Social Network Services

Description

Social Network Services (SNS) within the 3GPP context are not a single protocol or interface, but a broad category of over-the-top (OTT) applications and services that leverage mobile network capabilities. 3GPP standards address SNS by defining requirements, architectures, and enablers that allow these services to integrate efficiently with mobile networks. This involves aspects like service discovery, quality of service (QoS) differentiation, policy control, charging, and secure exposure of network APIs. Architecturally, SNS applications typically reside in the Internet or service provider domains, but they interact with the 3GPP network through defined interfaces like the SCEF (Service Capability Exposure Function) in the 4G/5G core. The network provides enablers such as user authentication (via the HSS), location services (via GMLC), and notification services.

How SNS works from a 3GPP network perspective involves several layers. At the service layer, SNS providers offer applications that users access via UE (User Equipment). The 3GPP network's role is to provide reliable, secure, and quality-assured connectivity. For enhanced integration, 3GPP defines mechanisms like Access Point Name (APN) configurations optimized for SNS traffic, which might route data through specific gateways (PGW/UPF) with tailored policies. The Policy and Charging Control (PCC) architecture can apply specific QoS policies for SNS traffic, ensuring a better user experience for real-time features like video calls. Furthermore, network APIs exposed via SCEF/NEF (Network Exposure Function) allow SNS providers to request network information (e.g., user status, location with consent) or trigger network actions (e.g., sending SMS notifications), enabling richer, context-aware services.

Key components involved in supporting SNS include the User Equipment (UE), the Radio Access Network (RAN), the Core Network (with PCF, SMF, UPF), and the external SNS application server. The interaction is governed by 3GPP specifications that ensure security, privacy, and interoperability. For example, TS 22.801 outlines service requirements, TS 26.253 may cover media aspects for social TV, and TS 48.016 could relate to interworking with legacy GSM systems for SNS access. The network manages the data bearers, applies charging data records (CDRs) for SNS usage, and ensures that the massive, often bursty, data traffic from SNS does not negatively impact other network services through intelligent traffic management.

Purpose & Motivation

The formal consideration of Social Network Services (SNS) in 3GPP standards was motivated by the explosive growth of platforms like Facebook, Twitter, and later Instagram, and their profound impact on mobile network usage patterns. Prior to this, mobile networks were primarily designed for voice, SMS, and basic web browsing. The rise of SNS created new challenges: massive increases in data traffic, demand for always-on connectivity, and the need for low-latency interactions for features like messaging and live video. 3GPP began addressing SNS to ensure mobile networks could efficiently support these services, which were becoming a primary driver of mobile data consumption and a key factor in user choice of operator.

Historically, SNS started as OTT services, operating independently of operator networks. This led to problems like network congestion, inability to guarantee quality for real-time social features, and missed opportunities for operators to monetize or integrate with these services. 3GPP's work on SNS, starting notably in Release 8, aimed to create a framework for cooperation. It sought to solve the problem of the network being a 'dumb pipe' by defining standardized ways for operators to expose network capabilities (like quality on demand, authentication, billing) to SNS providers. This would enable new business models, such as sponsored data or enhanced QoS for specific SNS applications, benefiting both operators and service providers.

The creation of requirements and architectural enablers for SNS was driven by the need to maintain a high quality of experience (QoE) for users, manage network resources efficiently, and foster an ecosystem where innovative services could thrive on mobile networks. It represented a shift in 3GPP's scope from defining only the network plumbing to also considering the popular applications that run on top of it, ensuring the network architecture evolved to be application-aware and service-friendly.

Key Features

• Category of OTT applications leveraging mobile connectivity
• Drives requirements for high data throughput and low latency in networks
• Integrated with 3GPP PCC for QoS differentiation and charging
• Utilizes network exposure functions (SCEF/NEF) for capability access
• Impacts traffic management and policy control architectures
• Subject to specifications covering service requirements and media handling

Evolution Across Releases

Defining Specifications