What is private LTE? If we have WiFi, why do we need it?

With LTE, mobile phones get a much higher data speed on mobile devices. Usually, mobile operators own the LTE network. A subscriber buys the SIM card and starts using data services. The service is not restricted to an organization or company.

But what if an organization wants a network for high-speed data, but usage is limited to a few SIM cards or in an Area only? The answer is private LTE.

A company buys the spectrum( or share) from the LTE band in private LTE after setting up the core network and access network. When a mobile device comes under coverage, it attaches to the private LTE network and starts using services from the company. If the company allows else, it moves to the regular mobile network if there is any.

Why do we need Private LTE?

Mobile operators have an LTE network in all places, then why a company needs its own similar private network? This is because of the need for dedicated services, or it’s good to pay a one-time setup fee and not each month hefty data charges.

Very useful for a company when they have millions of IoT devices. The mobile operator will charge for each SIM card each month. Once there is a private LTE, only a one-time setup cost will be there.

Why do we need Private LTE if we have WiFi?

The LTE is a data-only network, and the VoLTE further enables voice calls over the data network. But mostly, private LTE is about data connectivity. So why do we need to use new technology? As we have WiFi for data? 

The first answer is coverage and the reachability of the network. The LTE access network can cover a vast area as compared to WiFi. If we try to get the same range, the cost of the WiFi setup will be huge.

With Private LTE, the data and communication are more secure than WiFi.

How to set up a Private LTE?

As the name implies private, so to set up a private LTE, the organization should have all the components for the LTE network. Here we will describe all the network components for private LTE. Some of the components may be owned by mobile network operators too.

eNodeB: This mobile tower will connect to the device over the radio interface while, on another side, it will connect to the fixed network over the wire.

MME: In LTE, MME is the node on the roaming site. It does the signaling for setting up a data connection with the UE. It also does handover and hand-in if the subscriber moves from Private to public LTE and vice versa.

SGW:  This is the serving gateway. It creates a session with the PGW in the home network for data. On-device attach, MME does signaling with SGW for the data session. If there is control plane optimization for IoT devices, then eNodeB sends the data via MME. Else eNodeB sends data directly to the SGW over UDP using the GTP-U protocol.

HSS in LTE: HSS is the node in the LTE network having a subscription for a SIM card. It is also co-located with the AUC. When the subscriber attaches, MME does the signaling with the HSS for authentication and does the update location for downloading the subscriber profile.

PGW: A gateway between SGW and external PDN network for internet access. SGW sends and receives data from the PGW over the GTP-U protocol.

Other than eNodeB, all other components may be located with a mobile network operator. The mobile operator may reserve a dedicated capacity for a private LTE for each element.