-ps)
Current Roaming status = off
3GPP Cell ID = 28195870
Radio Band = eutran-3
Channel = 1301
LTE Tracking Area Code (TAC) = 11091
RX level (dBm) = -69
Coverage level = 4 (**** )

SIM card errors can sometimes cause network connectivity issues. This can be checked using the previous operational command. Instead of displaying “SIM status = OK”, it will display “SIM Status = LOCKED” and detail the error in brackets.

A list of the most common errors is included below:

SIM not inserted: the system does not find any inserted SIM card.
PIN not configured: the inserted SIM card is locked by a PIN code that has not been added to the configuration.
Incorrect password: the inserted SIM card is locked by a PIN code, and the code added to the configuration is incorrect.
SIM PUK required: the inserted SIM card is locked by a PUK code.

The “SIM PUK required” error usually occurs when the number of attempts to enter a correct PIN code on the SIM card is exceeded. As a result, the SIM is locked by a PUK code. To solve this, the interfaces cellular <value> open-at-terminal operational command must be launched and AT+CPIN=”12345678”,”1234” must be written in the AT terminal (with 12345678 as the PUK code and 1234 as the new PIN code that you want to assign to the SIM card). If the AT terminal then displays OK, it means that the SIM card has been successfully unlocked.

Example:

admin@osdx$ interfaces cellular cell0 open-at-terminal
AT+CPIN="12345678","1234"

OK

Network Mode 

Additionally, the type of technology the cellular interface used to connect to the mobile broadband network can be selected. This can be done via the interfaces cellular <txt> network mode <txt> command, selecting one of the following values (default, automatic).

automatic: using the best technology available.
cdma: only using CDMA.
gprs: only using GPRS.
hrpd: only using CDMA HRPD.
hybrid: using CDMA or CDMA HRPD.
lte: only using LTE.
wcdma: only using UMTS/HSDPA.

Depending on the cellular “module” installed in the device, some modes from the list above will not be supported. If you try to select a mode that is not supported by a “module”, an error message will be displayed.

Example:

admin@osdx# set interfaces cellular cell0 network mode cdma
  "cdma" is not a network mode supported by cell0 (Quectel EC25E). Supported modes are: gprs, lte, wcdma
  Value validation failed
  CLI Error: Command error

The technology currently used by the cellular interface can be checked via the interfaces cellular <value> show network-status operational command.

Example:

admin@osdx$ interfaces cellular cell0 show network-status
SIM status = OK
Registration state = registered
Public Land Mobile Network code = 21407
Public Land Mobile Network name = Movistar
Network technology currently in use = umts
Current Service Domain registered = cs-ps (capable cs-ps)
Current Roaming status = off
3GPP Location Area Code = 1109
3GPP Cell ID = 40106379
Radio Band = wcdma-900
Channel = 3034
WCDMA Primary Scrambling Code (PSC) = 443
WCDMA High-Speed Call Status = hsdpa-hsupa-unsupported
WCDMA High-Speed Service Indication = hsdpa-hsupa-unsupported
EcIo (dB) = -7.5
RX level (dBm) = -82
Coverage level = 3 (***  )

Multi-APN 

The Profile section has shown how to assign a cellular profile (with a specific APN defined) to a cellular interface in order to create a single PDP (Packet Data Protocol) context. By doing this, only one PDN (Packet Data Network) data call can be configured over the same cellular interface.

However, some “modules” (i.e.: Quectel modules) allow for multiple virtual interfaces to be created on the same cellular interface, meaning users can configure multiple PDN data calls.

To create a Multi-APN configuration in OSDx, the interfaces cellular <txt> profile <id> command should not be used to configure the cellular interface. Instead, use the interfaces cellular <txt> pdp <u32> profile <id> command, indicating the virtual interface to be configured (from 1 to 4) and the cellular profile to be assigned.

Here, you can find an example related to Multi-APN.

Examples 

Single-APN 

Imagine that you want to configure the cell0 cellular interface, for which a SIM card with PIN code 1234 is inserted. Additionally, you want to connect this interface to the mobile broadband network through the oper_apn.com APN only using the UMTS/HSDPA technology.

In OSDx, this can be achieved by entering the following commands:

set cellular profile CELPROFILE apn oper_apn.com
set interfaces cellular cell0 address dhcp
set interfaces cellular cell0 network mode wcdma
set interfaces cellular cell0 pin 1234
set interfaces cellular cell0 profile CELPROFILE

Multi-APN 

Imagine that you want to configure two PDN data calls over the cell0 cellular interface. Additionally, you want to connect each of these virtual interfaces to the mobile broadband network as follows:

Using the APN oper_apn1.com for virtual interface 1.
And, using the APN oper_apn2.com for virtual interface 2.

