E-Lins Technology provides a great description on what is a 4G Router?

1. What’s a 4G Router?
4G Wireless Router is a kind of router with a 4G network module for 4G network.
4G/LTE Router is a wireless gateway for your wireless terminals to access the internet.
The 4G router connects to the mobile network with the latest 4G technology and can
distribute it in different ways, for example via separate LAN ports or WiFi. Depending
on your type of 4G router, you can share the connection with multiple users. The
feature of the 4G router is that it has one or two SIM card slots. Some may also have
Ethernet port or not. Usually, the 4G wireless router would provide internet
connection through WiFi. The LTE WiFi router usually has one SIM card slot, after SIM
card plugin, it could be the access point for multiple WiFi-enabled devices, such as PC,
laptop, tablets, smartphones etc.
The 4G Routers with Ethernet ports and SIM card slot are usually 4G Stationary
router for home or office use in a small group of people. However, some new 4G
pocket WiFi routers are configured with Ethernet port for WAN or LAN or together.
These 4G portable WiFi routers with Ethernet port make the gadget to be taken for
outdoor activities. it's also called 4G WiFi Router. Usually, the 4G Router with
Ethernet ports are for LAN, and there are 4 LAN ports, sometimes, there may be 1 or
2 ports. The most important is that it must have two external antenna port to
support MIMO data transmission. For the LTE router without any LAN ports, we call
them 4G LTE Mobile Hotspot, 4G LTE MiFi or 4G Mobile WiFi. Some people call them
portable 4G router and they can support at least 5 users to access the internet with
peak speed up to 100Mbps. E-Lins Technology offers all kinds of 4G Router per
customers' preference and their network status. They are all unlocked to make the
4G Routers could roam in different LTE networks.
Characteristic display
1. Support APN, VPDN public network and private network access
2. Supports TDD-LTE and FDD-LTE networks, and is automatically compatible with 3G
networks downwards.
3. Supports backup switching between PPPOE, DHCP, static IP and 4G network
Intelligent filtering: Under the 3G/4G network standard, one IP or IP segment under
the router can be prohibited from accessing the external network; when switching to
the wired network, it can be normally connected.
4. Support PING detection restart and SMS remote restart function
5. Support virtual routing redundancy protocol VRRP
6. Support multiple VPN encryption protocols

2. 7. Independent software and hardware watchdog design to ensure reliable system
operation
It has protection measures such as low pressure, overcurrent, overvoltage and
anti-reverse connection.
DC5-40V wide voltage input (enhanced version can support DC60V input)
8. Support local and remote firmware upgrades
9. Support parameter export and backup to facilitate large-scale configuration of
devices
10. Provide system local log and remote log sending to realize real-time network
monitoring
11. Supports QoS, which can perform uplink/downlink QoS bandwidth intelligent
management for ports and IP network segments.
12. The device has a standard RS232/485 interface and can be used as a DTU
function.
13. Support static routing, policy routing, and dynamic routing
14. LED status monitoring. Display power, system, 3G/4G network connection status
and signal strength (level 3 signal indicator), VPN connection status
Specifications
CPU
RAM: 512Mbit
FLASH: 128Mbit
Power
Input voltage DC 5-40V
Power consumption:
Free time: 180mA@12VDC
Work: 410mA@12VDC
Working environment
Storage temperature: -35 ° C ~ 85 ° C
Operating temperature: -35 ° C ~ 75 ° C
Relative humidity: <95%
Interface
1 WAN 10/100Mb RJ45
4 LAN 10/100Mb RJ45
1 standard DB9 serial port, RS232/RS485/TTL
1 2PIN terminal for serial port and power input
1 SIM card slot
1 4G antenna interface (50Ω female)
2 WIFI antenna interface (50Ω female)
1 RESET button
1 WPS button
Metal enclosure protection rating: IP30

3. Supporting agreement
TCP, UDP, DHCP
DNS, DDNS
Port mapping, port triggering
Way of working
Always online
Go online as needed
Scheduled online
VPN function
IPSec client
PPTP client
L2TP client and server
GRE client
DTU function
Support TCP & UDP server, client mode
Serial port baud rate: 300~115200bps
Send serial data to 4-way server at the same time
Automatic restart (to prevent false connections)
ICMP link detection restart
Scheduled restart
SMS restart
Management method
Web
Telnet
SNMP
TRO69 network management
Firewall
IP, MAC address filtering
URL filtering
WIFI
WIFI 802.11n 300Mbps
Allow 50 users to access simultaneously
Multiple encryption methods
Coverage: Straight line distance of 100 meters (without occlusion)
Coverage band
TDD-LTE: 2600MHz (B38), 1900MHz (B39), 2300MHz (B40),
FDD-LTE:2600MHz (B7), 2100MHz (B1)1800MHz (B3), 900MHz (B8)800MHz (B20),
Bandwidth (downstream, uplink)
FDD-LTE: 150Mbps/50Mbps
TDD-LTE: 112Mbps/10Mbps
TD-SCDMA: 2.8Mbps/2.2Mbps

4. DC-HSPA+: 42Mbps/5.76Mbps
GPRS: 85.6kbps / 42.8kbps
Accessories (can be customized)
1 network cable
1 power adapter (AC110~240V-DC12V)
1 4G antenna
2 WIFI antenna (optional)
Industrial 4G LTE wireless routers are designed for rapid networking of IoT
terminals. The router adopts Qualcomm's industrial CPU, built-in industrial grade 4G
LTE module, and integrates Ethernet port WAN, LAN and industrial RS232, RS485
serial port and 300Mbps Wi-Fi service. With ICMP detection and independent
software and hardware watchdog design, automatic disconnection of dropped calls
ensures that the device is online for 7*24 hours. Industrial grade standard design,
through electromagnetic compatibility EMC test and vibration test, stable operation
in the harsh environment of -35~+70 °C. DC7-36V wide voltage input, support a
variety of VPN encryption protocols (PPTP, L2TP, IPSec, GRE), and Cisco, Huawei, and
other servers for easy docking, standard RS232/RS485 interface can be used as DTU
for serial data transmission. Since the industrial 4G router was put on the market, its
stable and reliable performance has won the trust of a large number of customers. At
present, this series of routers have been widely used in automotive video
surveillance, self-service terminal rapid networking, water monitoring, Municipal
engineering，Oil monitoring，Agricultural applications，Wireless WIFI applications
remote meter reading, environmental monitoring and other industrial products The
field of networking. Industrial routers are about to usher in the 5G era, let us just
around the corner！