Cellular WLAN integration architecture | Cellular wifi network
This page describes Cellular and WLAN integration architecture and its benefits. It mentions elements of cellular wifi (i.e. WLAN) network architecture.
Introduction :
Cellular technologies (2G, 3G (UMTS), 4G, 5G NR) are evolving at much faster rate due to increased usage of
mobile phones across the globe. Moreover WiFi has become popular for sharing single broadband connection at homes and
offices by multiple users. WiFi follows WLAN (Wireless Local Area Network) specifications as defined in IEEE 802.11 series
of standards. 802.11 defines PHY and MAC layers.
Cellular technologies are mainly designed to provide wide coverage for high user density at different data rates. WiFi has been designed to provide very high data rates in limited space constrained environments mainly indoors and for certain distances in outdoors. WiFi supports low mobility where as cellular technologies support high mobility.
Both the technologies are complementary to each other. In order to leverage advantages of both, operators are looking to utilize integrated solution architecture involving both wifi and cellular. Moreover from data services point of view, they are interested in roaming between WLAN and cellular and vice versa to promote dual mode handsets.
There is no single architecture which fulfills all the requirements. Various architectures have been explored such as tightly coupled integration architecture (TCIA) , Loosely coupled integration architecture (LCIA) , combination of both TCIA and LCIA, Internet roaming global architecture etc. We will illustrate global architecture below used to integrate both Cellular and WLAN (i.e. WiFi) networks.

Figure-1 : UMTS architecture
Cellular WLAN integration architecture
One possibility is to connect WLAN at BSS/RNC which requires major changes to complex radio procedures as both the radio interfaces are completely different. The other possibility is to emulate WLAN as BSS/RNC by connecting through Gb interface at SGSN. This causes bottlenecks in the networks due to offload of cellular traffic to WLAN in large amount. The other alternative is to connect WLAN at GGSN which simplifies handover from cellular to WLAN but makes WLAN to cellular handover very slower. The most favourable solution is to interface WLAN to separate IP based network. This consecutively connects with cellular UMTS network via Gi interface as shown in the figure-1.

Figure-2 : Cellular WLAN (WiFi) integration architecture
The figure depicts global integration architecture of UMTS as cellular technology with WLAN. Here special server called certificate authority server (CA server) is deployed in order to check authenticity of fixed nodes and networks as per request. Here WLAN roaming is based on AAA broker with RADIUS proxy server. RADIUS is popular protocol which is used for integrating hotspot services into AAA based cellular networks.
Benefits of Cellular WiFi integration architecture
Following are the benefits of cellular WiFi integration architecture.
➨Cellular operators can offload data traffic to wifi hotspots during peak hours.
➨WiFi service providers can increase their subscriber database by establishing partnerships with cellular network operators.
➨End user will avail enhanced performance due to greater coverage, high data rates and low costs.
➨It helps in efficient utilization of radio spectrum.
➨The other cost effictive business applications are use of integrated voice services, seamless
wireless data services and common billing, secure communication, wireless multimedia and so on.
➨Flexible integration of new access networks at IP level.
➨Seamless handoff and roaming between wifi and cellular networks.
➨Mobile cellular device having WLAN capability will benefit at airports, cafes and bookstores to
gain access to free wifi internet services.
Conclusion : The proposed cellular wlan (i.e. wifi) integration architecture benefits all the stakeholders viz. cellular mobile operators, wifi data service providers and end users of both cellular and wifi networks.
Cellular and WiFi (i.e. WLAN) Technology RELATED LINKS
Cellular network vs Ad hoc network cellular frequencies Cellular communication tutorial WLAN tutorial What is wlan Cellular mifi vs wifi WLAN router providers advantages and disadvantages of 802.11ac (WiFi 5) advantages and disadvantages of 802.11ax (WiFi 6) BSS coloring in 11ax RU in 802.11ax MU-OFDMA in 802.11ax MU-MIMO in 802.11ax Difference between 802.11ac Wave1 and Wave2 Difference between 802.11n,11ac,11ad WLAN 802.11ac tutorial WLAN 802.11ax tutorial WLAN 802.11ac frame structure WLAN 802.11ac Physical Layer 802.11ac MAC Layer 802.11ax basics WLAN 11a,11b,11n,11ac frame structures
Other Architectures | GSM, GPRS, UMTS, Wimax, Zigbee, 5G, Satellite IoT, LoRa, SigFox, Femtocell
5G Cell Phone Architecture 5G Network Architecture WirelessHART WiMAX SDN Zigbee Smart Lighting Zigbee Smart Parking Satellite IoT GSM network architecture GPRS network architecture UMTS network architecture Femtocell LoRa Network Sigfox network MQTT protocol