In OSDx, this can be achieved by entering the following commands:

set cellular profile CELPROFILE1 apn oper_apn1.com
set cellular profile CELPROFILE2 apn oper_apn2.com
set interfaces cellular cell0 pdp 1 address dhcp
set interfaces cellular cell0 pdp 1 profile CELPROFILE1
set interfaces cellular cell0 pdp 2 address dhcp
set interfaces cellular cell0 pdp 2 profile CELPROFILE2
set interfaces cellular cell0 pin 1234

Here, you can find more interfaces cellular examples.

Monitoring 

In OSDx, there are several operational commands related to interfaces cellular that can display valuable information or allow some action to be executed on these interfaces.

Up until now, some of these operational commands have been detailed:

The interfaces cellular show capabilities command displays a list of configurable cellular interfaces, as well as relevant information on the “modules” installed in the device.
The interfaces cellular <value> show network-status command shows information about the state of the radio link (SIM status, registration state, network technology currently in use, …).
The interfaces cellular <value> open-at-terminal command allows a terminal in which to execute AT commands to be opened (for example, to unlock the SIM card by inserting the PUK code).

But these are not the only operational commands related to interfaces cellular that are available.

The interfaces cellular <value> show device-info command displays information on the “module” installed in the device.

Example:

admin@osdx$ interfaces cellular cell0 show device-info
Module Manufacturer          = Quectel
Module Model                 = EC25E
Module Firmware              = EC25EFAR06A01M4G_TEL
Hardware Revision            = 10000
IMEI                         = 866308062070222
IMSI                         = 214075541654235
ICCID                        = 8934075700105849704F
Radio Interfaces             = gsm, umts, lte
Data Service Capability      = non-simultaneous-cs-ps
Maximum TX/RX rate supported = 50000/100000 Kbps
Temperature                  = 44

The interfaces cellular <value> show supported-bands command displays the bands supported by the “module” installed on the device.

Example:

admin@osdx$ interfaces cellular cell0 show supported-bands
Bands     = gsm-dcs-1800, gsm-900-extended, gsm-900-primary, wcdma-2100, wcdma-850-us, wcdma-900
LTE bands = 1, 3, 5, 7, 8, 20, 38, 40, 41

The interfaces cellular <value> show preferred-bands command shows the preferred bands to be used by the cellular interface.

Example:

admin@osdx$ interfaces cellular cell0 show preferred-bands
Bands preference     = gsm-dcs-1800, gsm-900-extended, gsm-900-primary, wcdma-2100, wcdma-850-us, wcdma-900
LTE bands preference = 1, 3, 5, 7, 8, 20, 38, 40, 41

The interfaces cellular <value> show cell-info command displays information about the serving cell and neighboring cells.

Example:

admin@osdx$ interfaces cellular cell0 show cell-info
LTE intrafrequency info:
   UE in idle mode                   = no
   PLMN ID coded                     = 21407
   Tracking Area Code                = 11091
   Global cell ID                    = 28195872
   E-UTRA absolute RF channel number = 2850
   LTE serving cell ID               = 290
   Cell #0
      Physical cell ID        = 290
      Current RSRQ (dB)       = -11.300000
      Current RSRP (dBm)      = -109.300000
      Current RSSI (dBm)      = -76.200000
      Cell selection Rx Level = 0

LTE interfrequency info:
   UE in idle mode = no

LTE info - Neighboring GSM:
   UE in idle mode = no

LTE info - Neighboring WCDMA:
   UE in idle mode = no

The interfaces cellular <value> show signal-quality command displays information about the quality of the signal received by the module.

Example:

admin@osdx$ interfaces cellular cell0 show signal-quality
LTE:
   RSSI (dBm) = -78
   RSRP (dBm) = -109
   RSRQ (dB)  = -8
   SNR (dB)   = 12.000000
Rx Chain #0
   Radio tuned    = yes
   Rx Level (dBm) = -80.700000
   ECIO (dB)      = 8.400000
   RSRP (dBm)     = 109.100000
   Phase (deg)    = 0.000000
Rx Chain #1
   Radio tuned    = yes
   Rx Level (dBm) = -82.200000
   ECIO (dB)      = 8.200000
   RSRP (dBm)     = 110.400000
   Phase (deg)    = 0.000000

The interfaces cellular <value> show network-data-connection command displays information about the network data connection.

Example:

admin@osdx$ interfaces cellular cell0 show network-data-connection
Connection status          = connected
Traffic channel status     = active
Max. TX channel rate (bps) = 50000000
Max. RX channel rate (bps) = 150000000
IPv4 address               = 37.13.233.100
IPv4 mask                  = 255.255.255.248
IPv4 gateway               = 37.13.233.101
IPv4 primary DNS           = 80.58.61.250
IPv4 secondary DNS         = 80.58.61.254

Finally, the interfaces cellular <value> reconnect command allows the user to force the cellular interface to reconnect to the mobile broadband network.

CELLULAR

Profile 

Personal Identification Number (PIN)

Network Mode 

Multi-APN 

Examples 

Single-APN 

Multi-APN 

Monitoring 

Command Summary 

Configuration commands 

Operational commands 