## 3 Architectures in the 5G and LPWAN-IoT and Smart Cities
### LPWAN Architecture
It supports devices with a wide range of message length sizes, including support for device mobility to some extent [11]. It has support for high capacity and scalability;  
* Narrowband IoT  
Like the LTE-M, the Narrowband IoT (NB-IoT) is also in the 3 GPP Release 13 LPWAN technology. However, it operates with lower complexity and at a lower data rate when compared to LTE-M. NB-IoT also operates in the licensed LTE band but with the flexibility for deployment in the global system for mobile communications (GSM) licensed frequency bands (700 MHz, 800 MHz, and 900 MHz). It uses two-way communication in which the orthogonal frequency division multiple access (OFDMA) is used for downlink, and single carrier frequency division multiple access (SC-FDMA) is used for uplink [53]. It connects 50,000 devices per base station and uses a channel bandwidth of 180 kHz to establish communication. It has a 200-kbps data rate for downlink and 20 kbps for uplink, with a battery life of up to 10 years. However, an enhancement to the NB-IoT is the 3 GPP Release 14 enhanced NB-IoT, it is called LTE Cat NB2, which enhances the NB-IoT protocol in several ways such as high positioning accuracy; introduces NB-IoT Multicast; enhances device mobility; high data rate; increases peak data rates; introduces NB-IoT Multi-carrier operation; additional lower device power class; lower latency and new NB-IoT frequency bands allocation [54]. Further enhancement of the LTE-M and NB2- IoT which were previously on 4G/LTE-enabled platforms has now been finalized as a 5G-based IoT (eMTC and NB2-IoT-enhanced) respectively, this was announced in the latest release of 3 GPP Rel-17 [6]. This will support IoT devices at 5G narrowband features with an appreciable data rate than the previous LTE-M and NB-IoT. The latest enhancement in the 5G user equipment (UE) is the New Radio (NR) Light-IoT or 5G reduced capability (RedCap) IoT device which will operate on 5G NR and is part of release 17 of the 3 GPP [6]. Table 2 shows LPWAN technologies comparisons, while Table 3 shows 3 GPP release numbers and their details. * EC-GSM-IoT  
Enhanced coverage-global system for mobile Internet of Things (EC-GSM-IoT), introduced by 3 GPP in its release 13 for LPWAN cellular IoT (CIoT), with support for similar coverage and longer battery life as NB-IoT [55]. The design is based on enhanced General Packet Radio Service (eGPRS) for the IoT, and existing GSM Networks can be upgraded using a software application to ensure wider coverage and accelerated time of deployment. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**LPWAN** & **Frequency** & **Latency** & **Throughput** & **Range (km)** & **Channel** \\
**Non-3 GPP/3 GPP** & **Spectrum** & **Latency** & **Throughput** & **Range (km)** & **Bandwidth** \\ \hline LoRaWAN & \textless{}1 GHz & Low & \textless{}40 kbps & 30 & \textless{}500 kHz \\ Sigfox & \textless{}1 GHz & Low & \textless{}150 bps & 50 & 100 kHz \\ Dash & \textless{}1 GHz & Low & \textless{}200 kbps & 10 & \textless{}200 kHz \\ RPMA & 2.4 GHz & Low & \textless{}19,000 bps & 20 & 80 MHz \\ Weightless-W & TVWS (\textless{}900 MHz) & Low & \textless{}10 Mbps & 20 & 5 MHz \\ Weightless-N & \textless{}1 Ghz & Low & \textless{}100 bps & 5 & 200 Hz \\ Weightless-P & 880–915 MHz & Low & \textless{}100 kbps & 4 & \textless{}100 kHz \\ LTE-M & 455–2600 MHz & Very low & \textless{}1 Mpsps & 5 & 1.44–5 MHz \\
5G eMTC & 455–3500 MHz & Very low & \textless{}2 Mbps & 7 & 1.44–5 MHz \\ NB-IoT & 455–2100 MHz & Very low & \textless{}0.54 Mbps & 7 & 180–200 kHz \\
5G NB2-IoT & 455–3500 MHz & Very low & \textless{}0.78 Mbps & 10 & \textless{}500 kHz \\ LTE-Cat1 & 455–3500 MHz & Very low & \textless{}10 Mbps & 5 & 20 MHz \\ EC-GSM-IoT & 395–1060 MHz & Very low & \textless{}0.5 Mbps & 8 & \textless{}500 kHz \\ IEEE 802.11 ah & \textless{}1 Ghz & Very low & \textless{}30 Mbps & 2 & \textless{}16 MHz \\ \hline \hline \end{tabular}
\end{table} 
Table 2: LPWAN Technologies Comparisons.